diff --git a/docs/models/ipam/service.md b/docs/models/ipam/service.md
index fc6ab73d2..99128254b 100644
--- a/docs/models/ipam/service.md
+++ b/docs/models/ipam/service.md
@@ -23,13 +23,15 @@ The parent object to which the application service is assigned. This must be one
 
 A service or protocol name.
 
-### Protocol
+### Port Assignments
 
-The wire protocol on which the service runs. Choices include UDP, TCP, and SCTP.
+!!! note "Changed in NetBox v4.7"
 
-### Ports
+    Previously, a service defined a single `protocol` (UDP, TCP, or SCTP) shared by all of its `ports`. A service now defines a list of port assignments, where each assignment pairs an individual protocol with a port number. This allows a single service to combine multiple protocols — for example, a DNS service listening on both TCP/53 and UDP/53.
 
-One or more numeric ports to which the service is bound. Multiple ports can be expressed using commas and/or hyphens. For example, `80,8001-8003` specifies ports 80, 8001, 8002, and 8003.
+Each port assignment comprises a wire protocol (UDP, TCP, or SCTP) and a numeric port. In the UI, selecting multiple protocols alongside one or more ports creates an assignment for every protocol/port combination.
+
+The deprecated `protocol` and `ports` fields remain available in the REST and GraphQL APIs for backward compatibility. On read, `protocol` returns the single protocol shared by all assignments, or `null` when a service mixes protocols; `ports` returns the flattened list of port numbers. On write, supplying `protocol` and `ports` is translated into the equivalent port assignments (unless `port_assignments` is provided directly).
 
 ### IP Addresses
 
diff --git a/docs/models/ipam/servicetemplate.md b/docs/models/ipam/servicetemplate.md
index 9dd69b3c4..1b45e9ac0 100644
--- a/docs/models/ipam/servicetemplate.md
+++ b/docs/models/ipam/servicetemplate.md
@@ -12,10 +12,12 @@ Application service templates can be used to instantiate [application services](
 
 A service or protocol name.
 
-### Protocol
+### Port Assignments
 
-The wire protocol on which the service runs. Choices include UDP, TCP, and SCTP.
+!!! note "Changed in NetBox v4.7"
 
-### Ports
+    Previously, a service template defined a single `protocol` (UDP, TCP, or SCTP) shared by all of its `ports`. A template now defines a list of port assignments, where each assignment pairs an individual protocol with a port number. This allows a single template to combine multiple protocols — for example, both TCP/53 and UDP/53.
 
-One or more numeric ports to which the service is bound. Multiple ports can be expressed using commas and/or hyphens. For example, `80,8001-8003` specifies ports 80, 8001, 8002, and 8003.
+Each port assignment comprises a wire protocol (UDP, TCP, or SCTP) and a numeric port. In the UI, selecting multiple protocols alongside one or more ports creates an assignment for every protocol/port combination.
+
+The deprecated `protocol` and `ports` fields remain available in the REST and GraphQL APIs for backward compatibility, as described for [application services](./service.md).
diff --git a/netbox/ipam/api/serializers_/services.py b/netbox/ipam/api/serializers_/services.py
index 9d075dfb6..388df7082 100644
--- a/netbox/ipam/api/serializers_/services.py
+++ b/netbox/ipam/api/serializers_/services.py
@@ -1,7 +1,8 @@
 from django.contrib.contenttypes.models import ContentType
+from rest_framework import serializers
 
 from ipam.choices import *
-from ipam.constants import SERVICE_ASSIGNMENT_MODELS
+from ipam.constants import SERVICE_ASSIGNMENT_MODELS, SERVICE_PORT_MAX, SERVICE_PORT_MIN
 from ipam.models import IPAddress, Service, ServiceTemplate
 from netbox.api.fields import ChoiceField, ContentTypeField, SerializedPKRelatedField
 from netbox.api.gfk_fields import GFKSerializerField
@@ -10,25 +11,60 @@ from netbox.api.serializers import PrimaryModelSerializer
 from .ip import IPAddressSerializer
 
 __all__ = (
+    'ServicePortSerializer',
     'ServiceSerializer',
     'ServiceTemplateSerializer',
 )
 
 
-class ServiceTemplateSerializer(PrimaryModelSerializer):
-    protocol = ChoiceField(choices=ServiceProtocolChoices, required=False)
+class ServicePortSerializer(serializers.Serializer):
+    """
+    A single protocol/port assignment on a service.
+    """
+    protocol = ChoiceField(choices=ServiceProtocolChoices)
+    port = serializers.IntegerField(min_value=SERVICE_PORT_MIN, max_value=SERVICE_PORT_MAX)
+
+
+class ServiceSerializerBase(PrimaryModelSerializer):
+    port_assignments = ServicePortSerializer(many=True, required=False)
+
+    # Deprecated fields, retained for backward compatibility. On read they are derived from
+    # port_assignments (protocol is null when the service mixes protocols). On write they are
+    # translated into port_assignments, unless port_assignments is provided explicitly.
+    protocol = ChoiceField(choices=ServiceProtocolChoices, required=False, allow_null=True)
+    ports = serializers.ListField(
+        child=serializers.IntegerField(min_value=SERVICE_PORT_MIN, max_value=SERVICE_PORT_MAX),
+        required=False
+    )
+
+    def validate(self, data):
+        # Translate the deprecated protocol/ports fields into port_assignments before model
+        # validation runs (the model has no protocol/ports attributes to assign).
+        if 'port_assignments' in data:
+            data.pop('protocol', None)
+            data.pop('ports', None)
+        else:
+            protocol = data.pop('protocol', None)
+            ports = data.pop('ports', None)
+            if protocol is not None and ports is not None:
+                data['port_assignments'] = [
+                    {'protocol': protocol, 'port': port} for port in ports
+                ]
+        return super().validate(data)
+
+
+class ServiceTemplateSerializer(ServiceSerializerBase):
 
     class Meta:
         model = ServiceTemplate
         fields = [
-            'id', 'url', 'display_url', 'display', 'name', 'protocol', 'ports', 'description', 'owner', 'comments',
-            'tags', 'custom_fields', 'created', 'last_updated',
+            'id', 'url', 'display_url', 'display', 'name', 'port_assignments', 'protocol', 'ports', 'description',
+            'owner', 'comments', 'tags', 'custom_fields', 'created', 'last_updated',
         ]
-        brief_fields = ('id', 'url', 'display', 'name', 'protocol', 'ports', 'description')
+        brief_fields = ('id', 'url', 'display', 'name', 'port_assignments', 'protocol', 'ports', 'description')
 
 
-class ServiceSerializer(PrimaryModelSerializer):
-    protocol = ChoiceField(choices=ServiceProtocolChoices, required=False)
+class ServiceSerializer(ServiceSerializerBase):
     ipaddresses = SerializedPKRelatedField(
         queryset=IPAddress.objects.all(),
         serializer=IPAddressSerializer,
@@ -45,7 +81,7 @@ class ServiceSerializer(PrimaryModelSerializer):
         model = Service
         fields = [
             'id', 'url', 'display_url', 'display', 'parent_object_type', 'parent_object_id', 'parent', 'name',
-            'protocol', 'ports', 'ipaddresses', 'description', 'owner', 'comments', 'tags', 'custom_fields',
-            'created', 'last_updated',
+            'port_assignments', 'protocol', 'ports', 'ipaddresses', 'description', 'owner', 'comments', 'tags',
+            'custom_fields', 'created', 'last_updated',
         ]
-        brief_fields = ('id', 'url', 'display', 'name', 'protocol', 'ports', 'description')
+        brief_fields = ('id', 'url', 'display', 'name', 'port_assignments', 'protocol', 'ports', 'description')
diff --git a/netbox/ipam/filtersets.py b/netbox/ipam/filtersets.py
index c95e76d14..fd780298f 100644
--- a/netbox/ipam/filtersets.py
+++ b/netbox/ipam/filtersets.py
@@ -22,7 +22,6 @@ from utilities.filters import (
     MultiValueCharFilter,
     MultiValueContentTypeFilter,
     MultiValueNumberFilter,
-    NumericArrayFilter,
     TreeNodeMultipleChoiceFilter,
 )
 from utilities.filtersets import register_filterset
@@ -1206,16 +1205,43 @@ class VLANTranslationRuleFilterSet(NetBoxModelFilterSet):
         return queryset.filter(qs_filter)
 
 
-@register_filterset
-class ServiceTemplateFilterSet(PrimaryModelFilterSet):
-    port = NumericArrayFilter(
-        field_name='ports',
-        lookup_expr='contains'
+class ServicePortFilterMixin(django_filters.FilterSet):
+    """
+    Shared protocol/port filters operating on the port_assignments JSON field.
+    """
+    protocol = django_filters.MultipleChoiceFilter(
+        choices=ServiceProtocolChoices,
+        method='filter_protocol',
+        label=_('Protocol'),
     )
+    port = MultiValueNumberFilter(
+        method='filter_port',
+        label=_('Port'),
+    )
+
+    def filter_protocol(self, queryset, name, value):
+        if not value:
+            return queryset
+        query = Q()
+        for protocol in value:
+            query |= Q(port_assignments__contains=[{'protocol': protocol}])
+        return queryset.filter(query)
+
+    def filter_port(self, queryset, name, value):
+        if not value:
+            return queryset
+        query = Q()
+        for port in value:
+            query |= Q(port_assignments__contains=[{'port': int(port)}])
+        return queryset.filter(query)
+
+
+@register_filterset
+class ServiceTemplateFilterSet(ServicePortFilterMixin, PrimaryModelFilterSet):
 
     class Meta:
         model = ServiceTemplate
-        fields = ('id', 'name', 'protocol', 'description')
+        fields = ('id', 'name', 'description')
 
     def search(self, queryset, name, value):
         if not value.strip():
@@ -1228,7 +1254,7 @@ class ServiceTemplateFilterSet(PrimaryModelFilterSet):
 
 
 @register_filterset
-class ServiceFilterSet(ContactModelFilterSet, PrimaryModelFilterSet):
+class ServiceFilterSet(ServicePortFilterMixin, ContactModelFilterSet, PrimaryModelFilterSet):
     parent_object_type = MultiValueContentTypeFilter()
     device = MultiValueCharFilter(
         method='filter_device',
@@ -1271,14 +1297,9 @@ class ServiceFilterSet(ContactModelFilterSet, PrimaryModelFilterSet):
         to_field_name='address',
         label=_('IP address'),
     )
-    port = NumericArrayFilter(
-        field_name='ports',
-        lookup_expr='contains'
-    )
-
     class Meta:
         model = Service
-        fields = ('id', 'name', 'protocol', 'description', 'parent_object_type', 'parent_object_id')
+        fields = ('id', 'name', 'description', 'parent_object_type', 'parent_object_id')
 
     def search(self, queryset, name, value):
         if not value.strip():
diff --git a/netbox/ipam/forms/bulk_import.py b/netbox/ipam/forms/bulk_import.py
index 43a679f84..ea8add87a 100644
--- a/netbox/ipam/forms/bulk_import.py
+++ b/netbox/ipam/forms/bulk_import.py
@@ -14,6 +14,7 @@ from utilities.forms.fields import (
     CSVContentTypeField,
     CSVModelChoiceField,
     CSVModelMultipleChoiceField,
+    NumericArrayField,
     NumericRangeArrayField,
     SlugField,
 )
@@ -586,19 +587,41 @@ class VLANTranslationRuleImportForm(NetBoxModelImportForm):
         fields = ('policy', 'local_vid', 'remote_vid')
 
 
-class ServiceTemplateImportForm(PrimaryModelImportForm):
+class ServicePortImportMixin:
+    """
+    Compose a service's port_assignments from the deprecated protocol and ports import columns.
+    """
+    def clean(self):
+        super().clean()
+        protocol = self.cleaned_data.get('protocol')
+        ports = self.cleaned_data.get('ports')
+        if protocol and ports:
+            # Buffer the values for recomposition into port_assignments during model validation
+            self.instance.protocol = protocol
+            self.instance.ports = ports
+
+
+class ServiceTemplateImportForm(ServicePortImportMixin, PrimaryModelImportForm):
     protocol = CSVChoiceField(
         label=_('Protocol'),
         choices=ServiceProtocolChoices,
         help_text=_('IP protocol')
     )
+    ports = NumericArrayField(
+        label=_('Ports'),
+        base_field=forms.IntegerField(
+            min_value=SERVICE_PORT_MIN,
+            max_value=SERVICE_PORT_MAX
+        ),
+        help_text=_('Comma-separated list of one or more port numbers')
+    )
 
     class Meta:
         model = ServiceTemplate
         fields = ('name', 'protocol', 'ports', 'description', 'owner', 'comments', 'tags')
 
 
-class ServiceImportForm(PrimaryModelImportForm):
+class ServiceImportForm(ServicePortImportMixin, PrimaryModelImportForm):
     parent_object_type = CSVContentTypeField(
         queryset=ContentType.objects.filter(SERVICE_ASSIGNMENT_MODELS),
         required=True,
@@ -620,6 +643,14 @@ class ServiceImportForm(PrimaryModelImportForm):
         choices=ServiceProtocolChoices,
         help_text=_('IP protocol')
     )
+    ports = NumericArrayField(
+        label=_('Ports'),
+        base_field=forms.IntegerField(
+            min_value=SERVICE_PORT_MIN,
+            max_value=SERVICE_PORT_MAX
+        ),
+        help_text=_('Comma-separated list of one or more port numbers')
+    )
     ipaddresses = CSVModelMultipleChoiceField(
         queryset=IPAddress.objects.all(),
         required=False,
diff --git a/netbox/ipam/forms/filtersets.py b/netbox/ipam/forms/filtersets.py
index 0bd60ef4f..39ed69ced 100644
--- a/netbox/ipam/forms/filtersets.py
+++ b/netbox/ipam/forms/filtersets.py
@@ -643,9 +643,9 @@ class ServiceTemplateFilterForm(PrimaryModelFilterSetForm):
         FieldSet('protocol', 'port', name=_('Attributes')),
         FieldSet('owner_group_id', 'owner_id', name=_('Ownership')),
     )
-    protocol = forms.ChoiceField(
+    protocol = forms.MultipleChoiceField(
         label=_('Protocol'),
-        choices=add_blank_choice(ServiceProtocolChoices),
+        choices=ServiceProtocolChoices,
         required=False
     )
     port = forms.IntegerField(
diff --git a/netbox/ipam/forms/model_forms.py b/netbox/ipam/forms/model_forms.py
index 5a5a0ad81..e7d835680 100644
--- a/netbox/ipam/forms/model_forms.py
+++ b/netbox/ipam/forms/model_forms.py
@@ -800,10 +800,37 @@ class VLANTranslationRuleForm(NetBoxModelForm):
         ]
 
 
-class ServiceTemplateForm(PrimaryModelForm):
-    protocol = ChoiceField(
-        label=_('Protocol'),
+class ServicePortAssignmentsMixin:
+    """
+    Shared handling for composing a service's port_assignments from a set of protocols and ports. Each
+    selected protocol is paired with every port (the cartesian product).
+    """
+    def _init_port_assignments(self):
+        # Populate the protocols/ports selections from an existing instance
+        if self.instance and self.instance.pk:
+            self.initial.setdefault(
+                'protocols', sorted({a['protocol'] for a in self.instance.port_assignments})
+            )
+            self.initial.setdefault(
+                'ports', sorted({a['port'] for a in self.instance.port_assignments})
+            )
+
+    def _apply_port_assignments(self):
+        protocols = self.cleaned_data.get('protocols')
+        ports = self.cleaned_data.get('ports')
+        if protocols and ports:
+            self.instance.port_assignments = [
+                {'protocol': protocol, 'port': port}
+                for port in ports
+                for protocol in protocols
+            ]
+
+
+class ServiceTemplateForm(ServicePortAssignmentsMixin, PrimaryModelForm):
+    protocols = forms.MultipleChoiceField(
         choices=ServiceProtocolChoices,
+        label=_('Protocols'),
+        help_text=_("Each selected protocol is paired with every port below to form the port assignments.")
     )
     ports = NumericArrayField(
         label=_('Ports'),
@@ -815,19 +842,23 @@ class ServiceTemplateForm(PrimaryModelForm):
     )
 
     fieldsets = (
-        FieldSet('name', 'protocol', 'ports', 'description', 'tags', name=_('Application Service Template')),
+        FieldSet('name', 'protocols', 'ports', 'description', 'tags', name=_('Application Service Template')),
     )
 
     class Meta:
         model = ServiceTemplate
-        fields = ('name', 'protocol', 'ports', 'description', 'owner', 'comments', 'tags')
+        fields = ('name', 'description', 'owner', 'comments', 'tags')
+
+    def __init__(self, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+        self._init_port_assignments()
+
+    def clean(self):
+        super().clean()
+        self._apply_port_assignments()
 
 
-class ServiceForm(GenericObjectFormMixin, PrimaryModelForm):
-    protocol = ChoiceField(
-        label=_('Protocol'),
-        choices=ServiceProtocolChoices,
-    )
+class ServiceForm(ServicePortAssignmentsMixin, GenericObjectFormMixin, PrimaryModelForm):
     parent = GenericObjectChoiceField(
         label=_('Parent'),
         content_type_queryset=ContentType.objects.filter(SERVICE_ASSIGNMENT_MODELS),
@@ -835,6 +866,11 @@ class ServiceForm(GenericObjectFormMixin, PrimaryModelForm):
         selector=True,
         hx_target_id='service',
     )
+    protocols = forms.MultipleChoiceField(
+        choices=ServiceProtocolChoices,
+        label=_('Protocols'),
+        help_text=_("Each selected protocol is paired with every port below to form the port assignments.")
+    )
     ports = NumericArrayField(
         label=_('Ports'),
         base_field=forms.IntegerField(
@@ -852,7 +888,7 @@ class ServiceForm(GenericObjectFormMixin, PrimaryModelForm):
     fieldsets = (
         FieldSet(
             'parent', 'name',
-            InlineFields('protocol', 'ports', label=_('Port(s)')),
+            InlineFields('protocols', 'ports', label=_('Port(s)')),
             'ipaddresses', 'description', 'tags', name=_('Application Service'),
             html_id='service',
         ),
@@ -861,11 +897,12 @@ class ServiceForm(GenericObjectFormMixin, PrimaryModelForm):
     class Meta:
         model = Service
         fields = [
-            'name', 'protocol', 'ports', 'ipaddresses', 'description', 'owner', 'comments', 'tags',
+            'name', 'ipaddresses', 'description', 'owner', 'comments', 'tags',
         ]
 
     def __init__(self, *args, **kwargs):
         super().__init__(*args, **kwargs)
+        self._init_port_assignments()
 
         # Filter the IP address selector to those belonging to the selected parent. The object subwidget is
         # named "parent_object_id", so the dynamic param references "$parent_object_id".
@@ -877,6 +914,10 @@ class ServiceForm(GenericObjectFormMixin, PrimaryModelForm):
         elif parent_model is FHRPGroup:
             self.fields['ipaddresses'].widget.add_query_params({'fhrpgroup_id': '$parent_object_id'})
 
+    def clean(self):
+        super().clean()
+        self._apply_port_assignments()
+
 
 class ServiceCreateForm(ServiceForm):
     service_template = DynamicModelChoiceField(
@@ -890,7 +931,7 @@ class ServiceCreateForm(ServiceForm):
             'parent',
             TabbedGroups(
                 FieldSet('service_template', name=_('From Template')),
-                FieldSet('name', 'protocol', 'ports', name=_('Custom')),
+                FieldSet('name', 'protocols', 'ports', name=_('Custom')),
             ),
             'ipaddresses', 'description', 'tags', name=_('Application Service'),
             html_id='service',
@@ -899,7 +940,7 @@ class ServiceCreateForm(ServiceForm):
 
     class Meta(ServiceForm.Meta):
         fields = [
-            'service_template', 'name', 'protocol', 'ports', 'ipaddresses', 'description',
+            'service_template', 'name', 'ipaddresses', 'description',
             'comments', 'tags',
         ]
 
@@ -907,21 +948,21 @@ class ServiceCreateForm(ServiceForm):
         super().__init__(*args, **kwargs)
 
         # Fields which may be populated from a ServiceTemplate are not required
-        for field in ('name', 'protocol', 'ports'):
+        for field in ('name', 'protocols', 'ports'):
             self.fields[field].required = False
             self.fields[field].widget.is_required = False
 
     def clean(self):
         super().clean()
-        if self.cleaned_data['service_template']:
+        if self.cleaned_data.get('service_template'):
             # Create a new Service from the specified template
             service_template = self.cleaned_data['service_template']
             self.cleaned_data['name'] = service_template.name
-            self.cleaned_data['protocol'] = service_template.protocol
-            self.cleaned_data['ports'] = service_template.ports
-            if not self.cleaned_data['description']:
+            self.instance.port_assignments = service_template.port_assignments
+            if not self.cleaned_data.get('description'):
                 self.cleaned_data['description'] = service_template.description
-        elif not all(self.cleaned_data[f] for f in ('name', 'protocol', 'ports')):
+        elif not (self.cleaned_data.get('name') and self.cleaned_data.get('protocols') and
+                  self.cleaned_data.get('ports')):
             raise forms.ValidationError(
                 _("Must specify name, protocol, and port(s) if not using an application service template.")
             )
diff --git a/netbox/ipam/graphql/filter_mixins.py b/netbox/ipam/graphql/filter_mixins.py
index 130c6208b..0c029d2a2 100644
--- a/netbox/ipam/graphql/filter_mixins.py
+++ b/netbox/ipam/graphql/filter_mixins.py
@@ -1,13 +1,10 @@
-from dataclasses import dataclass
 from typing import TYPE_CHECKING, Annotated
 
 import strawberry
 import strawberry_django
-from strawberry_django import BaseFilterLookup
+from django.db.models import Q
 
 if TYPE_CHECKING:
-    from netbox.graphql.filter_lookups import IntegerLookup
-
     from .enums import *
 
 __all__ = (
@@ -15,11 +12,26 @@ __all__ = (
 )
 
 
-@dataclass
 class ServiceFilterMixin:
-    protocol: BaseFilterLookup[Annotated['ServiceProtocolEnum', strawberry.lazy('ipam.graphql.enums')]] | None = (
-        strawberry_django.filter_field()
-    )
-    ports: Annotated['IntegerLookup', strawberry.lazy('netbox.graphql.filter_lookups')] | None = (
-        strawberry_django.filter_field()
-    )
+
+    @strawberry_django.filter_field()
+    def protocol(
+        self,
+        value: list[Annotated['ServiceProtocolEnum', strawberry.lazy('ipam.graphql.enums')]],
+        prefix,
+    ) -> Q:
+        if not value:
+            return Q()
+        q = Q()
+        for protocol in value:
+            q |= Q(**{f'{prefix}port_assignments__contains': [{'protocol': protocol.value}]})
+        return q
+
+    @strawberry_django.filter_field()
+    def port(self, value: list[int], prefix) -> Q:
+        if not value:
+            return Q()
+        q = Q()
+        for port in value:
+            q |= Q(**{f'{prefix}port_assignments__contains': [{'port': port}]})
+        return q
diff --git a/netbox/ipam/graphql/types.py b/netbox/ipam/graphql/types.py
index f17c9c72e..46704f859 100644
--- a/netbox/ipam/graphql/types.py
+++ b/netbox/ipam/graphql/types.py
@@ -10,6 +10,7 @@ from ipam import models
 from netbox.graphql.scalars import BigInt
 from netbox.graphql.types import BaseObjectType, NetBoxObjectType, OrganizationalObjectType, PrimaryObjectType
 
+from .enums import ServiceProtocolEnum
 from .filters import *
 from .mixins import IPAddressesMixin
 
@@ -249,9 +250,18 @@ class RouteTargetType(PrimaryObjectType):
     pagination=True
 )
 class ServiceType(ContactsMixin, PrimaryObjectType):
-    ports: list[int]
+    # port_assignments (a JSONField) is auto-exposed as a JSON scalar
     ipaddresses: list[Annotated['IPAddressType', strawberry.lazy('ipam.graphql.types')]]
 
+    # Deprecated backward-compatibility fields, derived from port_assignments
+    @strawberry.field
+    def ports(self) -> list[int]:
+        return self.ports
+
+    @strawberry.field
+    def protocol(self) -> ServiceProtocolEnum | None:
+        return ServiceProtocolEnum(self.protocol) if self.protocol else None
+
     @strawberry_django.field(prefetch_related='parent')
     def parent(self) -> Annotated[
         Annotated['DeviceType', strawberry.lazy('dcim.graphql.types')]
@@ -269,7 +279,16 @@ class ServiceType(ContactsMixin, PrimaryObjectType):
     pagination=True
 )
 class ServiceTemplateType(PrimaryObjectType):
-    ports: list[int]
+    # port_assignments (a JSONField) is auto-exposed as a JSON scalar
+
+    # Deprecated backward-compatibility fields, derived from port_assignments
+    @strawberry.field
+    def ports(self) -> list[int]:
+        return self.ports
+
+    @strawberry.field
+    def protocol(self) -> ServiceProtocolEnum | None:
+        return ServiceProtocolEnum(self.protocol) if self.protocol else None
 
 
 @strawberry_django.type(
diff --git a/netbox/ipam/migrations/0094_alter_service_options_and_more.py b/netbox/ipam/migrations/0094_alter_service_options_and_more.py
new file mode 100644
index 000000000..5ce83d5c7
--- /dev/null
+++ b/netbox/ipam/migrations/0094_alter_service_options_and_more.py
@@ -0,0 +1,87 @@
+# Generated by Django 6.0.6 on 2026-07-01 21:08
+
+from django.db import migrations, models
+
+
+def populate_port_assignments(apps, schema_editor):
+    """
+    Populate port_assignments from the legacy protocol and ports fields.
+    """
+    for model_name in ('Service', 'ServiceTemplate'):
+        model = apps.get_model('ipam', model_name)
+        for obj in model.objects.all().iterator():
+            obj.port_assignments = [
+                {'protocol': obj.protocol, 'port': port}
+                for port in (obj.ports or [])
+            ]
+            obj.save(update_fields=['port_assignments'])
+
+
+def restore_protocol_ports(apps, schema_editor):
+    """
+    Reverse: reconstruct the legacy protocol and ports fields from port_assignments. This is lossy
+    for services which mix protocols (only the first assignment's protocol is retained).
+    """
+    for model_name in ('Service', 'ServiceTemplate'):
+        model = apps.get_model('ipam', model_name)
+        for obj in model.objects.all().iterator():
+            assignments = obj.port_assignments or []
+            obj.protocol = assignments[0]['protocol'] if assignments else ''
+            obj.ports = sorted({assignment['port'] for assignment in assignments})
+            obj.save(update_fields=['protocol', 'ports'])
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('contenttypes', '0002_remove_content_type_name'),
+        ('extras', '0140_imageattachment_image_size'),
+        ('ipam', '0093_denormalization_triggers'),
+        ('users', '0016_default_ordering_indexes'),
+    ]
+
+    operations = [
+        # Add the new field to both models
+        migrations.AddField(
+            model_name='service',
+            name='port_assignments',
+            field=models.JSONField(blank=True, default=list),
+        ),
+        migrations.AddField(
+            model_name='servicetemplate',
+            name='port_assignments',
+            field=models.JSONField(blank=True, default=list),
+        ),
+        # Copy existing protocol/ports data into port_assignments
+        migrations.RunPython(populate_port_assignments, restore_protocol_ports),
+        # Remove the legacy protocol/ports fields and their index
+        migrations.RemoveIndex(
+            model_name='service',
+            name='ipam_servic_protoco_e2901d_idx',
+        ),
+        migrations.RemoveField(
+            model_name='service',
+            name='protocol',
+        ),
+        migrations.RemoveField(
+            model_name='service',
+            name='ports',
+        ),
+        migrations.RemoveField(
+            model_name='servicetemplate',
+            name='protocol',
+        ),
+        migrations.RemoveField(
+            model_name='servicetemplate',
+            name='ports',
+        ),
+        # Update ordering and index to reflect the removal of protocol
+        migrations.AddIndex(
+            model_name='service',
+            index=models.Index(fields=['_ports_lowest', 'id'], name='ipam_servic__ports__10a2cc_idx'),
+        ),
+        migrations.AlterModelOptions(
+            name='service',
+            options={'ordering': ('_ports_lowest', 'id')},
+        ),
+    ]
diff --git a/netbox/ipam/models/services.py b/netbox/ipam/models/services.py
index 9eb0b928d..1fd7c8b3f 100644
--- a/netbox/ipam/models/services.py
+++ b/netbox/ipam/models/services.py
@@ -1,6 +1,5 @@
 from django.contrib.contenttypes.fields import GenericForeignKey
-from django.contrib.postgres.fields import ArrayField
-from django.core.validators import MaxValueValidator, MinValueValidator
+from django.core.exceptions import ValidationError
 from django.db import models
 from django.utils.translation import gettext_lazy as _
 
@@ -17,19 +16,11 @@ __all__ = (
 
 
 class ServiceBase(models.Model):
-    protocol = models.CharField(
-        verbose_name=_('protocol'),
-        max_length=50,
-        choices=ServiceProtocolChoices
-    )
-    ports = ArrayField(
-        base_field=models.PositiveIntegerField(
-            validators=[
-                MinValueValidator(SERVICE_PORT_MIN),
-                MaxValueValidator(SERVICE_PORT_MAX)
-            ]
-        ),
-        verbose_name=_('port numbers')
+    port_assignments = models.JSONField(
+        verbose_name=_('port assignments'),
+        default=list,
+        blank=True,
+        help_text=_('A list of protocol/port assignments, e.g. [{"protocol": "tcp", "port": 53}]')
     )
     _ports_lowest = models.PositiveIntegerField(
         null=True,
@@ -40,19 +31,115 @@ class ServiceBase(models.Model):
         abstract = True
 
     def save(self, *args, **kwargs):
+        # Compose port_assignments from any deprecated protocol/ports values assigned directly
+        self._recompose_port_assignments()
         # On saving find the smallest port and save for default ordering
-        self._ports_lowest = min(self.ports) if self.ports else None
+        self._ports_lowest = min(
+            (assignment['port'] for assignment in self.port_assignments), default=None
+        )
         update_fields = kwargs.get('update_fields')
         if update_fields is not None and '_ports_lowest' not in update_fields:
             kwargs['update_fields'] = list(update_fields) + ['_ports_lowest']
         super().save(*args, **kwargs)
 
     def __str__(self):
-        return f'{self.name} ({self.get_protocol_display()}/{self.port_list})'
+        return f'{self.name} ({self.port_list})'
+
+    def clean(self):
+        super().clean()
+
+        # Compose port_assignments from any deprecated protocol/ports values assigned directly
+        self._recompose_port_assignments()
+
+        if not self.port_assignments:
+            raise ValidationError({
+                'port_assignments': _("At least one protocol/port assignment must be defined.")
+            })
+
+        valid_protocols = ServiceProtocolChoices.values()
+        for assignment in self.port_assignments:
+            if not isinstance(assignment, dict) or set(assignment) != {'protocol', 'port'}:
+                raise ValidationError({
+                    'port_assignments': _("Each assignment must define exactly a protocol and a port.")
+                })
+            if assignment['protocol'] not in valid_protocols:
+                raise ValidationError({
+                    'port_assignments': _("Invalid protocol: {protocol}").format(protocol=assignment['protocol'])
+                })
+            port = assignment['port']
+            if not isinstance(port, int) or not SERVICE_PORT_MIN <= port <= SERVICE_PORT_MAX:
+                raise ValidationError({
+                    'port_assignments': _("Invalid port number: {port}").format(port=port)
+                })
+
+    @property
+    def protocol(self):
+        """
+        Deprecated backward-compatibility accessor. Returns the single protocol shared by all port
+        assignments, or None if the service mixes protocols (or has no assignments).
+        """
+        protocols = {assignment['protocol'] for assignment in self.port_assignments}
+        return protocols.pop() if len(protocols) == 1 else None
+
+    @protocol.setter
+    def protocol(self, value):
+        # Deprecated: buffer the value for recomposition into port_assignments (see save()/clean())
+        self._legacy_protocol = value
+
+    @property
+    def ports(self):
+        """
+        Deprecated backward-compatibility accessor. Returns a sorted list of all assigned port numbers.
+        """
+        return sorted({assignment['port'] for assignment in self.port_assignments})
+
+    @ports.setter
+    def ports(self, value):
+        # Deprecated: buffer the value for recomposition into port_assignments (see save()/clean())
+        self._legacy_ports = list(value) if value else []
+
+    def _recompose_port_assignments(self):
+        """
+        If deprecated protocol and/or ports values were assigned directly (e.g. via bulk edit),
+        rebuild port_assignments as the cartesian product of the effective protocols and ports.
+        Missing values fall back to those already present in port_assignments.
+        """
+        has_protocol = hasattr(self, '_legacy_protocol')
+        has_ports = hasattr(self, '_legacy_ports')
+        if not (has_protocol or has_ports):
+            return
+
+        if has_protocol and self._legacy_protocol:
+            protocols = [self._legacy_protocol]
+        else:
+            protocols = sorted({assignment['protocol'] for assignment in self.port_assignments})
+        if has_ports:
+            ports = self._legacy_ports
+        else:
+            ports = sorted({assignment['port'] for assignment in self.port_assignments})
+
+        self.port_assignments = [
+            {'protocol': protocol, 'port': port}
+            for port in ports
+            for protocol in protocols
+        ]
+
+        if has_protocol:
+            del self._legacy_protocol
+        if has_ports:
+            del self._legacy_ports
 
     @property
     def port_list(self):
-        return array_to_string(self.ports)
+        # Group ports by protocol for compact display, e.g. "TCP/80, 443; UDP/53"
+        protocol_labels = dict(ServiceProtocolChoices)
+        grouped = {}
+        for assignment in self.port_assignments:
+            grouped.setdefault(assignment['protocol'], []).append(assignment['port'])
+        return '; '.join(
+            f'{protocol_labels.get(protocol, protocol)}/{array_to_string(sorted(ports))}'
+            for protocol, ports in grouped.items()
+        )
 
 
 class ServiceTemplate(ServiceBase, PrimaryModel):
@@ -99,14 +186,14 @@ class Service(ContactsMixin, ServiceBase, PrimaryModel):
     )
 
     clone_fields = (
-        'protocol', 'ports', 'description', 'parent', 'ipaddresses',
+        'port_assignments', 'description', 'parent', 'ipaddresses',
     )
 
     class Meta:
         indexes = (
-            models.Index(fields=('protocol', '_ports_lowest', 'id')),  # Default ordering
+            models.Index(fields=('_ports_lowest', 'id')),  # Default ordering
             models.Index(fields=('parent_object_type', 'parent_object_id')),
         )
-        ordering = ('protocol', '_ports_lowest', 'id')
+        ordering = ('_ports_lowest', 'id')
         verbose_name = _('application service')
         verbose_name_plural = _('application services')
diff --git a/netbox/ipam/tables/services.py b/netbox/ipam/tables/services.py
index e74317663..2191b0c26 100644
--- a/netbox/ipam/tables/services.py
+++ b/netbox/ipam/tables/services.py
@@ -16,10 +16,16 @@ class ServiceTemplateTable(PrimaryModelTable):
         verbose_name=_('Name'),
         linkify=True
     )
+    # Deprecated: derived from port_assignments (empty when the service mixes protocols)
+    protocol = tables.Column(
+        verbose_name=_('Protocol'),
+        accessor=tables.A('protocol'),
+        orderable=False,
+    )
     ports = tables.Column(
         verbose_name=_('Ports'),
         accessor=tables.A('port_list'),
-        order_by=tables.A('ports'),
+        order_by=tables.A('_ports_lowest'),
     )
     tags = columns.TagColumn(
         url_name='ipam:servicetemplate_list'
@@ -30,7 +36,7 @@ class ServiceTemplateTable(PrimaryModelTable):
         fields = (
             'pk', 'id', 'name', 'protocol', 'ports', 'description', 'comments', 'tags', 'created', 'last_updated',
         )
-        default_columns = ('pk', 'name', 'protocol', 'ports', 'description')
+        default_columns = ('pk', 'name', 'ports', 'description')
 
 
 class ServiceTable(ContactsColumnMixin, PrimaryModelTable):
@@ -43,10 +49,16 @@ class ServiceTable(ContactsColumnMixin, PrimaryModelTable):
         linkify=True,
         order_by=('device', 'virtual_machine')
     )
+    # Deprecated: derived from port_assignments (empty when the service mixes protocols)
+    protocol = tables.Column(
+        verbose_name=_('Protocol'),
+        accessor=tables.A('protocol'),
+        orderable=False,
+    )
     ports = tables.Column(
         verbose_name=_('Ports'),
         accessor=tables.A('port_list'),
-        order_by=tables.A('ports'),
+        order_by=tables.A('_ports_lowest'),
     )
     tags = columns.TagColumn(
         url_name='ipam:service_list'
@@ -58,4 +70,4 @@ class ServiceTable(ContactsColumnMixin, PrimaryModelTable):
             'pk', 'id', 'name', 'parent', 'protocol', 'ports', 'ipaddresses', 'description', 'contacts', 'comments',
             'tags', 'created', 'last_updated',
         )
-        default_columns = ('pk', 'name', 'parent', 'protocol', 'ports', 'description')
+        default_columns = ('pk', 'name', 'parent', 'ports', 'description')
diff --git a/netbox/ipam/tests/test_api.py b/netbox/ipam/tests/test_api.py
index a4f54fbb5..7e49114d0 100644
--- a/netbox/ipam/tests/test_api.py
+++ b/netbox/ipam/tests/test_api.py
@@ -1418,7 +1418,7 @@ class VLANTranslationRuleTestCase(APIViewTestCases.APIViewTestCase):
 
 class ServiceTemplateTestCase(APIViewTestCases.APIViewTestCase):
     model = ServiceTemplate
-    brief_fields = ['description', 'display', 'id', 'name', 'ports', 'protocol', 'url']
+    brief_fields = ['description', 'display', 'id', 'name', 'port_assignments', 'ports', 'protocol', 'url']
     bulk_update_data = {
         'description': 'New description',
     }
@@ -1427,9 +1427,18 @@ class ServiceTemplateTestCase(APIViewTestCases.APIViewTestCase):
     @classmethod
     def setUpTestData(cls):
         service_templates = (
-            ServiceTemplate(name='Service Template 1', protocol=ServiceProtocolChoices.PROTOCOL_TCP, ports=[1, 2]),
-            ServiceTemplate(name='Service Template 2', protocol=ServiceProtocolChoices.PROTOCOL_TCP, ports=[3, 4]),
-            ServiceTemplate(name='Service Template 3', protocol=ServiceProtocolChoices.PROTOCOL_TCP, ports=[5, 6]),
+            ServiceTemplate(name='Service Template 1', port_assignments=[
+                {'protocol': ServiceProtocolChoices.PROTOCOL_TCP, 'port': 1},
+                {'protocol': ServiceProtocolChoices.PROTOCOL_TCP, 'port': 2},
+            ]),
+            ServiceTemplate(name='Service Template 2', port_assignments=[
+                {'protocol': ServiceProtocolChoices.PROTOCOL_TCP, 'port': 3},
+                {'protocol': ServiceProtocolChoices.PROTOCOL_TCP, 'port': 4},
+            ]),
+            ServiceTemplate(name='Service Template 3', port_assignments=[
+                {'protocol': ServiceProtocolChoices.PROTOCOL_TCP, 'port': 5},
+                {'protocol': ServiceProtocolChoices.PROTOCOL_TCP, 'port': 6},
+            ]),
         )
         ServiceTemplate.objects.bulk_create(service_templates)
 
@@ -1454,7 +1463,7 @@ class ServiceTemplateTestCase(APIViewTestCases.APIViewTestCase):
 
 class ServiceTestCase(APIViewTestCases.APIViewTestCase):
     model = Service
-    brief_fields = ['description', 'display', 'id', 'name', 'ports', 'protocol', 'url']
+    brief_fields = ['description', 'display', 'id', 'name', 'port_assignments', 'ports', 'protocol', 'url']
     bulk_update_data = {
         'description': 'New description',
     }
@@ -1474,9 +1483,15 @@ class ServiceTestCase(APIViewTestCases.APIViewTestCase):
         Device.objects.bulk_create(devices)
 
         services = (
-            Service(parent=devices[0], name='Service 1', protocol=ServiceProtocolChoices.PROTOCOL_TCP, ports=[1]),
-            Service(parent=devices[0], name='Service 2', protocol=ServiceProtocolChoices.PROTOCOL_TCP, ports=[2]),
-            Service(parent=devices[0], name='Service 3', protocol=ServiceProtocolChoices.PROTOCOL_TCP, ports=[3]),
+            Service(parent=devices[0], name='Service 1', port_assignments=[
+                {'protocol': ServiceProtocolChoices.PROTOCOL_TCP, 'port': 1},
+            ]),
+            Service(parent=devices[0], name='Service 2', port_assignments=[
+                {'protocol': ServiceProtocolChoices.PROTOCOL_TCP, 'port': 2},
+            ]),
+            Service(parent=devices[0], name='Service 3', port_assignments=[
+                {'protocol': ServiceProtocolChoices.PROTOCOL_TCP, 'port': 3},
+            ]),
         )
         Service.objects.bulk_create(services)
 
@@ -1504,6 +1519,40 @@ class ServiceTestCase(APIViewTestCases.APIViewTestCase):
             },
         ]
 
+    def test_create_with_port_assignments(self):
+        """
+        A service may be created via the new port_assignments field, mixing protocols on a port.
+        """
+        self.add_permissions('ipam.add_service')
+        device = Device.objects.first()
+        data = {
+            'parent_object_id': device.pk,
+            'parent_object_type': 'dcim.device',
+            'name': 'DNS',
+            'port_assignments': [
+                {'protocol': ServiceProtocolChoices.PROTOCOL_TCP, 'port': 53},
+                {'protocol': ServiceProtocolChoices.PROTOCOL_UDP, 'port': 53},
+            ],
+        }
+        response = self.client.post(self._get_list_url(), data, format='json', **self.header)
+        self.assertHttpStatus(response, status.HTTP_201_CREATED)
+        service = Service.objects.get(pk=response.data['id'])
+        self.assertEqual(len(service.port_assignments), 2)
+        # Deprecated protocol accessor is null for a mixed-protocol service; ports is flattened
+        self.assertIsNone(response.data['protocol'])
+        self.assertEqual(response.data['ports'], [53])
+
+    def test_backward_compatible_protocol_read(self):
+        """
+        A uniform-protocol service exposes the deprecated protocol field as a single value.
+        """
+        self.add_permissions('ipam.view_service')
+        service = Service.objects.get(name='Service 1')
+        url = self._get_detail_url(service)
+        response = self.client.get(url, **self.header)
+        self.assertEqual(response.data['protocol']['value'], ServiceProtocolChoices.PROTOCOL_TCP)
+        self.assertEqual(response.data['ports'], [1])
+
 
 class NestedObjectPermissionAPITest(APITestCase):
     """
diff --git a/netbox/ipam/tests/test_filtersets.py b/netbox/ipam/tests/test_filtersets.py
index 4e396a9f8..bcfd4ee12 100644
--- a/netbox/ipam/tests/test_filtersets.py
+++ b/netbox/ipam/tests/test_filtersets.py
@@ -2358,43 +2358,37 @@ class VLANTranslationRuleTestCase(TestCase, ChangeLoggedFilterSetTests):
 class ServiceTemplateTestCase(TestCase, ChangeLoggedFilterSetTests):
     queryset = ServiceTemplate.objects.all()
     filterset = ServiceTemplateFilterSet
-    ignore_fields = ('ports',)
+    ignore_fields = ('port_assignments',)
 
     @classmethod
     def setUpTestData(cls):
         service_templates = (
             ServiceTemplate(
                 name='Service Template 1',
-                protocol=ServiceProtocolChoices.PROTOCOL_TCP,
-                ports=[1001],
+                port_assignments=[{'protocol': ServiceProtocolChoices.PROTOCOL_TCP, 'port': 1001}],
                 description='foobar1'
             ),
             ServiceTemplate(
                 name='Service Template 2',
-                protocol=ServiceProtocolChoices.PROTOCOL_TCP,
-                ports=[1002],
+                port_assignments=[{'protocol': ServiceProtocolChoices.PROTOCOL_TCP, 'port': 1002}],
                 description='foobar2'
             ),
             ServiceTemplate(
                 name='Service Template 3',
-                protocol=ServiceProtocolChoices.PROTOCOL_UDP,
-                ports=[1003],
+                port_assignments=[{'protocol': ServiceProtocolChoices.PROTOCOL_UDP, 'port': 1003}],
                 description='foobar3'
             ),
             ServiceTemplate(
                 name='Service Template 4',
-                protocol=ServiceProtocolChoices.PROTOCOL_TCP,
-                ports=[2001]
+                port_assignments=[{'protocol': ServiceProtocolChoices.PROTOCOL_TCP, 'port': 2001}],
             ),
             ServiceTemplate(
                 name='Service Template 5',
-                protocol=ServiceProtocolChoices.PROTOCOL_TCP,
-                ports=[2002]
+                port_assignments=[{'protocol': ServiceProtocolChoices.PROTOCOL_TCP, 'port': 2002}],
             ),
             ServiceTemplate(
                 name='Service Template 6',
-                protocol=ServiceProtocolChoices.PROTOCOL_UDP,
-                ports=[2003]
+                port_assignments=[{'protocol': ServiceProtocolChoices.PROTOCOL_UDP, 'port': 2003}],
             ),
         )
         ServiceTemplate.objects.bulk_create(service_templates)
@@ -2408,11 +2402,11 @@ class ServiceTemplateTestCase(TestCase, ChangeLoggedFilterSetTests):
         self.assertEqual(self.filterset(params, self.queryset).qs.count(), 2)
 
     def test_protocol(self):
-        params = {'protocol': ServiceProtocolChoices.PROTOCOL_TCP}
+        params = {'protocol': [ServiceProtocolChoices.PROTOCOL_TCP]}
         self.assertEqual(self.filterset(params, self.queryset).qs.count(), 4)
 
     def test_port(self):
-        params = {'port': '1001'}
+        params = {'port': [1001]}
         self.assertEqual(self.filterset(params, self.queryset).qs.count(), 1)
 
     def test_description(self):
@@ -2423,7 +2417,7 @@ class ServiceTemplateTestCase(TestCase, ChangeLoggedFilterSetTests):
 class ServiceTestCase(TestCase, ChangeLoggedFilterSetTests):
     queryset = Service.objects.all()
     filterset = ServiceFilterSet
-    ignore_fields = ('ports',)
+    ignore_fields = ('port_assignments',)
 
     @classmethod
     def setUpTestData(cls):
@@ -2472,46 +2466,39 @@ class ServiceTestCase(TestCase, ChangeLoggedFilterSetTests):
             Service(
                 parent=devices[0],
                 name='Service 1',
-                protocol=ServiceProtocolChoices.PROTOCOL_TCP,
-                ports=[1001],
+                port_assignments=[{'protocol': ServiceProtocolChoices.PROTOCOL_TCP, 'port': 1001}],
                 description='foobar1',
             ),
             Service(
                 parent=devices[1],
                 name='Service 2',
-                protocol=ServiceProtocolChoices.PROTOCOL_TCP,
-                ports=[1002],
+                port_assignments=[{'protocol': ServiceProtocolChoices.PROTOCOL_TCP, 'port': 1002}],
                 description='foobar2',
             ),
             Service(
                 parent=devices[2],
                 name='Service 3',
-                protocol=ServiceProtocolChoices.PROTOCOL_UDP,
-                ports=[1003]
+                port_assignments=[{'protocol': ServiceProtocolChoices.PROTOCOL_UDP, 'port': 1003}],
             ),
             Service(
                 parent=virtual_machines[0],
                 name='Service 4',
-                protocol=ServiceProtocolChoices.PROTOCOL_TCP,
-                ports=[2001],
+                port_assignments=[{'protocol': ServiceProtocolChoices.PROTOCOL_TCP, 'port': 2001}],
             ),
             Service(
                 parent=virtual_machines[1],
                 name='Service 5',
-                protocol=ServiceProtocolChoices.PROTOCOL_TCP,
-                ports=[2002],
+                port_assignments=[{'protocol': ServiceProtocolChoices.PROTOCOL_TCP, 'port': 2002}],
             ),
             Service(
                 parent=virtual_machines[2],
                 name='Service 6',
-                protocol=ServiceProtocolChoices.PROTOCOL_UDP,
-                ports=[2003],
+                port_assignments=[{'protocol': ServiceProtocolChoices.PROTOCOL_UDP, 'port': 2003}],
             ),
             Service(
                 parent=fhrp_group,
                 name='Service 7',
-                protocol=ServiceProtocolChoices.PROTOCOL_UDP,
-                ports=[2004],
+                port_assignments=[{'protocol': ServiceProtocolChoices.PROTOCOL_UDP, 'port': 2004}],
             ),
         )
         Service.objects.bulk_create(services)
@@ -2528,7 +2515,7 @@ class ServiceTestCase(TestCase, ChangeLoggedFilterSetTests):
         self.assertEqual(self.filterset(params, self.queryset).qs.count(), 2)
 
     def test_protocol(self):
-        params = {'protocol': ServiceProtocolChoices.PROTOCOL_TCP}
+        params = {'protocol': [ServiceProtocolChoices.PROTOCOL_TCP]}
         self.assertEqual(self.filterset(params, self.queryset).qs.count(), 4)
 
     def test_description(self):
@@ -2536,7 +2523,7 @@ class ServiceTestCase(TestCase, ChangeLoggedFilterSetTests):
         self.assertEqual(self.filterset(params, self.queryset).qs.count(), 2)
 
     def test_port(self):
-        params = {'port': '1001'}
+        params = {'port': [1001]}
         self.assertEqual(self.filterset(params, self.queryset).qs.count(), 1)
 
     def test_device(self):
diff --git a/netbox/ipam/tests/test_models.py b/netbox/ipam/tests/test_models.py
index b76a7205b..c5d4e22bd 100644
--- a/netbox/ipam/tests/test_models.py
+++ b/netbox/ipam/tests/test_models.py
@@ -1894,6 +1894,55 @@ class ServiceTemplateTestCase(TestCase):
         )
         self.assertRaises(ValidationError, template.full_clean)
 
+    def test_servicetemplate_port_assignments(self):
+        """
+        Test a template defined directly via port_assignments, mixing protocols on the same port.
+        """
+        template = ServiceTemplate(
+            name='Template 4',
+            port_assignments=[
+                {'protocol': ServiceProtocolChoices.PROTOCOL_TCP, 'port': 53},
+                {'protocol': ServiceProtocolChoices.PROTOCOL_UDP, 'port': 53},
+            ],
+        )
+        template.full_clean()
+        template.save()
+        self.assertEqual(template._ports_lowest, 53)
+        # Deprecated accessors: protocol is None when mixed, ports is the flattened set
+        self.assertIsNone(template.protocol)
+        self.assertEqual(template.ports, [53])
+
+    def test_servicetemplate_uniform_protocol_accessor(self):
+        """
+        The deprecated protocol accessor returns the single protocol when assignments are uniform.
+        """
+        template = ServiceTemplate(
+            name='Template 5',
+            port_assignments=[
+                {'protocol': ServiceProtocolChoices.PROTOCOL_TCP, 'port': 80},
+                {'protocol': ServiceProtocolChoices.PROTOCOL_TCP, 'port': 443},
+            ],
+        )
+        template.full_clean()
+        self.assertEqual(template.protocol, ServiceProtocolChoices.PROTOCOL_TCP)
+        self.assertEqual(template.ports, [80, 443])
+
+    def test_servicetemplate_invalid_port_assignment(self):
+        """
+        Invalid protocol/port values are rejected.
+        """
+        template = ServiceTemplate(
+            name='Template 6',
+            port_assignments=[{'protocol': 'bogus', 'port': 80}],
+        )
+        self.assertRaises(ValidationError, template.full_clean)
+
+        template = ServiceTemplate(
+            name='Template 7',
+            port_assignments=[{'protocol': ServiceProtocolChoices.PROTOCOL_TCP, 'port': 99999}],
+        )
+        self.assertRaises(ValidationError, template.full_clean)
+
 
 class ServiceTestCase(TestCase):
 
diff --git a/netbox/ipam/tests/test_views.py b/netbox/ipam/tests/test_views.py
index a6e1ebbc4..0b95ff931 100644
--- a/netbox/ipam/tests/test_views.py
+++ b/netbox/ipam/tests/test_views.py
@@ -1845,13 +1845,18 @@ class VLANTranslationRuleTestCase(ViewTestCases.PrimaryObjectViewTestCase):
 
 class ServiceTemplateTestCase(ViewTestCases.PrimaryObjectViewTestCase):
     model = ServiceTemplate
+    # ports is a deprecated property derived from port_assignments; exclude it from instance comparison
+    validation_excluded_fields = ('ports',)
 
     @classmethod
     def setUpTestData(cls):
         service_templates = (
-            ServiceTemplate(name='Service Template 1', protocol=ServiceProtocolChoices.PROTOCOL_TCP, ports=[101]),
-            ServiceTemplate(name='Service Template 2', protocol=ServiceProtocolChoices.PROTOCOL_TCP, ports=[102]),
-            ServiceTemplate(name='Service Template 3', protocol=ServiceProtocolChoices.PROTOCOL_TCP, ports=[103]),
+            ServiceTemplate(name='Service Template 1', port_assignments=[
+                {'protocol': ServiceProtocolChoices.PROTOCOL_TCP, 'port': 101}]),
+            ServiceTemplate(name='Service Template 2', port_assignments=[
+                {'protocol': ServiceProtocolChoices.PROTOCOL_TCP, 'port': 102}]),
+            ServiceTemplate(name='Service Template 3', port_assignments=[
+                {'protocol': ServiceProtocolChoices.PROTOCOL_TCP, 'port': 103}]),
         )
         ServiceTemplate.objects.bulk_create(service_templates)
 
@@ -1859,7 +1864,7 @@ class ServiceTemplateTestCase(ViewTestCases.PrimaryObjectViewTestCase):
 
         cls.form_data = {
             'name': 'Service Template X',
-            'protocol': ServiceProtocolChoices.PROTOCOL_UDP,
+            'protocols': [ServiceProtocolChoices.PROTOCOL_UDP],
             'ports': '104,105',
             'description': 'A new service template',
             'tags': [t.pk for t in tags],
@@ -1880,16 +1885,16 @@ class ServiceTemplateTestCase(ViewTestCases.PrimaryObjectViewTestCase):
         )
 
         cls.bulk_edit_data = {
-            'protocol': ServiceProtocolChoices.PROTOCOL_UDP,
-            'ports': '106,107',
             'description': 'New description',
+            'protocol': ServiceProtocolChoices.PROTOCOL_UDP,
         }
 
 
 class ServiceTestCase(ViewTestCases.PrimaryObjectViewTestCase):
     model = Service
-    # TODO, related to #9816, cannot validate GFK
-    validation_excluded_fields = ('device',)
+    # TODO, related to #9816, cannot validate GFK. ports is a deprecated property derived from
+    # port_assignments; exclude it from instance comparison.
+    validation_excluded_fields = ('device', 'ports')
 
     @classmethod
     def setUpTestData(cls):
@@ -1905,9 +1910,12 @@ class ServiceTestCase(ViewTestCases.PrimaryObjectViewTestCase):
         )
 
         services = (
-            Service(parent=device, name='Service 1', protocol=ServiceProtocolChoices.PROTOCOL_TCP, ports=[101]),
-            Service(parent=device, name='Service 2', protocol=ServiceProtocolChoices.PROTOCOL_TCP, ports=[102]),
-            Service(parent=device, name='Service 3', protocol=ServiceProtocolChoices.PROTOCOL_TCP, ports=[103]),
+            Service(parent=device, name='Service 1', port_assignments=[
+                {'protocol': ServiceProtocolChoices.PROTOCOL_TCP, 'port': 101}]),
+            Service(parent=device, name='Service 2', port_assignments=[
+                {'protocol': ServiceProtocolChoices.PROTOCOL_TCP, 'port': 102}]),
+            Service(parent=device, name='Service 3', port_assignments=[
+                {'protocol': ServiceProtocolChoices.PROTOCOL_TCP, 'port': 103}]),
         )
         Service.objects.bulk_create(services)
 
@@ -1924,7 +1932,7 @@ class ServiceTestCase(ViewTestCases.PrimaryObjectViewTestCase):
             'parent_content_type': ContentType.objects.get_for_model(Device).pk,
             'parent_object_id': device.pk,
             'name': 'Service X',
-            'protocol': ServiceProtocolChoices.PROTOCOL_TCP,
+            'protocols': [ServiceProtocolChoices.PROTOCOL_TCP],
             'ports': '104,105',
             'ipaddresses': [],
             'description': 'A new service',
@@ -1947,9 +1955,8 @@ class ServiceTestCase(ViewTestCases.PrimaryObjectViewTestCase):
         )
 
         cls.bulk_edit_data = {
-            'protocol': ServiceProtocolChoices.PROTOCOL_UDP,
-            'ports': '106,107',
             'description': 'New description',
+            'protocol': ServiceProtocolChoices.PROTOCOL_UDP,
         }
 
     def test_unassigned_ip_addresses(self):
diff --git a/netbox/ipam/ui/panels.py b/netbox/ipam/ui/panels.py
index 6e0f53d34..c62ed3d63 100644
--- a/netbox/ipam/ui/panels.py
+++ b/netbox/ipam/ui/panels.py
@@ -236,16 +236,14 @@ class VLANCustomerVLANsPanel(panels.ObjectsTablePanel):
 
 class ServiceTemplatePanel(panels.ObjectAttributesPanel):
     name = attrs.TextAttr('name')
-    protocol = attrs.ChoiceAttr('protocol')
-    ports = attrs.TextAttr('port_list', label=_('Ports'))
+    ports = attrs.TextAttr('port_list', label=_('Port assignments'))
     description = attrs.TextAttr('description')
 
 
 class ServicePanel(panels.ObjectAttributesPanel):
     name = attrs.TextAttr('name')
     parent = attrs.RelatedObjectAttr('parent', linkify=True)
-    protocol = attrs.ChoiceAttr('protocol')
-    ports = attrs.TextAttr('port_list', label=_('Ports'))
+    ports = attrs.TextAttr('port_list', label=_('Port assignments'))
     ip_addresses = attrs.TemplatedAttr(
         'ipaddresses',
         template_name='ipam/service/attrs/ip_addresses.html',