diff --git a/ui/src/components/IssueFiltersPopover.test.tsx b/ui/src/components/IssueFiltersPopover.test.tsx
index 4fe6a11c12..718041bd66 100644
--- a/ui/src/components/IssueFiltersPopover.test.tsx
+++ b/ui/src/components/IssueFiltersPopover.test.tsx
@@ -81,4 +81,29 @@ describe("IssueFiltersPopover", () => {
     expect(layoutGrid?.className).toContain("grid-cols-1");
     expect(popoverContent?.textContent).toContain("Live runs only");
   });
+
+  it("hides the Priority filter section while priority UI is off (PAP-411)", () => {
+    const root = createRoot(container);
+
+    act(() => {
+      root.render(
+        <IssueFiltersPopover
+          state={defaultIssueFilterState}
+          onChange={vi.fn()}
+          activeFilterCount={0}
+          agents={[{ id: "agent-1", name: "Agent One" }]}
+          projects={[{ id: "project-1", name: "Project One" }]}
+          labels={[{ id: "label-1", name: "Bug", color: "#ff0000" }]}
+          workspaces={[{ id: "workspace-1", name: "Workspace One" }]}
+          enableRoutineVisibilityFilter
+        />,
+      );
+    });
+
+    const popoverContent = container.querySelector("[data-testid='popover-content']");
+    expect(popoverContent).not.toBeNull();
+    // Status section still renders, Priority section is gated off (PAP-411).
+    expect(popoverContent?.textContent).toContain("Status");
+    expect(popoverContent?.textContent).not.toContain("Priority");
+  });
 });
diff --git a/ui/src/components/IssueFiltersPopover.tsx b/ui/src/components/IssueFiltersPopover.tsx
index d702bad7b5..d491c74c1e 100644
--- a/ui/src/components/IssueFiltersPopover.tsx
+++ b/ui/src/components/IssueFiltersPopover.tsx
@@ -6,6 +6,7 @@ import { Input } from "@/components/ui/input";
 import { Popover, PopoverContent, PopoverTrigger } from "@/components/ui/popover";
 import { Bot, Filter, HardDrive, Search, User, X } from "lucide-react";
 import { PriorityIcon } from "./PriorityIcon";
+import { SHOW_TASK_PRIORITY_UI } from "../lib/ui-flags";
 import { StatusIcon } from "./StatusIcon";
 import {
   defaultIssueFilterState,
@@ -191,6 +192,8 @@ export function IssueFiltersPopover({
                 </div>
               </div>
 
+              {/* PAP-411: Priority filter section hidden behind SHOW_TASK_PRIORITY_UI (filter state stays intact). */}
+              {SHOW_TASK_PRIORITY_UI && (
               <div className="space-y-1">
                 <span className="text-xs text-muted-foreground">Priority</span>
                 <div className="space-y-0.5">
@@ -206,6 +209,7 @@ export function IssueFiltersPopover({
                   ))}
                 </div>
               </div>
+              )}
             </div>
 
             <div className="min-w-0 space-y-3">
diff --git a/ui/src/components/IssueProperties.test.tsx b/ui/src/components/IssueProperties.test.tsx
index 5d795de7ce..40d8a2be4d 100644
--- a/ui/src/components/IssueProperties.test.tsx
+++ b/ui/src/components/IssueProperties.test.tsx
@@ -515,6 +515,25 @@ describe("IssueProperties", () => {
     act(() => root.unmount());
   });
 
+  it("hides the Priority property row while priority UI is off (PAP-411)", async () => {
+    const root = renderProperties(container, {
+      issue: createIssue({ priority: "high" }),
+      childIssues: [],
+      onUpdate: vi.fn(),
+      inline: true,
+    });
+    await flush();
+
+    await waitForAssertion(() => {
+      // The Triage section still renders the Status row...
+      expect(container.querySelector('[data-property-label="Status"]')).not.toBeNull();
+      // ...but the Priority row is gated behind SHOW_TASK_PRIORITY_UI (off).
+      expect(container.querySelector('[data-property-label="Priority"]')).toBeNull();
+    });
+
+    act(() => root.unmount());
+  });
+
   it("shows assignee and originating without responsible wording", async () => {
     mockAgentsApi.list.mockResolvedValue([{ id: "agent-1", name: "CodexCoder", status: "active", adapterType: "codex_local" }]);
     const root = renderProperties(container, {
diff --git a/ui/src/components/IssueThreadInteractionCard.tsx b/ui/src/components/IssueThreadInteractionCard.tsx
index 633f2f650b..d705484268 100644
--- a/ui/src/components/IssueThreadInteractionCard.tsx
+++ b/ui/src/components/IssueThreadInteractionCard.tsx
@@ -32,6 +32,7 @@ import { Button } from "./ui/button";
 import { Checkbox } from "./ui/checkbox";
 import { Collapsible, CollapsibleContent, CollapsibleTrigger } from "./ui/collapsible";
 import { PriorityIcon } from "./PriorityIcon";
+import { SHOW_TASK_PRIORITY_UI } from "../lib/ui-flags";
 import { Textarea } from "./ui/textarea";
 import { Tooltip, TooltipContent, TooltipTrigger } from "./ui/tooltip";
 import { Badge } from "@/components/ui/badge";
@@ -512,7 +513,8 @@ function TaskTreeNode({
               ) : null}
               <div className="min-w-0 flex-1">
                 <div className="flex min-w-0 items-center gap-1.5">
-                  {node.task.priority ? (
+                  {/* PAP-411: priority UI hidden behind SHOW_TASK_PRIORITY_UI. */}
+                  {SHOW_TASK_PRIORITY_UI && node.task.priority ? (
                     <PriorityIcon
                       priority={node.task.priority}
                       className="mt-px"
diff --git a/ui/src/components/IssuesList.test.tsx b/ui/src/components/IssuesList.test.tsx
index 5838bff996..00b9cc7a19 100644
--- a/ui/src/components/IssuesList.test.tsx
+++ b/ui/src/components/IssuesList.test.tsx
@@ -773,6 +773,54 @@ describe("IssuesList", () => {
     });
   });
 
+  it("hides the Priority option from the Sort and Group menus while priority UI is off (PAP-411)", async () => {
+    const { root } = renderWithQueryClient(
+      <IssuesList
+        issues={[createIssue({ id: "issue-1", identifier: "PAP-1", title: "Task one" })]}
+        agents={[]}
+        projects={[]}
+        viewStateKey="paperclip:test-issues"
+        onUpdateIssue={() => undefined}
+      />,
+      container,
+    );
+
+    await waitForAssertion(() => {
+      expect(container.querySelectorAll('[data-testid="issue-row"]').length).toBeGreaterThan(0);
+    });
+
+    const sortButton = Array.from(container.querySelectorAll("button")).find(
+      (button) => button.getAttribute("title") === "Sort",
+    );
+    expect(sortButton).toBeTruthy();
+    act(() => {
+      sortButton?.dispatchEvent(new MouseEvent("click", { bubbles: true }));
+    });
+    await waitForAssertion(() => {
+      const labels = Array.from(document.body.querySelectorAll("button")).map((b) => b.textContent ?? "");
+      // Status sort option renders, but the Priority option is gated off (PAP-411).
+      expect(labels.some((text) => text.includes("Status"))).toBe(true);
+      expect(labels.some((text) => text.includes("Priority"))).toBe(false);
+    });
+
+    const groupButton = Array.from(container.querySelectorAll("button")).find(
+      (button) => button.getAttribute("title") === "Group",
+    );
+    expect(groupButton).toBeTruthy();
+    act(() => {
+      groupButton?.dispatchEvent(new MouseEvent("click", { bubbles: true }));
+    });
+    await waitForAssertion(() => {
+      const labels = Array.from(document.body.querySelectorAll("button")).map((b) => b.textContent ?? "");
+      expect(labels.some((text) => text.includes("Status"))).toBe(true);
+      expect(labels.some((text) => text.includes("Priority"))).toBe(false);
+    });
+
+    act(() => {
+      root.unmount();
+    });
+  });
+
   it("hides the workflow blocker chip when a sub-issue is blocked only by its previous sibling", async () => {
     const firstChild = createIssue({
       id: "issue-first-child",
diff --git a/ui/src/components/IssuesList.tsx b/ui/src/components/IssuesList.tsx
index 2aeb017322..d463691c55 100644
--- a/ui/src/components/IssuesList.tsx
+++ b/ui/src/components/IssuesList.tsx
@@ -46,6 +46,7 @@ import {
   type InboxIssueColumn,
 } from "../lib/inbox";
 import { cn, formatDurationMs, formatTokens } from "../lib/utils";
+import { SHOW_TASK_PRIORITY_UI } from "../lib/ui-flags";
 import { collectSubtreeLiveCounts } from "../lib/liveIssueIds";
 import {
   InboxIssueMetaLeading,
@@ -1827,6 +1828,7 @@ export function IssuesList({
               </PopoverTrigger>
               <PopoverContent align="end" className="w-48 p-0">
                 <div className="p-2 space-y-0.5">
+                  {/* PAP-411: "priority" sort option hidden behind SHOW_TASK_PRIORITY_UI (comparator stays dormant). */}
                   {([
                     ["workflow", "Workflow"],
                     ["status", "Status"],
@@ -1834,7 +1836,9 @@ export function IssuesList({
                     ["title", "Title"],
                     ["created", "Created"],
                     ["updated", "Updated"],
-                  ] as const).map(([field, label]) => (
+                  ] as const)
+                    .filter(([field]) => SHOW_TASK_PRIORITY_UI || field !== "priority")
+                    .map(([field, label]) => (
                     <button
                       key={field}
                       className={`flex items-center justify-between w-full px-2 py-1.5 text-sm rounded-sm ${
@@ -1871,6 +1875,7 @@ export function IssuesList({
               </PopoverTrigger>
               <PopoverContent align="end" className="w-44 p-0">
                 <div className="p-2 space-y-0.5">
+                  {/* PAP-411: "priority" group-by option hidden behind SHOW_TASK_PRIORITY_UI (group logic stays dormant). */}
                   {([
                     ["status", "Status"],
                     ["priority", "Priority"],
@@ -1879,7 +1884,9 @@ export function IssuesList({
                     ["workspace", "Workspace"],
                     ["parent", "Parent Task"],
                     ["none", "None"],
-                  ] as const).map(([value, label]) => (
+                  ] as const)
+                    .filter(([value]) => SHOW_TASK_PRIORITY_UI || value !== "priority")
+                    .map(([value, label]) => (
                     <button
                       key={value}
                       className={`flex items-center justify-between w-full px-2 py-1.5 text-sm rounded-sm ${
diff --git a/ui/src/components/KanbanBoard.tsx b/ui/src/components/KanbanBoard.tsx
index abe0eff2c6..f251729e34 100644
--- a/ui/src/components/KanbanBoard.tsx
+++ b/ui/src/components/KanbanBoard.tsx
@@ -19,6 +19,7 @@ import {
 } from "@dnd-kit/sortable";
 import { StatusIcon } from "./StatusIcon";
 import { PriorityIcon } from "./PriorityIcon";
+import { SHOW_TASK_PRIORITY_UI } from "../lib/ui-flags";
 import { Identity } from "./Identity";
 import type { Issue, IssueStatus } from "@paperclipai/shared";
 import { AlertTriangle } from "lucide-react";
@@ -361,7 +362,8 @@ function KanbanCard({
         </div>
         <p className={`${compact ? "mb-1.5 text-xs" : "mb-2 text-sm"} leading-snug line-clamp-2`}>{issue.title}</p>
         <div className="flex items-center gap-2 min-w-0">
-          <PriorityIcon priority={issue.priority} />
+          {/* PAP-411: priority UI hidden behind SHOW_TASK_PRIORITY_UI. */}
+          {SHOW_TASK_PRIORITY_UI && <PriorityIcon priority={issue.priority} />}
           {issue.assigneeAgentId && (() => {
             const name = agentName(issue.assigneeAgentId);
             return name ? (
diff --git a/ui/src/components/NewIssueDialog.test.tsx b/ui/src/components/NewIssueDialog.test.tsx
index b103b7eedd..5b11679b0f 100644
--- a/ui/src/components/NewIssueDialog.test.tsx
+++ b/ui/src/components/NewIssueDialog.test.tsx
@@ -1111,24 +1111,49 @@ describe("NewIssueDialog", () => {
     act(() => root.unmount());
   });
 
-  it("keeps priority under the mobile overflow menu", async () => {
+  it("hides the priority chip and mobile priority option (PAP-411)", async () => {
     const { root } = renderDialog(container);
     await flush();
 
+    // PAP-411: priority UI is hidden behind SHOW_TASK_PRIORITY_UI (off). Neither the
+    // desktop priority chip nor the mobile overflow priority option should render.
     const priorityChip = container.querySelector('[data-testid="new-issue-priority-chip"]');
-    expect(priorityChip?.className).toContain("hidden");
-    expect(priorityChip?.className).toContain("sm:inline-flex");
+    expect(priorityChip).toBeNull();
 
     const highPriorityOption = container.querySelector('[data-testid="new-issue-more-priority-high"]');
-    expect(highPriorityOption?.textContent).toContain("High");
+    expect(highPriorityOption).toBeNull();
+
+    act(() => root.unmount());
+  });
+
+  it("still submits the default priority when the priority UI is hidden (PAP-411)", async () => {
+    dialogState.newIssueDefaults = {
+      title: "Priority default persists",
+    };
+
+    const { root } = renderDialog(container);
+    await flush();
+
+    const submitButton = Array.from(container.querySelectorAll("button"))
+      .find((button) => button.textContent?.includes("Create Task"));
+    expect(submitButton).not.toBeUndefined();
+    await vi.waitFor(() => {
+      expect(submitButton?.hasAttribute("disabled")).toBe(false);
+    });
 
     await act(async () => {
-      highPriorityOption?.dispatchEvent(new MouseEvent("click", { bubbles: true }));
+      submitButton!.dispatchEvent(new MouseEvent("click", { bubbles: true }));
     });
     await flush();
 
-    const selectedHighPriorityOption = container.querySelector('[data-testid="new-issue-more-priority-high"]');
-    expect(selectedHighPriorityOption?.className).toContain("bg-accent");
+    // PAP-411: the priority control is hidden, but the data-model default must survive.
+    expect(mockIssuesApi.create).toHaveBeenCalledWith(
+      "company-1",
+      expect.objectContaining({
+        title: "Priority default persists",
+        priority: "medium",
+      }),
+    );
 
     act(() => root.unmount());
   });
diff --git a/ui/src/components/NewIssueDialog.tsx b/ui/src/components/NewIssueDialog.tsx
index cfe630b871..35d1f627ba 100644
--- a/ui/src/components/NewIssueDialog.tsx
+++ b/ui/src/components/NewIssueDialog.tsx
@@ -73,6 +73,7 @@ import { Textarea } from "@/components/ui/textarea";
 import { cn } from "../lib/utils";
 import { extractProviderIdWithFallback } from "../lib/model-utils";
 import { issueStatusText, issueStatusTextDefault, priorityColor, priorityColorDefault } from "../lib/status-colors";
+import { SHOW_TASK_PRIORITY_UI } from "../lib/ui-flags";
 import { MarkdownEditor, type MarkdownEditorRef, type MentionOption } from "./MarkdownEditor";
 import { AgentIcon } from "./AgentIconPicker";
 import { InlineEntitySelector, type InlineEntityOption } from "./InlineEntitySelector";
@@ -2072,7 +2073,8 @@ export function NewIssueDialog() {
             </PopoverContent>
           </Popover>
 
-          {/* Priority chip */}
+          {/* Priority chip — PAP-411: hidden behind SHOW_TASK_PRIORITY_UI. */}
+          {SHOW_TASK_PRIORITY_UI && (
           <Popover open={priorityOpen} onOpenChange={setPriorityOpen}>
             <PopoverTrigger asChild>
               <button
@@ -2109,6 +2111,7 @@ export function NewIssueDialog() {
               ))}
             </PopoverContent>
           </Popover>
+          )}
 
           {/* Labels chip — disabled, not wired up yet */}
           {/* <button className="inline-flex items-center gap-1.5 rounded-md border border-border px-2 py-1 text-xs hover:bg-accent/50 transition-colors text-muted-foreground">
@@ -2187,6 +2190,8 @@ export function NewIssueDialog() {
               </button>
             </PopoverTrigger>
             <PopoverContent className="w-44 p-1" align="start" data-testid="new-issue-more-menu">
+              {/* PAP-411: mobile priority section hidden behind SHOW_TASK_PRIORITY_UI. */}
+              {SHOW_TASK_PRIORITY_UI && (
               <div className="sm:hidden">
                 <div className="px-2 py-1 text-(length:--text-nano) font-medium uppercase text-muted-foreground">
                   Priority
@@ -2211,6 +2216,7 @@ export function NewIssueDialog() {
                 ))}
                 <div className="my-1 border-t border-border" />
               </div>
+              )}
               <button className="flex items-center gap-2 w-full px-2 py-1.5 text-xs rounded hover:bg-accent/50 text-muted-foreground">
                 <Calendar className="h-3 w-3" />
                 Start date
diff --git a/ui/src/components/issue-properties/IssueProperties.tsx b/ui/src/components/issue-properties/IssueProperties.tsx
index 45a115beb7..48112bd8f3 100644
--- a/ui/src/components/issue-properties/IssueProperties.tsx
+++ b/ui/src/components/issue-properties/IssueProperties.tsx
@@ -44,6 +44,7 @@ import { useRetryNowMutation } from "../../hooks/useRetryNowMutation";
 import { RetryErrorBand } from "../IssueScheduledRetryCard";
 import { StatusIcon } from "../StatusIcon";
 import { PriorityIcon } from "../PriorityIcon";
+import { SHOW_TASK_PRIORITY_UI } from "../../lib/ui-flags";
 import { Identity } from "../Identity";
 import { IssueReferencePill } from "../IssueReferencePill";
 import { formatDate, formatDateTime, cn, projectUrl } from "../../lib/utils";
@@ -2026,13 +2027,16 @@ export function IssueProperties({
           />
         </PropertyRow>
 
-        <PropertyRow label="Priority">
-          <PriorityIcon
-            priority={issue.priority}
-            onChange={(priority) => onUpdate({ priority })}
-            showLabel
-          />
-        </PropertyRow>
+        {/* PAP-411: priority UI is hidden behind SHOW_TASK_PRIORITY_UI. Revive by flipping the flag. */}
+        {SHOW_TASK_PRIORITY_UI && (
+          <PropertyRow label="Priority">
+            <PriorityIcon
+              priority={issue.priority}
+              onChange={(priority) => onUpdate({ priority })}
+              showLabel
+            />
+          </PropertyRow>
+        )}
 
         <PropertyPicker
           inline={inline}
diff --git a/ui/src/components/search/SearchFilterBar.tsx b/ui/src/components/search/SearchFilterBar.tsx
index 3c75fb5c0b..9dfd16631a 100644
--- a/ui/src/components/search/SearchFilterBar.tsx
+++ b/ui/src/components/search/SearchFilterBar.tsx
@@ -10,6 +10,7 @@ import {
 } from "@paperclipai/shared";
 import { StatusIcon } from "@/components/StatusIcon";
 import { PriorityIcon } from "@/components/PriorityIcon";
+import { SHOW_TASK_PRIORITY_UI } from "@/lib/ui-flags";
 import { SearchFilterMenu, type FilterMenuOption } from "./SearchFilterMenu";
 import { SearchSortMenu } from "./SearchSortMenu";
 import {
@@ -197,6 +198,8 @@ export function SearchFilterBar({
         searchPlaceholder="Search labels…"
         emptyMessage="No labels"
       />
+      {/* PAP-411: Priority filter menu hidden behind SHOW_TASK_PRIORITY_UI (search DSL stays intact). */}
+      {SHOW_TASK_PRIORITY_UI && (
       <SearchFilterMenu
         label="Priority"
         multi
@@ -205,6 +208,7 @@ export function SearchFilterBar({
         onToggle={(value) => toggleMulti("priority", value)}
         onClear={() => onChange({ ...filters, priority: [] })}
       />
+      )}
       <SearchFilterMenu
         label="Updated"
         options={options.updated}
diff --git a/ui/src/components/search/SearchFilterSheet.tsx b/ui/src/components/search/SearchFilterSheet.tsx
index b1b3946a61..602bd1ff24 100644
--- a/ui/src/components/search/SearchFilterSheet.tsx
+++ b/ui/src/components/search/SearchFilterSheet.tsx
@@ -11,6 +11,7 @@ import {
   SheetTitle,
 } from "@/components/ui/sheet";
 import { cn } from "@/lib/utils";
+import { SHOW_TASK_PRIORITY_UI } from "@/lib/ui-flags";
 import {
   applyAssigneeToken,
   assigneeToken,
@@ -154,12 +155,15 @@ export function SearchFilterSheet({
             selected={draft.status ?? []}
             onToggle={(value) => toggleMulti("status", value)}
           />
+          {/* PAP-411: Priority filter group hidden behind SHOW_TASK_PRIORITY_UI (search DSL stays intact). */}
+          {SHOW_TASK_PRIORITY_UI && (
           <ChipToggleGroup
             title="Priority"
             options={options.priority}
             selected={draft.priority ?? []}
             onToggle={(value) => toggleMulti("priority", value)}
           />
+          )}
           <ChipToggleGroup
             title="Assignee"
             options={options.assignee}
diff --git a/ui/src/lib/search-filters.ts b/ui/src/lib/search-filters.ts
index b08302ba14..f0fb139cc3 100644
--- a/ui/src/lib/search-filters.ts
+++ b/ui/src/lib/search-filters.ts
@@ -136,6 +136,11 @@ export function buildFilterChips(filters: SearchFilters, lookups: FilterChipLook
       },
     });
   }
+  // PAP-411: priority controls are hidden from the UI, but the priority filter
+  // DSL (`priority:high`) stays functional at the data layer per board decision.
+  // A priority filter can therefore still enter the query via URL round-trip or
+  // typed DSL, so we always render a removable chip for it — otherwise a restored
+  // priority filter would silently narrow results with no way to see or clear it.
   for (const priority of filters.priority ?? []) {
     chips.push({
       id: `priority:${priority}`,
diff --git a/ui/src/lib/ui-flags.ts b/ui/src/lib/ui-flags.ts
new file mode 100644
index 0000000000..8f5c4f80d0
--- /dev/null
+++ b/ui/src/lib/ui-flags.ts
@@ -0,0 +1,22 @@
+/**
+ * Product UI feature flags.
+ *
+ * These are compile-time constants that gate presentation-only surfaces. They
+ * deliberately do NOT touch the data model, API, validation, or filter DSL — a
+ * gated feature stays fully functional at the data layer and can be revived by
+ * flipping the flag back to `true`.
+ */
+
+/**
+ * Controls whether task/issue **priority** indicators and controls are shown in
+ * the product UI.
+ *
+ * Set to `false` for PAP-411 ("remove task priority level from the UI"). The
+ * priority data model, API params, Zod validation (including the `"medium"`
+ * default), and filter DSL are intentionally left intact so priority can be
+ * revived by flipping this single boolean back to `true`.
+ *
+ * Typed as `boolean` (not the literal `false`) on purpose: this keeps
+ * TypeScript and lint from flagging the gated branches as unreachable/dead code.
+ */
+export const SHOW_TASK_PRIORITY_UI: boolean = false;
diff --git a/ui/src/pages/AgentDetail.tsx b/ui/src/pages/AgentDetail.tsx
index 5a7202b908..4f7a21986c 100644
--- a/ui/src/pages/AgentDetail.tsx
+++ b/ui/src/pages/AgentDetail.tsx
@@ -14,6 +14,7 @@ import { heartbeatsApi } from "../api/heartbeats";
 import { instanceSettingsApi } from "../api/instanceSettings";
 import { ApiError } from "../api/client";
 import { ChartCard, RunActivityChart, PriorityChart, IssueStatusChart, SuccessRateChart } from "../components/ActivityCharts";
+import { SHOW_TASK_PRIORITY_UI } from "../lib/ui-flags";
 import { activityApi } from "../api/activity";
 import { accessApi } from "../api/access";
 import { issuesApi } from "../api/issues";
@@ -1542,9 +1543,12 @@ function AgentOverview({
         <ChartCard title="Run Activity" subtitle="Last 14 days">
           <RunActivityChart runs={runs} />
         </ChartCard>
-        <ChartCard title="Tasks by Priority" subtitle="Last 14 days">
-          <PriorityChart issues={assignedIssues} />
-        </ChartCard>
+        {/* PAP-411: "Tasks by Priority" chart hidden behind SHOW_TASK_PRIORITY_UI. */}
+        {SHOW_TASK_PRIORITY_UI && (
+          <ChartCard title="Tasks by Priority" subtitle="Last 14 days">
+            <PriorityChart issues={assignedIssues} />
+          </ChartCard>
+        )}
         <ChartCard title="Tasks by Status" subtitle="Last 14 days">
           <IssueStatusChart issues={assignedIssues} />
         </ChartCard>
diff --git a/ui/src/pages/Dashboard.tsx b/ui/src/pages/Dashboard.tsx
index 5146c19191..f3ff724def 100644
--- a/ui/src/pages/Dashboard.tsx
+++ b/ui/src/pages/Dashboard.tsx
@@ -21,6 +21,7 @@ import { ActivityRow } from "../components/ActivityRow";
 import { Identity } from "../components/Identity";
 import { timeAgo } from "../lib/timeAgo";
 import { cn, formatCents } from "../lib/utils";
+import { SHOW_TASK_PRIORITY_UI } from "../lib/ui-flags";
 import { Bot, CircleDot, DollarSign, ShieldCheck, LayoutDashboard, PauseCircle } from "lucide-react";
 import { ActiveAgentsPanel } from "../components/ActiveAgentsPanel";
 import { ChartCard, RunActivityChart, PriorityChart, IssueStatusChart, SuccessRateChart } from "../components/ActivityCharts";
@@ -316,9 +317,12 @@ export function Dashboard() {
             <ChartCard title="Run Activity" subtitle="Last 14 days">
               <RunActivityChart activity={data.runActivity} />
             </ChartCard>
-            <ChartCard title="Tasks by Priority" subtitle="Last 14 days">
-              <PriorityChart issues={issues ?? []} />
-            </ChartCard>
+            {/* PAP-411: "Tasks by Priority" chart hidden behind SHOW_TASK_PRIORITY_UI. */}
+            {SHOW_TASK_PRIORITY_UI && (
+              <ChartCard title="Tasks by Priority" subtitle="Last 14 days">
+                <PriorityChart issues={issues ?? []} />
+              </ChartCard>
+            )}
             <ChartCard title="Tasks by Status" subtitle="Last 14 days">
               <IssueStatusChart issues={issues ?? []} />
             </ChartCard>
diff --git a/ui/src/pages/DesignGuide.tsx b/ui/src/pages/DesignGuide.tsx
index f54ae6c2cc..d62334bef0 100644
--- a/ui/src/pages/DesignGuide.tsx
+++ b/ui/src/pages/DesignGuide.tsx
@@ -125,6 +125,7 @@ import { StatusIcon } from "@/components/StatusIcon";
 import { EnforcementBanner } from "@/components/EnforcementBanner";
 import { ActionCard, ActionCardMobile, BindingsTable } from "@/components/actions/ActionCard";
 import { PriorityIcon } from "@/components/PriorityIcon";
+import { SHOW_TASK_PRIORITY_UI } from "@/lib/ui-flags";
 import { agentStatusDot, agentStatusDotDefault } from "@/lib/status-colors";
 import { EntityRow } from "@/components/EntityRow";
 import { EmptyState } from "@/components/EmptyState";
@@ -384,7 +385,10 @@ export function DesignGuide() {
   );
   const [filters, setFilters] = useState<FilterValue[]>([
     { key: "status", label: "Status", value: "Active" },
-    { key: "priority", label: "Priority", value: "High" },
+    // PAP-411: priority filter demo row suppressed while SHOW_TASK_PRIORITY_UI is off.
+    ...(SHOW_TASK_PRIORITY_UI
+      ? [{ key: "priority", label: "Priority", value: "High" } as FilterValue]
+      : []),
   ]);
   const [allowExternal, setAllowExternal] = useState(false);
   const [allowUnpinned, setAllowUnpinned] = useState(false);
@@ -637,6 +641,8 @@ export function DesignGuide() {
           </div>
         </SubSection>
 
+        {/* PAP-411: PriorityIcon showcase gated behind SHOW_TASK_PRIORITY_UI per board decision. */}
+        {SHOW_TASK_PRIORITY_UI && (
         <SubSection title="PriorityIcon (interactive)">
           <div className="flex items-center gap-3 flex-wrap">
             {["critical", "high", "medium", "low"].map((p) => (
@@ -651,6 +657,7 @@ export function DesignGuide() {
             <span className="text-sm">Click the icon to change (current: {priority})</span>
           </div>
         </SubSection>
+        )}
 
         <SubSection title="Agent status dots">
           <div className="flex items-center gap-4 flex-wrap">
@@ -1123,7 +1130,8 @@ export function DesignGuide() {
             leading={
               <>
                 <StatusIcon status="in_progress" />
-                <PriorityIcon priority="high" />
+                {/* PAP-411: PriorityIcon hidden behind SHOW_TASK_PRIORITY_UI. */}
+                {SHOW_TASK_PRIORITY_UI && <PriorityIcon priority="high" />}
               </>
             }
             identifier="PAP-001"
@@ -1136,7 +1144,7 @@ export function DesignGuide() {
             leading={
               <>
                 <StatusIcon status="done" />
-                <PriorityIcon priority="medium" />
+                {SHOW_TASK_PRIORITY_UI && <PriorityIcon priority="medium" />}
               </>
             }
             identifier="PAP-002"
@@ -1149,7 +1157,7 @@ export function DesignGuide() {
             leading={
               <>
                 <StatusIcon status="todo" />
-                <PriorityIcon priority="low" />
+                {SHOW_TASK_PRIORITY_UI && <PriorityIcon priority="low" />}
               </>
             }
             identifier="PAP-003"
@@ -1161,7 +1169,7 @@ export function DesignGuide() {
             leading={
               <>
                 <StatusIcon status="blocked" />
-                <PriorityIcon priority="critical" />
+                {SHOW_TASK_PRIORITY_UI && <PriorityIcon priority="critical" />}
               </>
             }
             identifier="PAP-004"
@@ -1249,7 +1257,10 @@ export function DesignGuide() {
             onClick={() =>
               setFilters([
                 { key: "status", label: "Status", value: "Active" },
-                { key: "priority", label: "Priority", value: "High" },
+                // PAP-411: priority filter demo row suppressed while SHOW_TASK_PRIORITY_UI is off.
+                ...(SHOW_TASK_PRIORITY_UI
+                  ? [{ key: "priority", label: "Priority", value: "High" } as FilterValue]
+                  : []),
               ])
             }
           >
@@ -1429,10 +1440,13 @@ export function DesignGuide() {
             <span className="text-xs text-muted-foreground">Status</span>
             <StatusBadge status="active" />
           </div>
-          <div className="flex items-center justify-between py-1.5">
-            <span className="text-xs text-muted-foreground">Priority</span>
-            <PriorityIcon priority="high" />
-          </div>
+          {/* PAP-411: priority metadata row hidden behind SHOW_TASK_PRIORITY_UI. */}
+          {SHOW_TASK_PRIORITY_UI && (
+            <div className="flex items-center justify-between py-1.5">
+              <span className="text-xs text-muted-foreground">Priority</span>
+              <PriorityIcon priority="high" />
+            </div>
+          )}
           <div className="flex items-center justify-between py-1.5">
             <span className="text-xs text-muted-foreground">Responsible</span>
             <div className="flex items-center gap-1.5">
@@ -1500,14 +1514,15 @@ export function DesignGuide() {
             <span className="text-xs text-muted-foreground ml-1">2</span>
           </div>
           <div className="border border-border rounded-b-md">
+            {/* PAP-411: leading PriorityIcon hidden behind SHOW_TASK_PRIORITY_UI. */}
             <EntityRow
-              leading={<PriorityIcon priority="high" />}
+              leading={SHOW_TASK_PRIORITY_UI ? <PriorityIcon priority="high" /> : undefined}
               identifier="PAP-101"
               title="Build agent heartbeat system"
               onClick={() => {}}
             />
             <EntityRow
-              leading={<PriorityIcon priority="medium" />}
+              leading={SHOW_TASK_PRIORITY_UI ? <PriorityIcon priority="medium" /> : undefined}
               identifier="PAP-102"
               title="Add cost tracking dashboard"
               onClick={() => {}}
diff --git a/ui/src/pages/IssueDetail.test.tsx b/ui/src/pages/IssueDetail.test.tsx
index fa0d1b5c4a..8ef40448e7 100644
--- a/ui/src/pages/IssueDetail.test.tsx
+++ b/ui/src/pages/IssueDetail.test.tsx
@@ -1108,7 +1108,7 @@ describe("IssueDetail", () => {
     expect(mockDecisionsApi.list).not.toHaveBeenCalled();
   });
 
-  it("updates status and priority from the task header controls", async () => {
+  it("updates status from the task header control and hides the priority control (PAP-411)", async () => {
     const issue = createIssue({ status: "todo", priority: "medium" });
     mockIssuesApi.get.mockResolvedValue(issue);
     mockIssuesApi.update.mockImplementation(async (_issueId: string, data: Record<string, unknown>) => ({
@@ -1133,7 +1133,9 @@ describe("IssueDetail", () => {
       'button[aria-label="Change priority (current: medium)"]',
     );
     expect(statusButton).not.toBeNull();
-    expect(priorityButton).not.toBeNull();
+    // PAP-411: priority UI is hidden behind SHOW_TASK_PRIORITY_UI (off), so the header
+    // priority control must not render.
+    expect(priorityButton).toBeNull();
 
     await act(async () => {
       statusButton!.dispatchEvent(new MouseEvent("click", { bubbles: true, cancelable: true }));
@@ -1141,13 +1143,10 @@ describe("IssueDetail", () => {
     await waitForAssertion(() => {
       expect(mockIssuesApi.update).toHaveBeenCalledWith(issue.identifier, { status: "done" });
     });
-
-    await act(async () => {
-      priorityButton!.dispatchEvent(new MouseEvent("click", { bubbles: true, cancelable: true }));
-    });
-    await waitForAssertion(() => {
-      expect(mockIssuesApi.update).toHaveBeenCalledWith(issue.identifier, { priority: "high" });
-    });
+    expect(mockIssuesApi.update).not.toHaveBeenCalledWith(
+      issue.identifier,
+      expect.objectContaining({ priority: expect.anything() }),
+    );
 
     mockIssuesApi.update.mockReset();
   });
diff --git a/ui/src/pages/IssueDetail.tsx b/ui/src/pages/IssueDetail.tsx
index 483fb2860d..1c632986e4 100644
--- a/ui/src/pages/IssueDetail.tsx
+++ b/ui/src/pages/IssueDetail.tsx
@@ -135,6 +135,7 @@ import { ArtifactFileChip } from "../components/ArtifactFileChip";
 import { ScrollToBottom } from "../components/ScrollToBottom";
 import { StatusIcon } from "../components/StatusIcon";
 import { PriorityIcon } from "../components/PriorityIcon";
+import { SHOW_TASK_PRIORITY_UI } from "../lib/ui-flags";
 import { ProductivityReviewBadge } from "../components/ProductivityReviewBadge";
 import { Identity } from "../components/Identity";
 import { PluginSlotMount, PluginSlotOutlet, usePluginSlots } from "@/plugins/slots";
@@ -706,7 +707,8 @@ function IssueDetailLoadingState({
           {headerSeed ? (
             <>
               <StatusIcon status={headerSeed.status} blockerAttention={headerSeed.blockerAttention} />
-              <PriorityIcon priority={headerSeed.priority} />
+              {/* PAP-411: priority UI hidden behind SHOW_TASK_PRIORITY_UI. */}
+              {SHOW_TASK_PRIORITY_UI && <PriorityIcon priority={headerSeed.priority} />}
               {identifier ? (
                 <span className="text-sm font-mono text-muted-foreground shrink-0">{identifier}</span>
               ) : null}
@@ -4195,10 +4197,13 @@ export function IssueDetail() {
             blockerAttention={issue.blockerAttention}
             onChange={(status) => updateIssue.mutate({ status })}
           />
-          <PriorityIcon
-            priority={issue.priority}
-            onChange={(priority) => updateIssue.mutate({ priority })}
-          />
+          {/* PAP-411: priority UI hidden behind SHOW_TASK_PRIORITY_UI. */}
+          {SHOW_TASK_PRIORITY_UI && (
+            <PriorityIcon
+              priority={issue.priority}
+              onChange={(priority) => updateIssue.mutate({ priority })}
+            />
+          )}
           <span className="text-sm font-mono text-muted-foreground shrink-0">{issue.identifier ?? issue.id.slice(0, 8)}</span>
 
           {hasLiveRuns && (