diff --git a/.github/workflows/tests-macos.yml b/.github/workflows/tests-macos.yml
index 5f78a72ab..312c2996a 100644
--- a/.github/workflows/tests-macos.yml
+++ b/.github/workflows/tests-macos.yml
@@ -17,6 +17,7 @@ jobs:
       PYTEST_ADDOPTS: -n auto
       DELTA_API_KEY: ${{ secrets.DELTA_API_KEY }}
       DELTA_REPO_ID: ${{ secrets.DELTA_REPO_ID }}
+      DELTA_BRANCH: master
     strategy:
       fail-fast: false
       matrix:
diff --git a/.github/workflows/tests-ubuntu.yml b/.github/workflows/tests-ubuntu.yml
index f5f02710d..36d9139cc 100644
--- a/.github/workflows/tests-ubuntu.yml
+++ b/.github/workflows/tests-ubuntu.yml
@@ -134,6 +134,7 @@ jobs:
       PYTEST_ADDOPTS: -n auto
       DELTA_API_KEY: ${{ secrets.DELTA_API_KEY }}
       DELTA_REPO_ID: ${{ secrets.DELTA_REPO_ID }}
+      DELTA_BRANCH: master
     strategy:
       fail-fast: false
       matrix:
diff --git a/.github/workflows/tests-windows.yml b/.github/workflows/tests-windows.yml
index 4eb03920b..30409a0aa 100644
--- a/.github/workflows/tests-windows.yml
+++ b/.github/workflows/tests-windows.yml
@@ -17,6 +17,7 @@ jobs:
       PYTEST_ADDOPTS: -n auto
       DELTA_API_KEY: ${{ secrets.DELTA_API_KEY }}
       DELTA_REPO_ID: ${{ secrets.DELTA_REPO_ID }}
+      DELTA_BRANCH: master
     strategy:
       fail-fast: false
       matrix: