diff --git a/.github/workflows/prod-build.yml b/.github/workflows/prod-build.yml
index faf02fdee7b6..c69e4e379b7a 100644
--- a/.github/workflows/prod-build.yml
+++ b/.github/workflows/prod-build.yml
@@ -51,6 +51,9 @@ jobs:
   build:
     runs-on: ubuntu-latest
 
+    # Only run the scheduled workflows on the main repo.
+    if: github.repository == 'mdn/yari'
+
     steps:
       - uses: actions/checkout@v2
 
diff --git a/.github/workflows/stage-build.yml b/.github/workflows/stage-build.yml
index 527987bd1184..29b5790b82f8 100644
--- a/.github/workflows/stage-build.yml
+++ b/.github/workflows/stage-build.yml
@@ -51,6 +51,9 @@ jobs:
   build:
     runs-on: ubuntu-latest
 
+    # Only run the scheduled workflows on the main repo.
+    if: github.repository == 'mdn/yari'
+
     steps:
       - uses: actions/checkout@v2