diff --git a/.github/workflows/cancel-merged-pr-tests.yml b/.github/workflows/cancel-merged-pr-tests.yml
new file mode 100644
index 0000000000..e5fd8cf5f8
--- /dev/null
+++ b/.github/workflows/cancel-merged-pr-tests.yml
@@ -0,0 +1,30 @@
+name: Cancel Merged PR Tests
+
+on:
+  pull_request:
+    branches: [main]
+    types: [closed]
+
+permissions:
+  contents: read
+
+jobs:
+  gateway-tests:
+    name: Cancel PR Test (SMG)
+    if: github.event.pull_request.merged == true
+    runs-on: ubuntu-latest
+    concurrency:
+      group: gateway-tests-pr-${{ github.event.pull_request.number }}
+      cancel-in-progress: true
+    steps:
+      - run: echo "Cancelling in-progress PR Test (SMG) runs for merged PR #${{ github.event.pull_request.number }}."
+
+  mlx-tests:
+    name: Cancel PR Test (MLX)
+    if: github.event.pull_request.merged == true
+    runs-on: ubuntu-latest
+    concurrency:
+      group: mlx-tests-pr-${{ github.event.pull_request.number }}
+      cancel-in-progress: true
+    steps:
+      - run: echo "Cancelling in-progress PR Test (MLX) runs for merged PR #${{ github.event.pull_request.number }}."
diff --git a/.github/workflows/pr-test-mlx.yml b/.github/workflows/pr-test-mlx.yml
index a5fee94458..d4146d4d14 100644
--- a/.github/workflows/pr-test-mlx.yml
+++ b/.github/workflows/pr-test-mlx.yml
@@ -36,8 +36,8 @@ permissions:
   contents: read
 
 concurrency:
-  group: mlx-tests-${{ github.ref }}
-  cancel-in-progress: ${{ github.event_name == 'pull_request' }}
+  group: mlx-tests-${{ github.event_name == 'pull_request' && format('pr-{0}', github.event.pull_request.number) || github.ref_name }}
+  cancel-in-progress: true
 
 jobs:
   e2e-mlx:
diff --git a/.github/workflows/pr-test-rust.yml b/.github/workflows/pr-test-rust.yml
index f37861637e..f0a3a2d86a 100644
--- a/.github/workflows/pr-test-rust.yml
+++ b/.github/workflows/pr-test-rust.yml
@@ -20,8 +20,8 @@ permissions:
   contents: read
 
 concurrency:
-  group: gateway-tests-${{ github.ref }}
-  cancel-in-progress: ${{ github.event_name == 'pull_request' }}
+  group: gateway-tests-${{ github.event_name == 'pull_request' && format('pr-{0}', github.event.pull_request.number) || github.ref_name }}
+  cancel-in-progress: true
 
 env:
   RUSTC_WRAPPER: sccache