diff --git a/.github/workflows/build-timestamped-master.yml b/.github/workflows/build-timestamped-master.yml
index 445f7992..d37f00fc 100644
--- a/.github/workflows/build-timestamped-master.yml
+++ b/.github/workflows/build-timestamped-master.yml
@@ -5,6 +5,7 @@ on:
   push:
     branches:
       - main
+      - 2201.[0-9]+.x
     paths-ignore:
      - '*.md'
      - 'docs/**'
diff --git a/.github/workflows/pull-request.yml b/.github/workflows/pull-request.yml
index bf9f80ad..3b91178b 100644
--- a/.github/workflows/pull-request.yml
+++ b/.github/workflows/pull-request.yml
@@ -1,6 +1,10 @@
 name: PR build
 
-on: [pull_request]
+on:
+  pull_request:
+    branches:
+      - master
+      - 2201.[0-9]+.x
 
 jobs:
   ubuntu-build: