diff --git a/.github/workflows/ax.yml b/.github/workflows/ax.yml
index 00d1401ea5..b853ae60ee 100644
--- a/.github/workflows/ax.yml
+++ b/.github/workflows/ax.yml
@@ -123,8 +123,9 @@ jobs:
       matrix:
         config:
           #@note llvm10 never got its own brew formula...
-          - { runner: 'macos-latest', cxx: 'clang++', build: 'Release', llvm: '12' }
-          - { runner: 'macos-latest', cxx: 'clang++', build: 'Release', llvm: '13' }
+          # Last macos runner befor M1 (macos-14)
+          - { runner: 'macos-13', cxx: 'clang++', build: 'Release', llvm: '12' }
+          - { runner: 'macos-13', cxx: 'clang++', build: 'Release', llvm: '13' }
       fail-fast: false
     steps:
       - uses: actions/checkout@v3
diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 682cc1cb03..5514f2d856 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -186,7 +186,7 @@ jobs:
       github.event_name != 'workflow_dispatch' ||
       github.event.inputs.type == 'all' ||
       github.event.inputs.type == 'mac'
-    runs-on: macos-latest
+    runs-on: macos-13 # Last macos runner befor M1 (macos-14)
     env:
       CXX: clang++
     steps:
diff --git a/.github/workflows/weekly.yml b/.github/workflows/weekly.yml
index 6394fd8ac0..71e36f7bf3 100644
--- a/.github/workflows/weekly.yml
+++ b/.github/workflows/weekly.yml
@@ -111,6 +111,8 @@ jobs:
       (github.event_name != 'workflow_dispatch' ||
        github.event.inputs.type == 'all' ||
        github.event.inputs.type == 'houdini')
+    # Note that macos-14 (current macos-latest) switches to M1. We could instead test
+    # the arm build here instead of the x86 one.
     runs-on: macos-latest
     name: macos-houdini-20
     env:
@@ -291,7 +293,7 @@ jobs:
       github.event_name != 'workflow_dispatch' ||
       github.event.inputs.type == 'all' ||
       github.event.inputs.type == 'ax'
-    runs-on: macos-latest
+    runs-on: macos-13
     name: macos-cxx:${{ matrix.config.cxx }}-llvm:${{ matrix.config.llvm }}-${{ matrix.config.build }}
     env:
       CXX: ${{ matrix.config.cxx }}