diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index a625670..8dda63e 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -122,6 +122,9 @@ jobs:
           - toolset: clang
             cxxstd: "03,11,14,17,2a"
             os: macos-11
+          - toolset: clang
+            cxxstd: "03,11,14,17,20,2b"
+            os: macos-12
 
     runs-on: ${{matrix.os}}