diff --git a/.github/workflows/formal.yml b/.github/workflows/formal.yml
index ac1ce2f0..0ae2e0b4 100644
--- a/.github/workflows/formal.yml
+++ b/.github/workflows/formal.yml
@@ -22,7 +22,7 @@ jobs:
       - name: Setup Mill
         uses: jodersky/setup-mill@v0.2.3
         with:
-          mill-version: 0.9.7
+          mill-version: 0.11.5
       - name: Cache Scala
         uses: coursier/cache-action@v5
       - name: mill Test