diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 42122ce..5d4c59b 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -18,7 +18,7 @@ jobs:
         rust:
           - stable
           - beta
-          - 1.65.0  # MSRV from Cargo.toml
+          - 1.66.0  # MSRV from Cargo.toml
     steps:
     - uses: actions/checkout@v4
     - uses: dtolnay/rust-toolchain@master
@@ -26,7 +26,7 @@ jobs:
         toolchain: ${{ matrix.rust }}
     - uses: Swatinem/rust-cache@v2
     - name: Use MSRV lockfile for minimum version testing
-      if: matrix.rust == '1.65.0'
+      if: matrix.rust == '1.66.0'
       run: cp Cargo.lock.msrv Cargo.lock
     - name: Run tests
       run: cargo test --verbose