diff --git a/.github/workflows/cost-model-bench.yml b/.github/workflows/cost-model-bench.yml
index c7e918959b4..5b92e4896ab 100644
--- a/.github/workflows/cost-model-bench.yml
+++ b/.github/workflows/cost-model-bench.yml
@@ -19,7 +19,7 @@ jobs:
 
     steps:
       - uses: actions/checkout@v4
-      - uses: cachix/install-nix-action@v26
+      - uses: cachix/install-nix-action@V27
         with:
           extra_nix_config: |
             experimental-features = nix-command flakes
diff --git a/.github/workflows/longitudinal-benchmark.yml b/.github/workflows/longitudinal-benchmark.yml
index c61b426597c..0b704711783 100644
--- a/.github/workflows/longitudinal-benchmark.yml
+++ b/.github/workflows/longitudinal-benchmark.yml
@@ -25,7 +25,7 @@ jobs:
     runs-on: [self-hosted, plutus-benchmark]
     steps:
       - uses: actions/checkout@v4
-      - uses: cachix/install-nix-action@v26
+      - uses: cachix/install-nix-action@V27
         with:
           nix_path: nixpkgs=channel:nixos-unstable
 
diff --git a/.github/workflows/nightly.yml b/.github/workflows/nightly.yml
index aaad383ab57..c7f14577e29 100644
--- a/.github/workflows/nightly.yml
+++ b/.github/workflows/nightly.yml
@@ -13,7 +13,7 @@ jobs:
         uses: actions/checkout@v4
 
       - name: Quick Install Nix
-        uses: cachix/install-nix-action@v26
+        uses: cachix/install-nix-action@V27
         with:
           extra_nix_config: |
             experimental-features = nix-command flakes
diff --git a/.github/workflows/script-evaluation-test.yml b/.github/workflows/script-evaluation-test.yml
index e2607454d59..fac93ebaf7b 100644
--- a/.github/workflows/script-evaluation-test.yml
+++ b/.github/workflows/script-evaluation-test.yml
@@ -19,7 +19,7 @@ jobs:
         uses: actions/checkout@v4
 
       - name: Quick Install Nix
-        uses: cachix/install-nix-action@v26
+        uses: cachix/install-nix-action@V27
         with:
           extra_nix_config: |
             experimental-features = nix-command flakes