diff --git a/README.md b/README.md
index 6d150b4..8cfe0e2 100644
--- a/README.md
+++ b/README.md
@@ -53,7 +53,7 @@ jobs:
       contents: read
     steps:
       - uses: actions/checkout@v6.0.2
-      - uses: DeterminateSystems/determinate-nix-action@main # or v3.16.0 to pin to a release
+      - uses: DeterminateSystems/determinate-nix-action@main # or v3.16.3 to pin to a release
       - run: nix build .
 ```
 
@@ -67,10 +67,10 @@ jobs:
 Unlike `DeterminateSystems/nix-installer-action`, we fully support explicit version pinning for maximum consistency.
 This Action is **automatically tagged** for every Determinate Nix release, giving you complete control over your CI environment:
 
-📍 Pinning to `DeterminateSystems/determinate-nix-action@v3.16.0` guarantees:
+📍 Pinning to `DeterminateSystems/determinate-nix-action@v3.16.3` guarantees:
 
 - Same `nix-installer-action` revision every time
-- Consistent Determinate Nix v3.16.0 installation
+- Consistent Determinate Nix v3.16.3 installation
 - Reproducible CI workflows, even years later
 
 ✨ Using `@main` instead? You'll:
@@ -113,7 +113,7 @@ updates:
 | `source-branch`         | The branch of `nix-installer` to use (conflicts with `source-tag`, `source-revision`, `source-pr`)                                                                                                                                                                             |          |                            |
 | `source-pr`             | The PR of `nix-installer` to use (conflicts with `source-tag`, `source-revision`, `source-branch`)                                                                                                                                                                             |          |                            |
 | `source-revision`       | The revision of `nix-installer` to use (conflicts with `source-tag`, `source-branch`, `source-pr`)                                                                                                                                                                             |          |                            |
-| `source-tag`            | The tag of `nix-installer` to use (conflicts with `source-revision`, `source-branch`, `source-pr`)                                                                                                                                                                             |          | `v3.16.0`                  |
+| `source-tag`            | The tag of `nix-installer` to use (conflicts with `source-revision`, `source-branch`, `source-pr`)                                                                                                                                                                             |          | `v3.16.3`                  |
 | `source-url`            | A URL pointing to a `nix-installer` executable                                                                                                                                                                                                                                 |          |                            |
 | `backtrace`             | The setting for `RUST_BACKTRACE` (see https://doc.rust-lang.org/std/backtrace/index.html#environment-variables)                                                                                                                                                                |          |                            |
 | `diagnostic-endpoint`   | Diagnostic endpoint url where the installer sends data to. To disable set this to an empty string.                                                                                                                                                                             |          | `-`                        |
diff --git a/action.yml b/action.yml
index aeec5d5..4670ae4 100644
--- a/action.yml
+++ b/action.yml
@@ -72,7 +72,7 @@
         "source-tag": {
             "description": "The tag of `nix-installer` to use (conflicts with `source-revision`, `source-branch`, `source-pr`)",
             "required": false,
-            "default": "v3.16.0"
+            "default": "v3.16.3"
         },
         "source-url": {
             "description": "A URL pointing to a `nix-installer` executable",
@@ -105,7 +105,7 @@
         "using": "composite",
         "steps": [
             {
-                "uses": "DeterminateSystems/nix-installer-action@86cbc893b3c44423bb3b27da33c306deba1e1ef4",
+                "uses": "DeterminateSystems/nix-installer-action@95f009f8cba987d36d7e3396d29de81b2883654a",
                 "with": {
                     "extra-conf": "${{ inputs.extra-conf }}",
                     "github-server-url": "${{ inputs.github-server-url }}",
diff --git a/flake.lock b/flake.lock
index 5216308..d37a53a 100644
--- a/flake.lock
+++ b/flake.lock
@@ -2,12 +2,12 @@
   "nodes": {
     "nixpkgs": {
       "locked": {
-        "lastModified": 1771008912,
-        "narHash": "sha256-gf2AmWVTs8lEq7z/3ZAsgnZDhWIckkb+ZnAo5RzSxJg=",
-        "rev": "a82ccc39b39b621151d6732718e3e250109076fa",
-        "revCount": 945868,
+        "lastModified": 1771848320,
+        "narHash": "sha256-0MAd+0mun3K/Ns8JATeHT1sX28faLII5hVLq0L3BdZU=",
+        "rev": "2fc6539b481e1d2569f25f8799236694180c0993",
+        "revCount": 953160,
         "type": "tarball",
-        "url": "https://api.flakehub.com/f/pinned/NixOS/nixpkgs/0.1.945868%2Brev-a82ccc39b39b621151d6732718e3e250109076fa/019c5b2e-592f-7d17-b9ce-868f25acfeca/source.tar.gz"
+        "url": "https://api.flakehub.com/f/pinned/NixOS/nixpkgs/0.1.953160%2Brev-2fc6539b481e1d2569f25f8799236694180c0993/019c8e05-d2f6-7c7e-9ead-612154b18bfb/source.tar.gz"
       },
       "original": {
         "type": "tarball",
diff --git a/tools/state.json b/tools/state.json
index d443297..1af7049 100644
--- a/tools/state.json
+++ b/tools/state.json
@@ -1,5 +1,5 @@
 {
-  "nix_installer_action_revision": "86cbc893b3c44423bb3b27da33c306deba1e1ef4",
-  "determinate_nix_tag": "v3.16.0",
+  "nix_installer_action_revision": "95f009f8cba987d36d7e3396d29de81b2883654a",
+  "determinate_nix_tag": "v3.16.3",
   "checkout_action_tag": "v6.0.2"
 }