diff --git a/.changeset/dependencies-GH-306.md b/.changeset/dependencies-GH-306.md
new file mode 100644
index 00000000..12eaf874
--- /dev/null
+++ b/.changeset/dependencies-GH-306.md
@@ -0,0 +1,5 @@
+---
+"@tcd-devkit/tsconfig": patch
+---
+
+chore(deps): update dependency prettier to v3.9.4
diff --git a/package.json b/package.json
index 0da34e07..ef329b74 100644
--- a/package.json
+++ b/package.json
@@ -39,7 +39,7 @@
     "@tcd-devkit/tsconfig": "workspace:*",
     "eslint": "9.39.1",
     "husky": "9.1.7",
-    "prettier": "3.6.2",
+    "prettier": "3.9.4",
     "turbo": "2.6.1",
     "typescript": "5.9.3"
   },
diff --git a/packages/tsconfig/package.json b/packages/tsconfig/package.json
index 8ebae575..99cc7892 100644
--- a/packages/tsconfig/package.json
+++ b/packages/tsconfig/package.json
@@ -30,6 +30,6 @@
     "tsconfig.*.json"
   ],
   "devDependencies": {
-    "prettier": "3.6.2"
+    "prettier": "3.9.4"
   }
 }
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index 9e866b8c..c4a9a066 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -42,8 +42,8 @@ importers:
         specifier: 9.1.7
         version: 9.1.7
       prettier:
-        specifier: 3.6.2
-        version: 3.6.2
+        specifier: 3.9.4
+        version: 3.9.4
       turbo:
         specifier: 2.6.1
         version: 2.6.1
@@ -634,8 +634,8 @@ importers:
   packages/tsconfig:
     devDependencies:
       prettier:
-        specifier: 3.6.2
-        version: 3.6.2
+        specifier: 3.9.4
+        version: 3.9.4
 
   packages/tsup-config:
     devDependencies:
@@ -2317,6 +2317,7 @@ packages:
   git-raw-commits@4.0.0:
     resolution: {integrity: sha512-ICsMM1Wk8xSGMowkOmPrzo2Fgmfo4bMHLNX6ytHjajRJUqvHOw/TFapQ+QG75c3X/tTDDhOSRPGC52dDbNM8FQ==}
     engines: {node: '>=16'}
+    deprecated: Deprecated and no longer maintained. Use @conventional-changelog/git-client instead.
     hasBin: true
 
   glob-parent@5.1.2:
@@ -3052,6 +3053,11 @@ packages:
     engines: {node: '>=14'}
     hasBin: true
 
+  prettier@3.9.4:
+    resolution: {integrity: sha512-yWG/o/4oJfo036EKAfK6ACAoDOfHeRHx4tuxkfBZiauURiaSmYwlpOr5LQqKtIkRD2z1PLteme2WoxEnj4tHTg==}
+    engines: {node: '>=14'}
+    hasBin: true
+
   pretty-ms@9.3.0:
     resolution: {integrity: sha512-gjVS5hOP+M3wMm5nmNOucbIrqudzs9v/57bWRHQWLYklXqoXKrVfYW2W9+glfGsqtPgpiz5WwyEEB+ksXIx3gQ==}
     engines: {node: '>=18'}
@@ -6070,6 +6076,8 @@ snapshots:
 
   prettier@3.6.2: {}
 
+  prettier@3.9.4: {}
+
   pretty-ms@9.3.0:
     dependencies:
       parse-ms: 4.0.0