diff --git a/CHANGELOG.md b/CHANGELOG.md
index 0fbbb5ea..37e76de7 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,6 +8,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ## [Unreleased]
 ### Changed
 - ci: Run workflows against 5.x.x branches ([#859](https://github.com/jsonrainbow/json-schema/pull/859))
+### Fixed
+- UriValidator: Allow `file:/` and `file:///` ([#856](https://github.com/jsonrainbow/json-schema/discussions/856))
 
 ## [6.6.3] - 2025-12-02
 ### Changed
diff --git a/src/JsonSchema/Tool/Validator/UriValidator.php b/src/JsonSchema/Tool/Validator/UriValidator.php
index c5e2cf6e..178fce91 100644
--- a/src/JsonSchema/Tool/Validator/UriValidator.php
+++ b/src/JsonSchema/Tool/Validator/UriValidator.php
@@ -21,7 +21,7 @@ public static function isValid(string $uri): bool
 
         // RFC 3986: Non-Hierarchical URIs (mailto, data, urn, news)
         $nonHierarchicalPattern = '/^
-                (mailto|data|urn|news|tel):          # Only allow known non-hierarchical schemes
+                (mailto|data|urn|news|tel|file):     # Only allow known non-hierarchical schemes
                 (.+)                                 # Must contain at least one character after scheme
         $/ix';
 
diff --git a/tests/Tool/Validator/UriValidatorTest.php b/tests/Tool/Validator/UriValidatorTest.php
index 7eedaca8..69b7282e 100644
--- a/tests/Tool/Validator/UriValidatorTest.php
+++ b/tests/Tool/Validator/UriValidatorTest.php
@@ -34,6 +34,9 @@ public function validUriDataProvider(): \Generator
         yield 'OASIS URN URI' => ['uri' => 'urn:oasis:names:specification:docbook:dtd:xml:4.1.2'];
         yield 'Custom URI with underscore' => ['uri' => 'custom://reg_name/path/file.json'];
         yield 'Custom URI with tilde' => ['uri' => 'custom://reg~name/path/file.json'];
+        yield 'File URI with implicit localhost (empty host)' => ['uri' => 'file:///path/to/file.txt'];
+        yield 'File URI with explicit host' => ['uri' => 'file://some-host/path/to/file.txt'];
+        yield 'File URI without any host' => ['uri' => 'file:/path/to/file.txt'];
     }
 
     public function invalidUriDataProvider(): \Generator