diff --git a/.changes/nextrelease/endpoints-tests.json b/.changes/nextrelease/endpoints-tests.json
new file mode 100644
index 0000000000..ca830e40a4
--- /dev/null
+++ b/.changes/nextrelease/endpoints-tests.json
@@ -0,0 +1,7 @@
+[
+  {
+    "type": "enhancement",
+    "category": "EndpointV2",
+    "description": "Adds terminal failure if endpoints file cannot be found"
+  }
+]
\ No newline at end of file
diff --git a/src/EndpointV2/EndpointDefinitionProvider.php b/src/EndpointV2/EndpointDefinitionProvider.php
index aee14b5eee..6da2685cea 100644
--- a/src/EndpointV2/EndpointDefinitionProvider.php
+++ b/src/EndpointV2/EndpointDefinitionProvider.php
@@ -8,14 +8,14 @@
  */
 class EndpointDefinitionProvider
 {
-    public static function getEndpointRuleset($service, $apiVersion)
+    public static function getEndpointRuleset($service, $apiVersion, $baseDir = null)
     {
-        return self::getData($service, $apiVersion, 'ruleset');
+        return self::getData($service, $apiVersion, 'ruleset', $baseDir);
     }
 
-    public static function getEndpointTests($service, $apiVersion)
+    public static function getEndpointTests($service, $apiVersion, $baseDir = null)
     {
-        return self::getData($service, $apiVersion, 'tests');
+        return self::getData($service, $apiVersion, 'tests', $baseDir);
     }
 
     public static function getPartitions()
@@ -30,9 +30,9 @@ public static function getPartitions()
         }
     }
 
-    private static function getData($service, $apiVersion, $type)
+    private static function getData($service, $apiVersion, $type, $baseDir)
     {
-        $basePath = __DIR__ . '/../data';
+        $basePath = $baseDir ? $baseDir :  __DIR__ . '/../data';
         $serviceDir = $basePath . "/{$service}";
         if (!is_dir($serviceDir)) {
             throw new \InvalidArgumentException(
@@ -54,8 +54,12 @@ private static function getData($service, $apiVersion, $type)
 
         if (file_exists($rulesetPath . $fileName . '.json.php')) {
             return require($rulesetPath . $fileName . '.json.php');
-        } else {
+        } elseif (file_exists($rulesetPath . $fileName . '.json')) {
             return json_decode(file_get_contents($rulesetPath . $fileName . '.json'), true);
+        } else {
+            throw new \InvalidArgumentException(
+                'Specified ' . $type . ' endpoint file for ' . $service . ' with api version ' . $apiVersion . ' does not exist.'
+            );
         }
     }
 
diff --git a/tests/EndpointV2/EndpointDefinitionProviderTest.php b/tests/EndpointV2/EndpointDefinitionProviderTest.php
index 359d604dad..953099bc36 100644
--- a/tests/EndpointV2/EndpointDefinitionProviderTest.php
+++ b/tests/EndpointV2/EndpointDefinitionProviderTest.php
@@ -45,4 +45,33 @@ public function testThrowsExceptionOnInvalidApiVersion()
         $this->expectExceptionMessage('Invalid api version.');
         EndpointDefinitionProvider::getEndpointRuleset('s3', '10-22-2022');
     }
+
+    public function getEndpointFileProvider()
+    {
+        return [
+            ['Ruleset'],
+            ['Tests']
+        ];
+    }
+
+    /**
+     * @dataProvider getEndpointFileProvider
+     *
+     * @param $type
+     */
+    public function testThrowsExceptionOnMissingFiles($type)
+    {
+        $method = 'getEndpoint' . $type;
+        $type = strtolower($type);
+        $tmpdir = sys_get_temp_dir();
+        if (!is_dir($tmpdir . '/data/foo-service/08-05-1989/')) {
+            mkdir($tmpdir . '/data/foo-service/08-05-1989/', 0777, true);
+        }
+        $this->expectException(\InvalidArgumentException::class);
+        $this->expectExceptionMessage("Specified {$type} endpoint file for foo-service with api version 08-05-1989 does not exist.");
+        EndpointDefinitionProvider::$method('foo-service', '08-05-1989', $tmpdir . '/data');
+        rmdir($tmpdir . 'data/' . 's3/' . '/08-05-1989');
+        rmdir($tmpdir . 'data/' . 's3/');
+        rmdir($tmpdir . 'data');
+    }
 }
\ No newline at end of file