diff --git a/framework/core/src/Api/UrlGenerator.php b/framework/core/src/Api/UrlGenerator.php
index 748e218de..003d2d607 100644
--- a/framework/core/src/Api/UrlGenerator.php
+++ b/framework/core/src/Api/UrlGenerator.php
@@ -14,5 +14,8 @@ use Flarum\Http\AbstractUrlGenerator;
 
 class UrlGenerator extends AbstractUrlGenerator
 {
+    /**
+     * {@inheritdoc}
+     */
     protected $prefix = 'api';
 }
diff --git a/framework/core/src/Http/AbstractUrlGenerator.php b/framework/core/src/Http/AbstractUrlGenerator.php
index e905fdbf9..1d0426984 100644
--- a/framework/core/src/Http/AbstractUrlGenerator.php
+++ b/framework/core/src/Http/AbstractUrlGenerator.php
@@ -30,6 +30,11 @@ class AbstractUrlGenerator
      */
     protected $path;
 
+    /**
+     * @var string
+     */
+    protected $prefix = '';
+
     /**
      * @param Application $app
      * @param RouteCollection $routes
@@ -67,12 +72,18 @@ class AbstractUrlGenerator
     }
 
     /**
-     * Get the base URL.
+     * Generate a URL to base with UrlGenerator's prefix.
      *
      * @return string
      */
     public function toBase()
     {
-        return $this->app->url($this->path);
+        $base = $this->app->url($this->path);
+
+        if (empty($this->prefix)) {
+            return $base;
+        } else {
+            return $base . '/' . $this->prefix;
+        }
     }
 }