diff --git a/src/Http/Resolvers/HeaderIdentityResolver.php b/src/Http/Resolvers/HeaderIdentityResolver.php
index 984a463..a881648 100644
--- a/src/Http/Resolvers/HeaderIdentityResolver.php
+++ b/src/Http/Resolvers/HeaderIdentityResolver.php
@@ -38,9 +38,9 @@ public function getHeader(): string
     public function getRequestHeaderName(Tenancy $tenancy): string
     {
         return str_replace(
-            ['{tenancy}', '{resolver}'],
-            [$tenancy->getName(), $this->getName()],
-            $this->header
+            ['{tenancy}', '{resolver}', '{Tenancy}', '{Resolver}'],
+            [$tenancy->getName(), $this->getName(), ucfirst($tenancy->getName()), ucfirst($this->getName())],
+            $this->getHeader()
         );
     }
 
diff --git a/tests/Resolvers/HeaderResolverTest.php b/tests/Resolvers/HeaderResolverTest.php
new file mode 100644
index 0000000..0de95d6
--- /dev/null
+++ b/tests/Resolvers/HeaderResolverTest.php
@@ -0,0 +1,69 @@
+<?php
+declare(strict_types=1);
+
+namespace Sprout\Tests\Resolvers;
+
+use Illuminate\Config\Repository;
+use Illuminate\Foundation\Testing\RefreshDatabase;
+use Illuminate\Routing\Router;
+use Orchestra\Testbench\Concerns\WithWorkbench;
+use Orchestra\Testbench\TestCase;
+use PHPUnit\Framework\Attributes\Test;
+use Sprout\Attributes\CurrentTenant;
+use Sprout\Contracts\Tenant;
+use Workbench\App\Models\TenantModel;
+
+class HeaderResolverTest extends TestCase
+{
+    use WithWorkbench, RefreshDatabase;
+
+    protected $enablesPackageDiscoveries = true;
+
+    protected function defineEnvironment($app): void
+    {
+        tap($app['config'], static function (Repository $config) {
+            $config->set('multitenancy.providers.tenants.model', TenantModel::class);
+            $config->set('multitenancy.defaults.resolver', 'header');
+        });
+    }
+
+    protected function defineRoutes($router)
+    {
+        $router->get('/', function () {
+            return 'no';
+        });
+
+        $router->tenanted(function (Router $router) {
+            $router->get('/header-route', function (#[CurrentTenant] Tenant $tenant) {
+                return $tenant->getTenantKey();
+            })->name('header.route');
+        }, 'header', 'tenants');
+    }
+
+    #[Test]
+    public function resolvesFromRoute(): void
+    {
+        $tenant = TenantModel::first();
+
+        $result = $this->get(route('header.route'), ['Tenants-Identifier' => $tenant->getTenantIdentifier()]);
+
+        $result->assertOk();
+        $result->assertContent((string)$tenant->getTenantKey());
+    }
+
+    #[Test]
+    public function throwsExceptionForInvalidTenant(): void
+    {
+        $result = $this->get(route('header.route'), ['Tenants-Identifier' => 'i-am-not-real']);
+
+        $result->assertInternalServerError();
+    }
+
+    #[Test]
+    public function throwsExceptionWithoutHeader(): void
+    {
+        $result = $this->get(route('header.route'));
+
+        $result->assertInternalServerError();
+    }
+}