diff --git a/app/Core/Session/SessionManager.php b/app/Core/Session/SessionManager.php
index 0ce0254..7628992 100644
--- a/app/Core/Session/SessionManager.php
+++ b/app/Core/Session/SessionManager.php
@@ -79,6 +79,18 @@ class SessionManager extends Base
         session_destroy();
     }
 
+    /**
+     * Get the session cookie path, without the trailing slash
+     *
+     * @access public
+     * @return string
+     */
+    public function getCookiePath()
+    {
+        $path = rtrim((string) $this->helper->url->dir(), '/');
+        return $path === '' ? '/' : $path;
+    }
+
     /**
      * Define session settings
      *
@@ -89,7 +101,7 @@ class SessionManager extends Base
         // Session cookie: HttpOnly and secure flags
         session_set_cookie_params(
             SESSION_DURATION,
-            $this->helper->url->dir() ?: '/',
+            $this->getCookiePath(),
             null,
             $this->request->isHTTPS(),
             true
diff --git a/tests/units/Core/Session/SessionManagerTest.php b/tests/units/Core/Session/SessionManagerTest.php
new file mode 100644
index 0000000..f2dbb0a
--- /dev/null
+++ b/tests/units/Core/Session/SessionManagerTest.php
@@ -0,0 +1,38 @@
+<?php
+
+namespace KanboardTests\units\Core\Session;
+
+use KanboardTests\units\Base;
+use Kanboard\Core\Http\Request;
+use Kanboard\Core\Session\SessionManager;
+
+class SessionManagerTest extends Base
+{
+    public function testCookiePathAtRoot()
+    {
+        $this->assertEquals('/', $this->buildSessionManager('/index.php')->getCookiePath());
+    }
+
+    public function testCookiePathInSubDirectoryHasNoTrailingSlash()
+    {
+        $this->assertEquals('/kanboard', $this->buildSessionManager('/kanboard/index.php')->getCookiePath());
+    }
+
+    public function testCookiePathInNestedSubDirectoryHasNoTrailingSlash()
+    {
+        $this->assertEquals('/apps/kanboard', $this->buildSessionManager('/apps/kanboard/index.php')->getCookiePath());
+    }
+
+    private function buildSessionManager($phpSelf)
+    {
+        $this->container['request'] = new Request(
+            $this->container,
+            array(
+                'PHP_SELF' => $phpSelf,
+                'REQUEST_METHOD' => 'GET',
+            )
+        );
+
+        return new SessionManager($this->container);
+    }
+}