diff --git a/src/TrackConfirm.php b/src/TrackConfirm.php
index 02e3334..bebaa59 100644
--- a/src/TrackConfirm.php
+++ b/src/TrackConfirm.php
@@ -18,7 +18,7 @@ class TrackConfirm extends USPSBase
 
     public function getEndpoint()
     {
-        return self::$testMode ? 'http://production.shippingapis.com/ShippingAPITest.dll' : 'http://production.shippingapis.com/ShippingAPI.dll';
+        return self::$testMode ? 'https://production.shippingapis.com/ShippingAPITest.dll' : 'https://production.shippingapis.com/ShippingAPI.dll';
     }
 
     /**
diff --git a/src/USPSBase.php b/src/USPSBase.php
index 71f4d26..9bc8b9a 100644
--- a/src/USPSBase.php
+++ b/src/USPSBase.php
@@ -13,7 +13,7 @@
 abstract class USPSBase
 {
     const LIVE_API_URL = 'https://secure.shippingapis.com/ShippingAPI.dll';
-    const TEST_API_URL = 'http://production.shippingapis.com/ShippingAPITest.dll';
+    const TEST_API_URL = 'https://production.shippingapis.com/ShippingAPITest.dll';
 
     /**
      * @var string - the usps username provided by the usps website