diff --git a/config/shopify-integration.php b/config/shopify-integration.php
index 8b72257..891dee5 100644
--- a/config/shopify-integration.php
+++ b/config/shopify-integration.php
@@ -32,5 +32,6 @@
         'amount' => 5.0,
         'currencyCode' => 'USD', // Currently only supports USD
         'interval' => EnsureBilling::INTERVAL_ONE_TIME,
+        'trialDays' => null,
     ],
 ];
diff --git a/src/Lib/EnsureBilling.php b/src/Lib/EnsureBilling.php
index d8e9f4b..8f44392 100644
--- a/src/Lib/EnsureBilling.php
+++ b/src/Lib/EnsureBilling.php
@@ -158,6 +158,7 @@ private static function requestRecurringPayment(Session $session, array $config,
                     ],
                     'returnUrl' => $returnUrl,
                     'test' => ! self::isProd(),
+                    'trialDays' => $config['trialDays'],
                 ],
             ]
         );