diff --git a/src/Gateway.php b/src/Gateway.php
index adf65ee..213f1b4 100644
--- a/src/Gateway.php
+++ b/src/Gateway.php
@@ -116,7 +116,7 @@ public function start( Payment $payment ) {
 				$price = null;
 
 				if ( null !== $line->get_unit_price() ) {
-					$price = $line->get_unit_price()->get_including_tax()->get_cents();
+					$price = $line->get_unit_price()->get_including_tax()->get_minor_units()->to_int();
 				}
 
 				$order_data[] = array(