diff --git a/modules/ppcp-api-client/src/Factory/PurchaseUnitFactory.php b/modules/ppcp-api-client/src/Factory/PurchaseUnitFactory.php
index 9f8f12c5e..e66de1c7e 100644
--- a/modules/ppcp-api-client/src/Factory/PurchaseUnitFactory.php
+++ b/modules/ppcp-api-client/src/Factory/PurchaseUnitFactory.php
@@ -110,7 +110,7 @@ class PurchaseUnitFactory {
 		$items    = array_filter(
 			$this->item_factory->from_wc_order( $order ),
 			function ( Item $item ): bool {
-				return $item->unit_amount()->value() > 0;
+				return $item->unit_amount()->value() >= 0;
 			}
 		);
 		$shipping = $this->shipping_factory->from_wc_order( $order );
@@ -166,7 +166,7 @@ class PurchaseUnitFactory {
 		$items  = array_filter(
 			$this->item_factory->from_wc_cart( $cart ),
 			function ( Item $item ): bool {
-				return $item->unit_amount()->value() > 0;
+				return $item->unit_amount()->value() >= 0;
 			}
 		);