From ce6259e11200691c4bc83e47ee4567bd6ba6147c Mon Sep 17 00:00:00 2001
From: Florian Ceprika <f.ceprika@gmail.com>
Date: Wed, 28 Jan 2026 10:38:32 +0100
Subject: [PATCH] Fix DivisionByZeroError in creditmemo tax for zero base
 shipping amount

---
 app/code/Magento/Sales/Model/Order/Creditmemo/Total/Tax.php | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/app/code/Magento/Sales/Model/Order/Creditmemo/Total/Tax.php b/app/code/Magento/Sales/Model/Order/Creditmemo/Total/Tax.php
index 68b4afc79570..0f5dfa0bb0c7 100644
--- a/app/code/Magento/Sales/Model/Order/Creditmemo/Total/Tax.php
+++ b/app/code/Magento/Sales/Model/Order/Creditmemo/Total/Tax.php
@@ -134,8 +134,9 @@ public function collect(Creditmemo $creditmemo)
             $baseShippingDiscountTaxCompensationAmount = 0;
             $shippingDelta = $baseOrderShippingAmount - $baseOrderShippingRefundedAmount;
 
-            if ($orderShippingAmount > 0 && ($shippingDelta > $creditmemo->getBaseShippingAmount() ||
-                $this->isShippingIncludeTaxWithTaxAfterDiscount($order->getStoreId()))) {
+            if ($orderShippingAmount > 0 && $baseOrderShippingAmount > 0
+                && ($shippingDelta > $creditmemo->getBaseShippingAmount()
+                || $this->isShippingIncludeTaxWithTaxAfterDiscount($order->getStoreId()))) {
                 $part = $creditmemo->getShippingAmount() / $orderShippingAmount;
                 $basePart = $creditmemo->getBaseShippingAmount() / $baseOrderShippingAmount;
                 $shippingTaxAmount = $order->getShippingTaxAmount() * $part;