diff --git a/CHANGELOG.md b/CHANGELOG.md
index f595f2ba15..641f4262cf 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,7 @@
 
 ## Unreleased
 
+- Improved product query performance. ([#4281](https://github.com/craftcms/commerce/issues/4281))
 - Fixed a bug where Users’ orders, carts, and subscriptions weren’t retaining their view options on the dedicated “Commerce” screen within Edit User.
 
 ## 5.6.2 - 2026-04-15
diff --git a/src/elements/db/ProductQuery.php b/src/elements/db/ProductQuery.php
index 168c9c7767..bce927bc1b 100644
--- a/src/elements/db/ProductQuery.php
+++ b/src/elements/db/ProductQuery.php
@@ -755,7 +755,10 @@ protected function afterPrepare(): bool
 
             $this->subQuery->leftJoin(['catalogprices' => $catalogPricesQuery], '[[catalogprices.purchasableId]] = [[commerce_products.defaultVariantId]] AND [[catalogprices.storeId]] = [[sitestores.storeId]]');
         } else {
-            $this->subQuery->leftJoin(['purchasablesstores' => Table::PURCHASABLES_STORES], '[[purchasablesstores.storeId]] = [[sitestores.storeId]] AND [[purchasablesstores.purchasableId]] = [[commerce_products.defaultVariantId]]');
+            // For speed in Postgres we only need this if the `defaultPrice` criteria is being used.
+            if (isset($this->defaultPrice)) {
+                $this->subQuery->leftJoin(['purchasablesstores' => Table::PURCHASABLES_STORES], '[[purchasablesstores.storeId]] = [[sitestores.storeId]] AND [[purchasablesstores.purchasableId]] = [[commerce_products.defaultVariantId]]');
+            }
         }
 
         return parent::afterPrepare();