Change product options: quantities, sizes and colours

Customers can raise or lower a quantity, or swap an item for another size or colour of the same product, from their order page. Raising a quantity shows exactly what it will cost, in your store's currency, before anything is charged, and a customer who raised it by mistake can lower it again straight away. Lowering a quantity refunds the difference. Tacey checks your real stock before offering a swap, a swap keeps any quantity the customer already reduced, and a refusal explains itself in plain words. Reducing or removing items is a switch you can turn off. An order can never be reduced to nothing (the customer is pointed to cancelling instead), and an order containing a subscription item is refused rather than edited.