Most returns in sized categories aren’t a rejection of the brand; it didn’t fit, or the color was off. An exchange keeps the sale and the customer, and in chapter 4’s example was worth about $33 more than a refund. The portal’s job is to make it the easiest right answer.

Order the choices

1. Exchange for the right oneSame item, other size or color, pre-selected from the reason. “Too small” should open with the next size up already chosen.
2. Store credit, with a bonus if you use oneFor customers who want something else. Let them shop from the portal and apply the credit at once.
3. Refund to the original payment methodVisible on the same screen, in the same type size. Hiding it doesn’t keep customers; it teaches them to distrust you, and in some places it breaks the law (chapter 13).

In the meta-analysis in chapter 2, exchange leniency reduced returns Published. A 2026 study of a fast-fashion retailer found that customers who visited a store to collect or return an online order were more likely to exchange; follow-up analyses suggest seeing the product reduced uncertainty Published. Without stores, borrow the mechanism: at the moment of exchange, answer the fit question, for example with what customers who returned for “runs small” chose instead.

Instant exchanges

An exchange that ships only when the old item reaches the warehouse can take two weeks, and by then the customer has bought elsewhere. Ship at the first carrier scan, or at the request for trusted customers, using the trust tiers in chapter 8.

Bonus credit

Loop, a returns platform for Shopify stores, reports that across more than 4,000 merchants in the year to October 2025, 73.6% offered exchanges and 49.2% let customers shop with their credit in the portal; of those, 51.7% added a bonus, averaging $11.28 Reported. That’s vendor data: it tells you what’s common, not what works.

What works depends on how many customers the bonus moves, since it’s paid to everyone who exchanges, including those who would have anyway. The chapter 4 tool gives the break-even share. Keep it a flat amount, spent at once in the portal, not on deeply discounted items, and tested against a holdout.

A bonus is paid to everyone who exchanges. It only earns on the ones it changed.

Make sure the exchange sticks

An exchange that comes back is a refund with extra shipping. If “too small” exchanges come back as “too big”, your size guidance is the problem; that’s a fix for chapter 10.

Do this

• Reorder your outcome screen this week: exchange, then credit, then refund, all visible. Record the outcome mix for four weeks before and after.
• Set up the bonus as a holdout, with the break-even share from the chapter 4 tool written down before it starts.