Pay-on-Scan Return Labels in Shopify: When the Billing Model Helps and Where It Hides Your Cost

A return label you only pay for if it gets scanned fixes one problem, unused labels, and leaves a bigger one alone: the price you see when you create it is an estimate.

What pay-on-scan billing actually does

Shopify's FedEx return labels, added to the admin in its Winter '26 Edition, use pay-on-scan billing. You are not charged when you create the label. You are charged after the carrier scans the package.

Two details matter for your math. A pay-on-scan label cannot be voided or canceled, because there is nothing to refund. And the price shown at creation is an estimate, since the carrier weighs and measures the package at scan and sets the final cost then.

What it fixes

With a prepaid label, every label you generate for a return that never ships is cash you have to chase back. With pay-on-scan, an unused label costs nothing. For stores that issue labels automatically at return approval, that removes a small, steady leak and the reconciliation work that goes with it.

What it does not fix

The cost of a used label is still set by weight, box size and zone. Customers pack returns in whatever box they have, so the final charge can land above the estimate. Your return cost per used label becomes a range, not a number you can lock in on day one.

That matters most if you charge a flat return fee. A flat fee set against the estimate can drift negative on heavy or oversized returns.

How to price return fees under pay-on-scan

1. Pull 30 days of used return labels and compare the estimate with the final charge.
2. Calculate the average gap and the 90th percentile gap, not just the average.
3. Set the fee against the estimate plus a buffer sized to that gap, or tier it by item weight.
4. Re-check the gap monthly during peak, when carrier surcharges and customer packing both change.

A simple example

These numbers are illustrative. Say 100 return labels are created in a month and 60 are used. Under a prepaid model you pay for 100 and recover 40 later, if you track it. Under pay-on-scan you pay for 60 at the final scanned price.

If the estimate was $8.00 and the average final charge was $8.70, your 60 labels cost $522 instead of the $480 you would have forecast. The unused-label saving is real, and so is the $42 surprise. Plan for both.

Where it fits and where it does not

Pay-on-scan suits stores that create a lot of labels but see a modest share actually used, because the saving scales with the unused share. It is a weaker fit if most of your returns are heavy, bulky or packed in odd boxes, since the gap between estimate and final charge will dominate.

Either way, the label is only one line of return cost. Handling, restocking and the refund itself usually outweigh it.

Before you switch, check four things

• What share of the labels you create are actually used today.
• How far final charges run above estimates on your heaviest return categories.
• Whether your return fee is flat, tiered or percentage-based.
• Who reconciles the monthly carrier invoice against return approvals.

ShipAid Returns & Exchanges gives merchants discounted labels with no monthly software fee, and lets you set return fees yourself so the label cost and the fee you charge stay in line. See how it fits your return flow at shipaid.com.