The buyer is ready to pay, but the delivery address belongs to an old apartment. A final review can catch that mistake only if the address is visible and changing it does not restart the checkout. WCAG 2.2’s error-prevention criterion treats financial commitments as actions that need a way to prevent or undo consequential errors. For a checkout using review and confirmation, the important work is the path from spotting a mistake to approving the corrected order.
Review is one route to preventing a costly mistake
Success Criterion 3.3.4 requires at least one of three alternatives for the submissions it covers. They are alternatives, rather than a requirement to add three separate safeguards to every checkout.
| Route in WCAG 3.3.4 | What it provides | Design question for a purchase |
|---|---|---|
| Reversible | The submission can be reversed | Can the buyer actually undo the commitment? |
| Checked | Input is checked for errors, with an opportunity to correct them | Which errors can the system identify? |
| Confirmed | Information can be reviewed, confirmed and corrected before final submission | Can the buyer inspect the purchase and change it before paying? |
This is why a separate review page is not universally required by that criterion. A review mechanism can take different forms. The W3C explanation includes a retailer showing order details so the customer can confirm them or make changes; the practical goal is an effective opportunity to correct the purchase.
Some mistakes are valid inputs. An old address can have a correct postal code. Two lamps can be a permitted quantity even when the buyer intended one. A review helps the person recognize those mistakes when validation alone cannot.
Show the order in the terms the buyer recognizes
Here is a hypothetical order review for two desk lamps. The prices, delivery charge and tax amount are invented, in US dollars; the tax is a stipulated amount, not a jurisdiction’s tax calculation.
| Review section | What the buyer sees | Correction offered |
|---|---|---|
| Items | Desk lamp; amber shade; black base; quantity 2; $80 each | Change items |
| Delivery address | The full address the buyer entered, including apartment detail | Change delivery address |
| Delivery service | Standard delivery; $12; the current arrival estimate | Change delivery service |
| Payment | The recognizable selected method, with only appropriate masked details | Change payment method |
| Amount | Items $160 + delivery $12 + tax $14 = $186 total | Changes return through the relevant section |
| Commitment | One-time purchase; no recurring charge | Review the actual offer if a different purchase type is selected |
The final action in this example could be “Pay $186.” The button’s wording and amount must match what happens when it is pressed. If another confirmation step follows, name that next action instead of implying that payment occurs here.
Use the selected variant’s name, not just a generic product title or a thumbnail. A photograph may not make a small color difference obvious. The quantity and unit price should remain readable together so the buyer can reconstruct the order total without returning to the cart.
For a subscription, the equivalent review would need to explain the recurring commitment as well as today’s charge. That is a different purchase from this one-time example. The review should reflect what the buyer selected, rather than displaying the same reassuring line for every offer.
A change link should return to the same decision
The GOV.UK check-answers pattern gives a concrete approach: put a change link beside the relevant section, preserve previously entered answers and return the user to review after the correction. Its examples add context to repeated change links for screen-reader users.
Applied to the lamp order, “Change delivery address” should open the address already entered. After the buyer fixes the apartment number, the flow should return to the updated order review. It should not demand another tour through unchanged billing and contact screens.
There is an important exception in the same guidance: if the changed answer creates new questions, ask those before returning. A different destination may require a new delivery choice. Preserving the old selection without checking its availability would make the review look complete while leaving the order unresolved.
Recalculate the commitment after a correction
Suppose the buyer changes delivery from the hypothetical $12 option to an $18 option. With the other illustrated amounts unchanged, the total becomes $192. The updated review must show both the new service and the new total before the final action.
The design problem is not solved by changing only the number on the button. The buyer needs enough context to understand why the total changed. Keep the revised delivery charge in the cost breakdown and show the associated arrival estimate in the delivery section.
Follow the same reasoning when a quantity change affects stock, a variant changes the price or an address changes a delivery service. Recompute what depends on the changed answer. If that produces another choice, bring the buyer to that choice before presenting the final review again.
The W3C review-and-correct technique is useful here because it treats correction as part of the transaction. A summary that reflects old information after an edit is not a meaningful final check.
Inspect the correction loop, not just the summary
Give a reviewer a specific mistake to repair: the wrong quantity, a missing apartment number or a delivery option that no longer suits the purchase. Ask them to describe the order they will receive and the amount they expect to pay after making the change. Compare that description with the order the system is ready to accept.
Repeat the correction using a keyboard and with assistive technology appropriate to the checkout. The review should make the relevant section and its action understandable without relying on color or position alone. Checking this pattern does not establish conformance for the whole site; it examines a particular purchase task.
Finally, distinguish the review from the receipt. Before the final action, make it clear that the order has not yet been placed. After success, show the accepted order. Those two screens answer different questions: “Is this what I want to buy?” and “What did the business accept?”