UK address validation for eCommerce

Get the address right at the checkout, not at the depot

AddressBrain adds Royal Mail-licensed address autocomplete and validation to your checkout. Shoppers pick their address in three keystrokes, and fewer parcels come back to you.
Free trial: 30 lookups a day for 30 days. No card required.
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Royal Mail
Sub-50ms response times
Free trial, no card required
Checkout address form with UK postcode lookup suggesting Royal Mail PAF addresses
Already validating addresses for
The cost of a typed address

One wrong address, and you pay for the same order twice

You spent money getting that shopper to the basket. Then you asked them to type five fields on a phone, on the train, one-handed. They guess the postcode, drop the flat number, and press pay anyway.
Nothing looks wrong until the parcel comes back. By then you have paid to ship it, paid to bring it home, answered the ticket and refunded the delivery charge.

The address fields are where checkout
momentum dies

Five free-text boxes is the longest stretch of typing in your whole funnel. Autofill for address fields increases form completion by 25% and reduces time to complete by 30%.

20% of online addresses have an error in it

Roughly one in five addresses entered online contains a mistake. When the address is inaccurate or incomplete, 39% of deliveries fail, and 41% arrive late.

Your team absorbs the cost, not the courier

Re-delivery fees, a support ticket, a goodwill refund, and a shopper who is now less likely to order from you again.
Autocomplete and address search

Shoppers pick their address. They stop typing it.

Add as-you-type completion to the address field in your checkout. Three or four characters and the full, correctly formatted address drops straight into your form. There is nothing left for the shopper to get wrong.
Search on a postcode, a partial address or a business name.
Returns clean, structured, PAF-formatted fields, not one long string.
1.4m UK business names included, for work and click-and-collect deliveries.
Fewer boxes on screen, which matters most on mobile.
UK address autocomplete letting shoppers pick their address instead of typing it
Postcode lookup and validation

Catch the bad ones before they reach the packing bench.

Not every order comes through your own checkout. Marketplace orders, phone orders and imported customer records often arrive with no validation at all. Run them through the lookup API and get a full, normalised address list back for any UK postcode.
Validates and normalises the data, one order at a time or in a batch.
New-build addresses and UK business names included at no extra cost.
Clean the customer records you already hold before the next campaign.
Flag undeliverable addresses before you print the label.
Address validation catching an undeliverable UK address before dispatch
Built for whoever builds your checkout

One request and your developer can have this live this afternoon.

No sales call, no scoping session, no procurement round before anyone can test it. Create an account, copy the key out of the dashboard, and make the first call. Here’s the whole integration.
Authenticate with a single API bearer token, no OAuth handshake.
Free trial includes 30 lookups a day for 30 days. No card required.
Live usage dashboard, so you can watch spend as it happens.
Distributed, auto-scaling architecture, so peak trading traffic does not queue behind one database.
Example AddressBrain API request and JSON response showing a UK address lookup
On every plan, including free

What you get out of the box

Sub-50ms UK response times.

Full PAF-formatted address data, including new-build coverage.

Batch and single-lookup validation on the same key.

Start building in minutes

Create a free account and start returning validated UK addresses in minutes.Start with 30 free lookups a day for 30 days. Test environment, full API docs, and support included.
No credit card required. Officially licensed by Royal Mail.