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Address lookup API

Provides the fastest and most reliable way to capture accurate addresses. Ensure data quality and create the best user experience with PostCoder.

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Improve database quality

Populate your database with the best quality data by capturing addresses at the point of entry.

Improve user experience

Create the best possible experience by providing a quick and easy way to fill-in addresses.

Improve business efficiency

Improve form conversions and reduce delivery issues with address validation and accurate data.


Postcode lookup

Optimised to handle typos, misplaced characters, and even out-dated postcodes.

Address autocomplete

Provides real-time suggestions as you type, handling abbreviated words and common typos seamlessly.

Quick setup

Install on a website or app in the same way as you integrate Google Maps or PayPal.

Reliable source data

Combines the very latest data from suppliers like Royal Mail, OS, Eircode and USPS.

Payment models

Pay for lookups in advance and use optional auto top-up, or pay monthly or yearly.


Supports HTTPS to ensure the addresses you lookup are encrypted from end to end.

Try address lookup

See how it works with UK postcodes

Postcode lookup demo

Try address autocomplete

Just start typing for instant results

Trusted by 9,000 businesses

“Our checkout page needs to be quick and efficient to cope with the huge demand. The help of PostCoder has had major benefits to our business”

- Alex Woods, Victorian Plumbing

Read the case study »

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The most up-to-date address database

PostCoder is refreshed daily using the most up-to-date and comprehensive data straight from official sources including Royal Mail and Ordnance Survey.

30M+ addresses   1.8M postcodes   1.4M business names   4,500 updates every day

Use PostCoder across your business

Checkout and registration forms

Use address lookup to help customers fill in their details more easily. Capture higher quality addresses from the start.

CRMs and office apps

Help your staff spend less time typing in addresses and more time concentrating on your customers and their needs.

EPOS systems

Speed-up customer refunds and improve address accuracy by including postcode lookup in your returns procedure.

Mobile apps

Improve usability on devices with smaller interfaces by using postcode lookup whenever you ask for an address.

Use PostCoder across your business

A simple API for developers

Sign up for an API key and get free lookups to try

Cross platform postcode lookup using the PostCoder Web API

Easy to integrate examples
Secure HTTPS requests
Reporting tools and usage alerts
350ms real-world response time
Enterprise SLA available

API documentation
Get your API key

Improve your forms in other ways

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