Instant Postcode Lookup
Type-ahead search returns full addresses from a postcode or partial address as the user types.
PAF certified · ISO 27001 · Since 2006
Postcode Lookup for the Web
The postcode web service built for developers and businesses that need reliable, fast address data. Our online postcode lookup software plugs into any website or system in minutes, returning PAF-certified UK addresses in under 100ms.
30M+
UK addresses
<100ms
Typical response
2.2p
From, per search
PAF Certified
ISO 27001 & ISO 9001
30M+ UK Addresses
Trusted Since 2006
G-Cloud 15 Supplier
What Is a Postcode Web Service?
A postcode web service is a web-based API that lets any website, app or backend system look up a complete, accurate UK address the moment a customer types a postcode, house number or partial address. Instead of relying on customers to type every line correctly, your form calls the postcode web service, which returns verified Royal Mail address data in real time.
This is the technology behind the address autocomplete you see on the best UK checkout pages, sign-up forms and CRM systems — and it's exactly what our online postcode lookup software delivers, built on a PAF-certified database of over 30 million UK addresses.
Faster checkout
Cut address entry from 8 fields to 2 clicks, reducing form abandonment.
Fewer errors
Every address is validated against Royal Mail PAF data, not guesswork.
Fewer failed deliveries
Accurate addresses mean parcels and post reach customers first time.
Online Postcode Lookup Software Features
Everything you need to add reliable UK address lookup to your website or system
Address Validation
Confirm addresses are real and correctly formatted against Royal Mail PAF before they hit your database.
Data Cleansing
Batch clean, de-duplicate and standardise existing address lists against current PAF data.
REST & SOAP APIs
Simple, well-documented APIs with sample code so developers can integrate in minutes.
Sub-100ms Responses
Typical API responses under 100ms, so lookups feel instant to your users.
Secure & Compliant
HTTPS throughout, ISO 27001 processes and GDPR-aligned handling of personal data.
How the Postcode Web Service Works
Three steps from sign-up to live postcode lookup on your website
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1
Create a free account
Sign up on epostcode.com and get an API key with free trial credits, no card required.
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2
Connect the API
Add our REST or SOAP postcode lookup API to your form using the docs and sample code.
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3
Go live with confidence
Your website now looks up and validates addresses instantly against 30M+ Royal Mail records.
Why Choose This Postcode Web Service
Practical reasons UK businesses choose ePostcode's online postcode lookup software
PAF-certified data
Royal Mail licensed Postcode Address File covering 30M+ UK addresses, updated daily.
Clear, low-cost pricing
Credit packs from 2.2p per search with no setup fees or long contracts.
UK-based support
Technical support direct from the Etellect team that builds and runs the service.
Enterprise-ready
Optional Enterprise SLA with 100% uptime guarantee and dedicated, duplicated infrastructure.
AI & MCP ready
Address lookup for AI tools and agents via a Model Context Protocol (MCP) server.
Trusted since 2006
Two decades of experience powering address lookup for UK businesses and the public sector.
Who Uses Online Postcode Lookup Software?
A postcode web service fits anywhere a UK address needs to be captured
Ecommerce & checkout
Speed up checkout and reduce cart abandonment with instant address autocomplete.
Sign-up & lead forms
Capture clean, deliverable addresses on registration and quote request forms.
Insurance & finance
Validate addresses for KYC, underwriting and policy administration systems.
Public & third sector
G-Cloud 15 listed and used by councils, housing associations and the NHS.
CRM & data teams
Cleanse, de-duplicate and standardise existing customer address databases.
Resellers & agencies
White-label the postcode web service for your own clients and platforms.
Simple, Pay-As-You-Go Pricing
Credit packs for the postcode web service start from just 2.2p per search — no setup fees, no long contracts, and free trial credits to get started.
From 2.2p / search
No setup fees
No long contracts
Free trial credits
Postcode Web Service FAQs
Common questions about our online postcode lookup software
What is a postcode web service?
A postcode web service is a web-based API that lets any website or system look up a full UK address instantly from a postcode, house number or partial address, instead of asking customers to type every line by hand.
What is online postcode lookup software used for?
Online postcode lookup software is used to speed up checkout and sign-up forms, validate UK addresses in real time, reduce failed deliveries, and clean or standardise existing address databases against Royal Mail PAF data.
Is this postcode web service PAF certified?
Yes. The service is built on ePostcode's PAF-certified Royal Mail Postcode Address File, covering over 30 million UK addresses, and is ISO 27001 and ISO 9001 accredited.
How much does the postcode lookup API cost?
Credit packs start from 2.2p per search with no setup fees or long contracts. See full current pricing on epostcode.com.
How do I integrate the postcode web service into my website?
The service is available as a REST and SOAP API with sample code, JavaScript widgets and documentation, so developers can typically add address autocomplete to a form within minutes. Sign up free to get an API key and start testing.