Ready to try Postcoder?
Join over 10,000 organisations using Postcoder to capture better data and deliver better experiences. Start your free 30-day trial today - no credit card required.
Capture accurate, validated data from the start to keep your records clean, consistent and trustworthy.

Most organisations know their data isn't perfect. What's less obvious is how much time is spent working around it. And it's tiresome work too, like reports that need manual sense-checking before they're shared or contact lists that must be cleaned before every campaign. The problem isn't just the bad data; it's the ongoing overhead of managing the consequences.
So how can we fix this? The most effective place to tackle bad data is at the point of entry, before it reaches your database at all.
Address fields that accept free text produce inconsistent, unstructured records that are hard to deduplicate or match
Email and mobile details that go unvalidated at sign-up become unreachable contacts over time
Manual data entry introduces errors that compound as records are copied between systems
Maintaining your own address data, such as a PAF file, creates an ongoing overhead that quickly falls out of date
Postcoder validates and structures contact data at the point of capture, so clean records enter your systems from the start.
Address lookup returns data in a consistent format every time: the same fields, the same structure, regardless of how a customer or user types their query. There is no variation to reconcile later. Email validation confirms addresses are real and deliverable. Mobile validation checks that numbers are active on a network. And because Postcoder connects directly to Royal Mail's PAF data and the Ordnance Survey's National Geographic Database, updated daily, you're always working from current, authoritative source data rather than a local copy you're forced to maintain yourself.
The result is a database that stays accurate over time, with less manual effort to keep it that way.
Postcoder is a multi-feature API you can integrate into your website or app quickly and easily using pre-built integrations, sample code and API reference, all within clear and well-structured docs. You can be up and running in minutes with a free trial, and Postcoder's support specialists are always on hand if you need help.
Return validated, structured address data in a consistent format every time. Datasets updated daily for up-to-the-minute addresses and UPRN records. No free-text variation, no formatting inconsistencies, no manual correction.
Learn more about address lookupConfirm that email addresses are valid and deliverable at the point of entry. Catch typos, disposable addresses and inactive domains before they reach your database.
Learn more about email validationCheck that mobile numbers are real, correctly formatted and active on a network. Reduce the number of unreachable contacts in your records over time.
Learn more about mobile validationValidates sort codes and account numbers against the published modulus checking rules, confirming that bank details are correctly formatted and matched before they are stored. Essential for paperless direct debits.
Learn more about bank validation
"It ensures that the addresses our customers enter are correct and standardised. This has drastically cut down on errors and improved our customer satisfaction."
Niamh K. Head of Marketing and Digital Transformation / G2 review
"Postcoder supports both our internal and external user experience by enabling fast and accurate address entry. This speeds up data input and ensures consistent, verified data, which is essential for reliable reporting and operational accuracy."
Theodore W. Senior Product Manager / G2 review
"We were using the PAF file from Royal Mail. Trying to keep it up to date within our own custom CRM system was causing some issues. Postcoder has solved that issue; no more having to update the PAF files."
Anthony S. IT Manager / G2 review
"[Postcoder is] solving the problem where we need to have the latest accurate postal information from Royal Mail for DBS checks. Without this, we cannot accurately submit applications."
Craig F. Employment Vetting Manager / G2 review
Businesses rate Postcoder 4.7 stars out of 5 on the world's most trusted software marketplace.

Join over 10,000 organisations using Postcoder to capture better data and deliver better experiences. Start your free 30-day trial today - no credit card required.