
Ideal postcodes
Fetchify
Loqate
Data8 UK
Data8 UK PredictiveAddress
Email Verification API
Google Maps API
Fast UK address, email & phone validation APIs for developers. Official Royal Mail PAF data. Pay as you go, 100 free lookups.
Smarty
Zipcodestack
PostalDataPI
Geoco.io
Melissa Data Quality
Loqate
usZIPCodes.org
REST API for US ZIP, ZIP+4, and Canadian postal codes. Single unified endpoint covers address validation and standardization, radius search (centroid haversine and true spatial polygon intersection), point-to-point distance, autocomplete/typeah

Which is more popular?
Website, pricing, platforms and company facts side by side.
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ZIP
ZIP Code API
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| Website | postio.co.uk | zip-codes.com |
| Pricing | — | |
| Platforms | — | |
| Company | Startup from the United Kingdom · 1 - 9 employees | Startup from the United States · 2026 |
| Listed in |
In their own words, as submitted to SaaSHub.

Postio (postio.co.uk) is a developer-focused data validation platform providing real-time UK address lookup, email verification, and phone validation via plain REST APIs and drop-in SDKs. As an official Royal Mail PAF Solutions Provider, Postio synchronises 30M+ UK addresses daily for accurate...
API for US ZIP, ZIP+4, and Canadian postal code data. One unified endpoint set covers North America — no separate APIs by country or data type. What it does Address validation and standardization — production-grade parser with ZIP+4 append, refreshed monthly Radius search — centroid haversine and...
What each product offers, as listed by its team.

An editorial look at what each product does well and who it suits.

No analysis of Postio.co.uk yet.
Overall verdict
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How often each product is chosen within a category, 0–100% relative to the other.

As answered by people managing Postio.co.uk and ZIP Code API.
Postio.co.uk's answer
Postio charges only when a lookup returns a result — searching is free. Address, email and phone validation sit behind one API with a single JSON response envelope, so you integrate once rather than stitching three vendors together. Address data comes from Royal Mail's Postcode Address File under a direct licence, not scraped or resold sources. There are no tiers, contracts or minimum spend, and the first 100 lookups need no card.
Postio.co.uk's answer
A REST API served from edge locations, with official SDKs for JavaScript/Node, Python, Go, PHP, Ruby and .NET, all open source on GitHub. The API is documented by a public OpenAPI specification.
Postio.co.uk's answer
Pricing is published and pay-as-you-go: 2.2p per address, 1p per email, 1p per phone, billed only on a result. No sales call, no annual contract, no minimum commitment. You can be live in a few minutes with 100 free lookups and no card, and the same API covers all three validation types. For UK addresses specifically, the data is licensed directly from Royal Mail rather than obtained second-hand — which matters after the 2025 High Court ruling on database rights in this market.
Postio.co.uk's answer
Developers and technical teams building UK-facing forms — ecommerce checkouts, signup flows, CRM and logistics systems. Typically small to mid-sized product teams, agencies building for UK clients, and software vendors embedding address lookup in their own product. It suits anyone who wants a UK-accurate API without an enterprise procurement process.
Postio.co.uk's answer
Postio is a trading name of Onno Group Limited, registered in England & Wales (company no. 08622799). It was built to make Royal Mail PAF-accurate UK validation available on straightforward pay-as-you-go pricing, rather than the contracts and minimum commitments that have been standard in this market. Address, email and phone validation were brought together behind one consistent API so a team can solve all three at once.
Postio.co.uk's answer
Serving a huge range of customers across the world looking for a blazing fast UK Address AIP product. From bootsrapped entrepreuners to FTSE 250 companies. We serve them all.
Share your experience with using Postio.co.uk and ZIP Code API. For example, how are they different and which one is better?
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Fetchify delivers fast, accurate address, email, phone and bank validation tools that help businesses capture clean, verified customer data, reduce failed deliveries and improve checkout experiences worldwide.
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Free Zip Code API - Free Postal Code Validation | Zipcodestack
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The most affordable postal code API. 240+ countries, sub-5 ms responses. Simple, elegant, transparent.
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