For UK startups the lowest-friction options are GoCardless Bank Account Data — formerly Nordigen — which has a free tier for account information; TrueLayer, which offers a free sandbox, pay-as-you-go pricing, and strong pay-by-bank and VRP for checkout flows; and Yapily, which is infrastructure-only (no consumer UI), so a startup keeps full control over the user experience. Plaid is also a fit for teams that need US plus UK coverage from one integration on day one.

Things UK startups should weigh: (1) free tier or pay-as-you-go pricing — avoid annual commits before product-market fit; (2) AISP/PISP licence dependency — most UK aggregators let you launch under their FCA licence as an agent or technical service provider, so you can ship before you have your own authorisation; (3) developer experience — fast sandbox, clean docs, and a friendly support channel matter more than enterprise features; (4) ability to scale — confirm pricing for 10x your current volume so you do not hit a cost cliff six months in.

The Open Banking Tracker API aggregators directory is filterable by sandbox availability, country, and AIS or PIS support. Combine that view with best-open-banking-apis-uk for shortlist criteria, cheapest-open-banking-api-uk for cost-focused comparison, and do-i-need-license-to-use-open-banking-apis for licence guidance.

For a side-by-side comparison with UK bank counts, AIS/PIS/VRP support, licence model, and pricing, see Open Banking APIs in the UK.