Step-by-step Xero API integration: OAuth 2.0, tenant routing, paging, rate limits, the 2026 scope and pricing changes, plus a no-code path to PostgreSQL.
By Ilshaad Kheerdali · 4 August 2026
The Xero API is well documented and pleasant to work with once it clicks, but the first integration always takes longer than people expect. There is an extra discovery step that most accounting APIs don't have, tokens expire faster than you'd guess, and 2026 brought two changes that alter how you scope and budget an integration.
This guide walks the whole flow: creating an app, running OAuth 2.0, resolving which organisation you're actually talking to, making your first call, paging through results, staying inside the rate limits, and pulling incremental updates. At the end it covers what changed in 2026 and the shortcut if the plumbing isn't the part you want to own.
Everything below targets the Xero Accounting API over OAuth 2.0. Xero retired OAuth 1.0a some years ago, so any tutorial you find that mentions consumer keys and signed requests is out of date.
