Xero API · Accounting Integration · UK
Xero API Integration.
Custom Xero API integration for UK businesses — automated invoice creation, payment reconciliation, contact sync and financial reporting built directly into your platform. Fixed price. No plugin limitations. You own the code.
Or describe what you need in one line — I’ll reply within one business day.
What it does
What the Xero API provides.
The Xero API provides programmatic access to Xero’s full accounting platform — creating and managing invoices, syncing contacts, applying payments, creating credit notes, managing bank transactions and retrieving financial reports. It supports OAuth 2.0 and can connect to single or multiple Xero organisations.
A custom Xero integration eliminates the manual work of keeping your platform and Xero in sync. Orders become invoices automatically. Stripe or GoCardless payments reconcile against those invoices without anyone touching them. Contacts sync from your CRM. Refunds create credit notes. Financial data flows into your platform’s own reporting interface. The books stay current without manual data entry.
Who it’s for
Who uses a Xero API integration.
Ecommerce businesses on WooCommerce or custom platforms
Every order creates the correct Xero invoice automatically — line items, tax codes and contact details mapped from your platform without any manual bookkeeping. Payments reconcile when they land. Refunds create credit notes. The accounts team sees current, accurate data in Xero without anyone spending time on data entry. For businesses currently exporting CSVs or manually entering orders, the time saving is immediate.
SaaS and subscription platforms
Every subscription payment creates a Xero invoice for that billing period and marks it paid automatically. Failed payments leave the invoice in Awaiting Payment. Cancellations are reflected correctly. The entire subscription billing accounting cycle runs without manual intervention. Combined with Stripe Billing, this means zero manual accounting work for recurring revenue.
Service businesses and agencies
Project invoices generated from your job management, time-tracking or CRM system pushed directly to Xero — no re-keying, no formatting, no late invoices because someone forgot to create them. The integration creates the invoice in your required Xero format, with the correct tracking categories and project codes, the moment the triggering event occurs in your system.
Platforms that need Stripe and Xero connected
Stripe collects the payment. Xero records the invoice. Without a custom integration, someone has to match them manually. With one, Stripe fires a webhook, the integration identifies the Xero invoice, applies the payment, and marks it paid — in seconds, automatically. Refunds create credit notes. Payouts create Xero bank transactions. The entire reconciliation cycle is automated. See the Xero and Stripe integration guide for the full detail.
Accountancy platforms and multi-entity businesses
Multi-organisation Xero connections for platforms serving multiple clients, or businesses managing several entities. Each organisation has its own OAuth connection, its own account mapping and its own token set. The platform creates invoices, syncs contacts and reconciles payments across all connected Xero organisations from a single integration layer.
Why custom
Why a plugin won’t cut it.
Xero plugins for WooCommerce handle simple order-to-invoice sync. They fall short the moment your requirements go beyond a single VAT rate and a standard WooCommerce setup.
Correct tax handling
Multiple VAT rates, reverse charge, zero rating, OSS registrations — plugins apply basic tax mapping. Custom integrations handle your actual tax requirements correctly from the start.
Automatic reconciliation
Stripe or GoCardless payments matched to Xero invoices automatically via webhooks. Plugins don’t handle payment reconciliation. Custom integrations do.
Multi-organisation
Managing multiple Xero organisations from one platform always requires a custom build. No plugin handles multi-tenant Xero connections.
No third-party dependency
You own the code. No ongoing SaaS fees, no vendor lock-in, no waiting on a plugin update when WooCommerce releases a major version change.
The process
How a Xero API integration is built.
Scoped before anything is built. Fixed price agreed in writing. Tested in Xero sandbox before going live.
Scoping
We map your invoice structure, contact data, tax treatment, payment flows, Xero account codes and any tracking categories or project codes. Tax handling and account mapping are agreed explicitly before development starts.
Fixed-price quote
Clear, itemised quote before work begins. Scope agreed in writing. No surprises mid-project.
Xero OAuth setup
Xero app registration, OAuth 2.0 connection flow, token storage (encrypted) and automatic token refresh configured. Single or multi-organisation as required.
Build and integration
Invoice creation, contact sync, payment reconciliation, credit notes, Xero data retrieval and any reporting endpoints built and integrated with your platform to specification.
Testing and handover
Full testing in Xero sandbox across invoice types, VAT scenarios, payment events, refunds and edge cases. Complete technical documentation covering the integration architecture and how to extend it.
The deliverable
What’s included.
What I build
- Xero OAuth 2.0 authentication with encrypted token storage and automatic refresh
- Invoice and credit note creation from your platform events
- Contact creation and sync from your CRM or database
- Payment creation and invoice reconciliation (Stripe, GoCardless or bank)
- Correct VAT mapping to your Xero tax rates and account codes
- Tracking category and project code application
- Duplicate prevention and idempotency handling
- Error logging, failed sync alerts and retry logic
- Technical handover document
What’s not included
- Xero subscription — you need an active Xero account (developer demo company available for testing)
- Xero app registration — done by you, takes 10 minutes, free
- Accountancy or tax advice — account code and tax mapping agreed with your accountant, implemented by me
- Xero Payroll — separate Xero product, not covered by the standard API
- Changes to your existing platform outside the integration scope
Pricing
Fixed-price builds. No hidden costs.
Every build is scoped and quoted at a fixed price. Xero’s API is free to use beyond your standard Xero subscription.
Invoice Sync
£1,295
~1–2 weeks
Automated invoice creation and contact sync. Orders or events in your platform create correctly structured Xero invoices automatically — right VAT codes, right accounts, right contact. Credit notes for refunds. Best suited to service businesses, agencies and B2B platforms where payment arrives separately by bank transfer or Direct Debit mandate — the invoice is raised automatically, payment reconciled via Xero’s bank feed or the Full Reconciliation tier.
- OAuth 2.0 with encrypted token storage
- Invoice creation from your platform events
- Contact creation and deduplication
- Correct VAT and account code mapping
- Credit notes for refunds
- Error handling and sync alerts
- Payment reconciliation
- Multi-organisation
Full Reconciliation
£1,995
~2 weeks
Everything in Invoice Sync, plus automatic payment reconciliation. Stripe or GoCardless payments matched to Xero invoices and applied automatically via webhooks. Payout reconciliation creating Xero bank transactions. The full invoice lifecycle — created, paid, credited or voided — managed automatically by your platform.
- Everything in Invoice Sync
- Stripe or GoCardless payment reconciliation
- Webhook-driven invoice lifecycle management
- Payout bank transaction creation
- Failed payment handling
- Audit log of all reconciliation operations
Multi-Organisation
£2,995
~3–4 weeks
Full Reconciliation build for platforms connecting to multiple Xero organisations. Separate OAuth connections, token management and account mapping per organisation. For accountancy platforms, multi-entity businesses and any platform providing Xero functionality to multiple clients.
- Everything in Full Reconciliation
- Per-organisation OAuth and token management
- Configurable account mapping per organisation
- Organisation admin and connection management UI
- Multi-tenant error handling and alerting
- Technical handover document
Payment terms: 50% on agreement, balance on completion before handover. Xero app registration is free and takes approximately 10 minutes through the Xero developer portal.
Common questions
Xero API FAQ.
Does the Xero API require an active Xero subscription?
Yes — the organisation you’re connecting to needs an active Xero subscription. Xero provides a free demo company in every account for development and testing, so the integration can be fully tested without affecting your live Xero data.
How does Xero OAuth 2.0 work?
Xero uses OAuth 2.0 — a user authorises your application to access their Xero organisation, and your app receives access and refresh tokens. Access tokens last 30 minutes and refresh automatically. Both tokens are stored encrypted in your database. The integration handles token refresh transparently — the connection stays live as long as the integration runs.
Can it handle VAT correctly for my business?
Yes — VAT mapping is a key part of the scoping and build process. Standard rate, zero rate, exempt, reduced rate, reverse charge and no-supply treatments are all handled. The mapping is agreed explicitly before development starts, often in consultation with your accountant, and tested thoroughly before going live.
Can it connect to multiple Xero organisations?
Yes — the Multi-Organisation tier handles this. Each organisation has its own OAuth connection, token storage and account mapping configuration. This is relevant for accountancy platforms managing multiple clients, and for businesses with multiple trading entities each in their own Xero organisation.
Can it reconcile Stripe payments with Xero automatically?
Yes — this is the Full Reconciliation tier. Stripe webhook events trigger automatic payment application to the matching Xero invoice. Refunds create credit notes. Stripe payouts create Xero bank transactions. The full reconciliation cycle runs automatically. See the Xero and Stripe integration guide for the full detail.
What about GoCardless and Xero?
GoCardless Direct Debit payments can also be reconciled with Xero automatically. GoCardless has a multi-state payment lifecycle (pending, confirmed, paid) and the integration handles this correctly — applying the payment to the Xero invoice when it’s confirmed, not when it’s first created.
How long does a Xero integration take?
Invoice Sync takes approximately one to two weeks. Full Reconciliation takes approximately two weeks. Multi-Organisation takes three to four weeks. Timeline starts once scope is agreed and the deposit is paid.
Can it work with WooCommerce?
Yes — WooCommerce integration is one of the most common Xero builds. Orders sync as invoices on status change, contacts are created or updated, and payments from WooCommerce’s payment gateways are reconciled in Xero. See the Xero WooCommerce integration guide for how it works.
A Xero integration is a common addition to the custom websites I build in Blackburn, working alongside SEO and content support to keep new business flowing in.
Need Xero API integration built?
Describe your platform, your invoice structure and what you currently do manually — I’ll come back with a straight answer on what’s involved and what it costs. Fixed price, no obligation.
