Sync data with FreeAgent
Unified. Reliable. Secure.
FreeAgent is a cloud accounting platform built specifically for the UK market, used by freelancers, contractors, and small businesses as well as the accounting firms that serve them. The platform covers invoicing, expenses, bank reconciliation, payroll, and UK-specific tax workflows including Making Tax Digital (MTD) VAT filing, Self Assessment, and Corporation Tax returns.
Integrate FreeAgent alongside dozens of other accounting and ERP systems through Maesn Unified API.
Token Refresh Rate-Limited to 15 Per Minute — Managed Across All Your Tenants
FreeAgent caps token refreshes at 15 per minute, which can cause failures in multi-tenant syncs running concurrently. Maesn manages the full token lifecycle with rate-limit-aware refresh scheduling — no 429s on the token endpoint, no re-authorization surprises.
Pagination via Link Headers — 25 Results Default, Complete Data via Maesn
FreeAgent defaults to 25 results per page and exposes pagination through response headers rather than the JSON body. Maesn paginates all endpoints automatically and parses Link headers under the hood — you always receive the complete dataset.
Numeric Access Levels and Dual API Model — Handled Without Extra Complexity
FreeAgent controls access via a numeric level system (0–8) rather than named scopes, and has two separate API products for companies and accounting practices. Maesn configures the correct access level and routes API products under a single integration — no separate app registrations or logic paths required.
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Why companies choose Maesn
3 Reasons Why It Is Better To Integrate FreeAgent API With Maesn
Secure & Compliant
We have a strong relationship to FreeAgent. This ensures that the Maesn API is always up-to-date and any maintenance is covered on our end.
Common Data Model
We provide a clean, unified data model that abstracts away system-specific quirks, so teams can build reliable integrations without dealing with ERP-specific complexity or workaround-heavy implementations.
FreeAgent Sandbox
We provide you with everything you need, so you can focus on what counts.
FreeAgent is a UK-focused cloud accounting platform for freelancers, contractors, small businesses, and accounting firms. It is HMRC-recognised software for Making Tax Digital (MTD) VAT filing and supports Self Assessment, Corporation Tax, payroll, and CIS reporting — making it one of the most comprehensive UK-specific accounting platforms available.
The main challenges are: configuring the correct numeric access level for your app; handling two separate API products for direct users and accounting practices; managing OAuth token refresh within the 15-per-minute rate limit; parsing Link response headers for pagination instead of a JSON metadata object; and implementing back-off logic for the 120 requests per minute rate limit.
A direct integration requires configuring numeric access levels, managing token refresh rate limits across tenants, parsing Link headers for pagination, and handling strict per-user rate limits with back-off logic — all before shipping your first feature. Maesn handles all of this through a single unified API.
The Company API is for direct FreeAgent users — freelancers and businesses managing their own accounts. The Accountancy Practice API is for accounting firms managing multiple client accounts through FreeAgent's Practice Dashboard. They require separate app registrations, different OAuth flows, and different header configurations. Rate limits also apply differently: per user for the Company API, and per client subdomain for the Practice API.
FreeAgent enforces a cap of 15 token refreshes per minute per user. This is manageable for single-tenant integrations but can cause 429 errors in multi-tenant SaaS products that refresh tokens concurrently across many customers at the same time — for example during a scheduled sync.
Yes. Maesn maps FreeAgent's UK-specific tax data — including VAT returns, Self Assessment, and Corporation Tax data — into its common data model. Check the Maesn documentation for FreeAgent for current endpoint coverage.
Frequently Asked Questions About FreeAgent API Integration
