What Intuit documents for integration builders
Every object carries a SyncToken that changes whenever it is modified, and an update must present the current one; a mismatch is the Stale Object Error. A request id on a create call returns the original response on a repeat, but Intuit does not publish how long an id is remembered. The REST API throttles at 500 requests a minute per company and 10 requests a second per company and app, returns 429 and advises waiting 60 seconds. A customer's display name must be unique across customers, vendors and employees together. Multicurrency can only be switched on in the product and cannot be switched off. Intuit describes a sandbox company as a QuickBooks Online company with sample data for development and testing.
Failure families and where to go next
Updates that fail intermittently, duplicate invoices after a retry, lines posting to the wrong account and foreign invoices with the wrong rate are separate problems. Each has a guide with the mechanism and a safe first investigation; some also have a bounded paid job.
- Stale updates: the SyncToken guide and the stale-object job.
- Duplicate invoices: the request-key guide and the retry-safety job.
- Wrong accounts: the mapping-table guide and its fixed-price job.
- Wrong rate direction: the currency guide; QuickBooks expresses rates home-per-foreign, the opposite of Xero.
- Duplicate Name Exists errors are a separate customer-naming problem; we do not currently list a QuickBooks customer job.
A safe test looks like this
Use a sandbox company, never live invoices. Keep invented data, record counts and the error text with names removed, and do not assume the sandbox reproduces every production behaviour; the handover of any job lists what the sandbox could not prove and asks your account holder to verify one live change under their own control.
Choose the actual outcome
One known failure is a bounded job; several interacting failures are a project; watching a sync over time is a standing service. None includes bookkeeping, tax or audit advice, or changes to posted or locked records. Prices on the linked pages are untested published prices and nothing starts without written agreement.
- The first enquiry uses invented examples, not credentials, invoices or customer records.
- Real records are shared only after agreement, through a secure handoff.
Sources and limits
- Intuit: error 5010, Stale Object Error Checked 2026-10-11.
- The error means the update did not use the latest version of the object, which is carried in its SyncToken.
- Intuit recommends either storing each object's identifier, type and SyncToken and refreshing them from change data capture or webhooks, or reading the object before every update.
- Intuit: what is RequestId Checked 2026-10-11.
- A request id passed as a query parameter makes a repeat of the same request return the original response instead of repeating the operation.
- The id may be up to 50 characters for non-batch operations and must be unique across requests for a company.
- Intuit: API call limits and throttles Checked 2026-10-11.
- The QuickBooks Online REST API allows 500 requests per minute per company and 10 requests per second per company and app, and returns HTTP 429, advising a wait of 60 seconds.
- Batch requests are suggested at up to 30 payloads, with throttling from 40 batch requests per minute per company and app; a query returns at most 1,000 entities.
- Intuit: error 6240, Duplicate Name Exists Checked 2026-10-11.
- A customer's DisplayName must be unique across all customers, vendors and employees in the company.
- Intuit suggests keeping a store of identifiers and display names to check before creating a record, kept current with change data capture and webhooks.
- Intuit: manage multiple currencies Checked 2026-10-11.
- Multicurrency can only be enabled in the QuickBooks Online product, not through the API, and cannot be disabled once enabled.
- Exchange rates are recorded as the number of home-currency units that equal one foreign-currency unit.
- Intuit: create and test with a sandbox company Checked 2026-10-11.
- A sandbox company is a regionally specific QuickBooks Online company with sample data, provided for development and for non-commercial testing.