Create or update multiple accounting vendors
Allows for the creation or updating of multiple vendors in a single request. Maximum 100 vendors per request.
Vendors are saved one by one. If some fail, the others are still saved: the response lists the failed ones in failures and counts them in fail_count. If every vendor fails, the response is a 400 with code VEN4000, and message holds the same object with success_count 0 and the reasons in failures.
Deprecation notice: This synchronous endpoint is deprecated for high-volume use. Use POST /vendors/bulk-async instead — it avoids request timeouts on large batches and provides progress tracking via the batch polling API. This endpoint remains fully supported for existing integrations.
Authentication
Headers
API version to use (optional, defaults to latest). Supported values: 1.0.0, 1.1.0.
Client-generated unique key (UUID/ULID recommended). JSON requests: the first 2xx response is cached for 24h and replayed on a same-key retry with a matching body; a different body returns 422. Non-JSON requests (e.g. file uploads): the key is single-use — any same-key retry returns 422 regardless of body. See Idempotency for full details.
Request
Response
(Beta — this field is available in sandbox and not yet in production.)
(Beta — this field is available in sandbox and not yet in production.)

