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SET DocsAPI reference and complianceUpdated 2026-11-08
Browse: SET API (Platforms)

SET API (Platforms) · Customers

Create a customer

POST/v1/customers

Key scope: write · Success: 201

Names a merchant (or individual) and starts its verification. In production the answer carries the hosted terms link (tosLink) and KYB/KYC link (kycLink) the customer completes. One customer per externalId: a repeat returns the existing one.

Headers

Idempotency-Key string
Optional. The same key and body run once; a replay answers with Idempotent-Replayed: true. Kept 24 hours.

Body

externalId stringrequired
Your id for the customer: 1–64 of A-Z a-z 0-9 _ . : -.
type "business" | "individual"required
KYB for a business, KYC for an individual.
name stringrequired
Exact legal name.
email stringrequired
Where the verification links are tied. Sent to the verification provider only; SET does not store it.
endorsements string[]
Any of base (USD), sepa (EUR), faster_payments (GBP) to request on the first link.
redirectUri string
HTTPS URL the customer returns to after the hosted pages.

Notes

  • In staging the customer is synthetic: approve it with POST /v1/sandbox/customers/{id}/approve (the sandbox cannot complete a hosted link).

Errors

  • 400 external_id_invalid
  • 400 type_invalid
  • 400 name_invalid
  • 400 email_invalid
  • 400 endorsements_invalid
  • 400 redirect_uri_invalid
  • 409 customer_type_conflict
  • 409 email_already_onboarded
  • 401 api_key_required
  • 401 api_key_invalid
  • 401 api_key_wrong_mode
  • 403 scope_missing
  • 429 rate_limited

All codes: Errors.