Money movement - Tesouro

Tesouro exposes four payment rails. Pick the rail by use case: internal sweep, same-day settlement, real-time receipt, or cross-bank push. Each has different speed, availability, limits, and reversibility characteristics.

Every rail accepts an idempotencyKey, and you should treat it as required in production. It is the only protection against duplicate transfers when a request times out or is retried. See Lifecycle & idempotency.

Rail comparison

Rail	Speed	Direction	Availability	Max per transfer
Internal	Instant	Internal only	24/7	No service cap
ACH	One to three business days	Send and receive	Business days	Set by bank
RTP	Seconds, irrevocable	Send and receive	24/7/365	$10M (TCH)
FedNow	Seconds, irrevocable	Send and receive	24/7/365	$10M (Fed)

Prerequisites

Prerequisite	Notes
Internal account	An open, funded deposit account opened through the onboarding flow.
External account	A pre-linked external account (see Linked accounts) for ACH.
Authentication	A bearer token with `embedded:transfer:write`. ACH, RTP, and FedNow additionally need their per-rail scope.
Org rail configuration	The caller’s organization must have the rail enabled (managed in the Profile service). A rail that isn’t enabled returns `403`.

Next steps

Linked accounts — how to link external accounts before ACH push/pull works.
Authentication — scope wiring and token issuance.