curl --request POST \
--url https://api.slash.com/transfers/book-transfer \
--header 'Content-Type: application/json' \
--header 'X-API-Key: <api-key>' \
--header 'X-Idempotency-Key: <x-idempotency-key>' \
--data '
{
"from": "<string>",
"to": "<string>",
"amountCents": 123,
"memo": "<string>"
}
'{
"transferId": "<string>"
}Create book transfer
Initiate a book transfer — an instant, intra‐Slash money movement between two accounts the caller has access to.
from and to accept any Slash account id the caller can address:
sa_group_*— a Slash account group’s primary cash accountsub_*— a virtual account inside a Slash account group
The legal entity owning from must equal the request’s x-legal-entity
header (the source-scope guard for user-scoped API keys), and the caller
must be a member of both from and to’s legal entities. Cross-legal-
entity transfers between entities you own are supported; sending to a
third party is not (see closed-loop-payment, coming soon).
Payment is settled instantly on Slash’s ledger — no banking-network rail is touched. For ACH/wire/RTP, use the rail-specific endpoint.
curl --request POST \
--url https://api.slash.com/transfers/book-transfer \
--header 'Content-Type: application/json' \
--header 'X-API-Key: <api-key>' \
--header 'X-Idempotency-Key: <x-idempotency-key>' \
--data '
{
"from": "<string>",
"to": "<string>",
"amountCents": 123,
"memo": "<string>"
}
'{
"transferId": "<string>"
}Authorizations
API key authentication for public API requests.
Keys come in two flavors:
- Legal-entity-scoped keys are pinned to a single legal entity. Minted via the dashboard under a specific entity; every request acts on that entity.
- User-scoped keys are pinned to a user and span every legal
entity that user has access to. Every request made with a
user-scoped key (except
GET /legal-entity, which lists the legal entities the user can access) must include anx-legal-entityheader naming the legal entity the request is operating on. Requests without the header are rejected with400. The authenticated user must have an active permission role on the supplied legal entity, otherwise the request is rejected with403.
Headers
Unique key to ensure idempotency of the transfer.
Body
Response
OK
The ID of the transfer that was created.