External Accounts

Register a customer’s own bank account (an “external account”) to enable fiat withdrawals. The endpoint accepts US_FEDWIRE, US_ACH, US_RTP, SWIFT, SPEI, LOCAL_BANK_TRANSFER, CHATS, and FPS; availability depends on the account country, currency, and enabled payment routes. A unique external_account_id is assigned on success.

HTTP Request

POST
https://api.sandbox.1money.com/v1/customers/{customer_id}/external-accounts

Path Parameters

Parameter	Type	Description
`customer_id`	string	UUID of the customer that will own the external account

Headers

Header	Description
`Authorization`	Sandbox bearer token or production HMAC authorization (required; see Authentication)
`X-OM-Date`	Request timestamp required for production HMAC authentication; omit for sandbox bearer authentication
`Content-Type`	`application/json` (required)
`Idempotency-Key`	UUIDv4 required for this request

The create endpoint returns 409 Conflict when the idempotency key already belongs to an external account or when identical banking details already exist. You can retrieve an existing external account by sending the key as the idempotency_key query parameter to the GET endpoint.

Request Body

{
  "network": "US_FEDWIRE",
  "account_holder_name": "TechStart Holdings LLC",
  "currency": "USD",
  "country_code": "USA",
  "account_number": "4447891623",
  "institution_id": "021000021",
  "institution_name": "JPMorgan Chase Bank, N.A."
}

Field	Type	Required	Description
`network`	string	Yes	Payment network accepted by the request schema; route availability depends on country and currency
`account_holder_name`	string	Yes	Full legal name registered with the bank
`currency`	string	Yes	Currency code (e.g. `USD`)
`country_code`	string	Yes	ISO 3166-1 alpha-3 country code
`account_number`	string	Yes	Account number or rail-specific account identifier
`institution_id`	string	Conditional	Required for every listed network except `SPEI`; omit it for `SPEI`
`institution_name`	string	No	Optional institution name; supported routing-code networks can resolve it from `institution_id`

Additional fields might be required:

institution_clearing_code: Additional local or regional routing codes required by specific payment networks or countries. Examples: Sort codes (UK), BSB numbers (Australia), transit numbers (Canada). Optional field used when standard institution_id is insufficient for routing.
intermediary_bank: Optional intermediary bank information for SWIFT accounts. Omit this field for all other networks.
nickname: Can be used to present to the user for easier identification

Rail-specific routing fields

External accounts and recipient bank accounts use the same rail-specific routing rules.

Network	`institution_id`	`institution_name`	`intermediary_bank`
`US_ACH`, `US_FEDWIRE`, `US_RTP`	Required: valid 9-digit ABA routing number	Optional; resolved from the ABA routing number when omitted	Must be omitted
`SWIFT`	Required: valid 8- or 11-character SWIFT/BIC code	Optional; resolved from the SWIFT/BIC code when omitted	Optional
`SPEI`	Must be omitted; the 18-digit CLABE identifies the bank	Not required	Must be omitted
`LOCAL_BANK_TRANSFER`	Required: canonical institution ID for the destination country and currency	Not required	Must be omitted
`CHATS`	Required: Hong Kong bank SWIFT/BIC code	Optional; resolved from the SWIFT/BIC code when omitted	Must be omitted
`FPS`	Required: canonical three-digit Hong Kong bank clearing code for the destination currency	Not required	Must be omitted

CHATS applies to Hong Kong USD accounts. FPS applies to Hong Kong HKD and CNY accounts; submit the branch code followed by the account number as account_number (9–16 digits in total). Select the canonical institution_id for LOCAL_BANK_TRANSFER or FPS from Local Institution ID. Omit institution_clearing_code for SPEI, LOCAL_BANK_TRANSFER, CHATS, and FPS.

The API schema may contain additional bank-network enum values. That does not mean every rail is enabled for every customer or in every environment. Availability depends on the destination country, currency, customer configuration, and active payment routes.

PIX_TRANSFER may appear in the shared network enum, but it is not supported when creating an external account or recipient bank account through these public endpoints. Do not submit institution_id for PIX; PIX uses PIX-specific identifiers through a separate integration flow.

Responses

Status	Description
201 Created	External account successfully created; returns `external_account_id`
400 Bad Request	Invalid or missing fields
409 Conflict	Duplicate idempotency key or identical banking details