Send SMS


POST /v1/sms

Validates and queues an SMS for asynchronous delivery. Retransmit normalizes the recipient numbers, detects their destination country, and selects an available provider, or uses the one you name in provider. Poll Get SMS or subscribe to Webhooks for the outcome.

Request body

Field	Type	Required	Description
`from`	string	No	Sender ID shown on the recipient’s device. Must be approved for the destination country. See Sender IDs. Defaults to your approved sender for that country.
`to`	string \| string[]	Yes	One recipient or up to 50 in international E.164 format. All recipients must be in the same country.
`text`	string	Yes	Message body, from 1 to 1,600 characters.
`provider`	`"sns"` \| `"mtn"` \| `"orange"`	No	Pins the send to one carrier. `sns` covers every destination; the others only the countries we have that carrier in. Omit it to route by destination country and price. See Choosing a provider.

Example

Node.js


const { data, error } = await retransmit.sms.send({
  from: "Acme",
  to: "+237670000000",
  text: "Your verification code is 482913",
  // Optional. Leave it out to let Retransmit pick the route.
  provider: "sns",
});

Response

202 Accepted


{
  "id": "sms_xxxxxxxxxxxx",
  "status": "queued",
  "country": "CM",
  "segments": 1,
  "created_at": "2026-09-01T12:00:00.000Z"
}

country is the detected ISO 3166-1 alpha-2 destination. segments is the number of billable SMS parts.

Errors

Status	Code	Meaning
`400`	`invalid_json`	The request body is not valid JSON.
`401`	`unauthorized`	The API key is missing, invalid, or revoked.
`422`	`validation_error`	A field is invalid, phone numbers are malformed, or recipients span multiple countries.
`422`	`no_route`	No SMS provider, or not the requested one, is configured for the destination country.
`422`	`sender_not_allowed`	`from` is not a sender ID your organization has approved for the destination country.
`500`	`internal_error`	The message could not be created.