Bulk SMS

POST

Send the same or customized SMS messages to multiple recipients in a single request. Supports up to 100 recipients per call with per-recipient message overrides.

Endpoint

POST

https://api.smsgateway.com/api/v1/sms/bulk

Request Headers

Header	Required	Description
Authorization	Required	Bearer token API key.
Content-Type	Required	`application/json`

Request Body

Parameter	Type	Required	Description
body	string	Required	Default message body sent to all recipients unless overridden. Max 1,600 characters.
recipients	array	Required	Array of 1–100 recipient objects.
recipients[].to	string	Required	Recipient phone in E.164 format.
recipients[].body	string	Optional	Per-recipient message override. If omitted, the default `body` is used.
senderId	string	Optional	Approved sender ID, max 15 characters.
idempotencyKey	string	Optional	Prevents duplicate bulk sends within 24 hours.

Examples

Bulk SMS with cURL

1curl -X POST https://api.smsgateway.com/api/v1/sms/bulk \
2  -H "Authorization: Bearer sg_live_xxxxxxxxxxxx" \
3  -H "Content-Type: application/json" \
4  -d '{
5    "body": "Your appointment is tomorrow at 10:00 AM.",
6    "recipients": [
7      { "to": "+251911234567" },
8      { "to": "+251922345678" },
9      { "to": "+251933456789", "body": "Hi! Your appointment is at 11:00 AM." }
10    ],
11    "senderId": "ClinicApp"
12  }'

Response

Success (201 Created)

Success response

1{
2  "success": true,
3  "data": {
4    "batchId": "batch_9k3j4h5g6d",
5    "totalRecipients": 3,
6    "totalSegments": 3,
7    "totalCost": 0.06,
8    "results": [
9      {
10        "messageId": "msg_a1b2c3d4e5",
11        "to": "+251911234567",
12        "status": "QUEUED",
13        "segments": 1,
14        "cost": 0.02
15      },
16      {
17        "messageId": "msg_f6g7h8i9j0",
18        "to": "+251922345678",
19        "status": "QUEUED",
20        "segments": 1,
21        "cost": 0.02
22      },
23      {
24        "messageId": "msg_k1l2m3n4o5",
25        "to": "+251933456789",
26        "status": "QUEUED",
27        "segments": 1,
28        "cost": 0.02
29      }
30    ]
31  }
32}

Cost

Bulk SMS is charged per recipient, not per request. The cost per message depends on the destination country and message segments. Check the totalCost field in the response for the exact charge.

Rate Limits

10 requests per minute

Per organization. Due to the high volume of messages per request, the bulk endpoint has a lower rate limit than the single send endpoint.