SMS API

A plain REST API for sending SMS

POST your sender, recipient and content with a Token header. Get a message ID straight back, and delivery reports pushed to your server.

Start free Read the docs

Send your first SMS

One request, one message

Authenticate with your access key, POST the message, and read the msgid from the response. Press the button to see it run.

1curl -X POST https://secure.smslocal.com/api/service/enterprise-service/external/sms \
2  -H "Token: $SMSLOCAL_TOKEN" \
3  -H "Content-Type: application/json" \
4  -d '{
5    "from": "SMSLOCAL",
6    "to": "14155550123",
7    "content": "Your code is 481920."
8  }'

POST /external/sms

POST/external/sms

Response

Run the request to see the response.

Built for developers

Nothing exotic to learn

Three ideas cover the whole API, which follows plain REST conventions.

01Authentication
Token authentication
Send your access key in a Token header on every request, with JSON in and JSON out.
- No SDK required
- Works from any language
- Keep the key in an environment variable
02Response
Know it was accepted
Every send returns a msgid and an errorcode immediately.
- Store the msgid against your own record
- errorcode 0 means accepted
- Use the msgid to match reports later
03Replies
Two-way by default
Replies arrive on the same callback, marked as mobile originated.
- Same message shape as reports
- Tell directions apart with mt / mo
- Route replies to your support tools

Delivery reports

See what happened to every message

A status report is posted to your callback URL when a message reaches its final state.

1
Match by msgidEvery report carries the ID you were given at send time.
2
Final states onlyYou hear about a message when it is delivered or has failed.
3
One callback URLThe same endpoint receives reports and replies.

Delivery logIllustrative

9f2a7c10+1 415 ••• 0123Deliveredjust now
9f2a7c11+91 98••• 43210Delivered3 s ago
9f2a7c12+44 7••• 123456Pending5 s ago
9f2a7c13+91 99••• 00012Failed9 s ago

Know before you send

See how a message is counted

Longer text and non-Latin characters change how many parts a message is billed as. Try your own wording, and look up a number before you send.

Message text

GSM746 characters160 per part

1partbilled separately

Part 1
46 / 160

One part holds 160 characters in GSM7 or 70 in Unicode. One non-GSM character, such as an emoji or a Hindi letter, switches the whole message to Unicode.

Why an API

Stop gluing messaging together by hand

Drag the divider to compare.

With the SMS API

Messages sent from your own code
A report for every message
Replies pushed to your system

Without a messaging API

Manual exports and uploads
No idea if a message arrived
Replies land in someone’s inbox

Before you go live

A short pre-launch checklist

0%0 of 9

Tick items off as you go. Nothing here is saved.

01AccountCreate an account and copy your access keyRegister your sender IDAdd your callback URL

02Compliance (India)Register your entity under DLTGet headers and templates approvedRespect promotional sending hours

03TestingSend to your own number firstLog every msgid you receiveCheck that a failed status is handled

Keep building

More for your integration

Pick up wherever you are. Each of these builds on the same account and access key.

Answers To Your Questions

SMS API — frequently asked questions

Pass your access key in a Token header on every request, along with Content-Type: application/json.

Every send returns a msgid. Point us at a callback URL and we post a status report to it when the message reaches its final state.

160 characters on GSM7 encoding, or 70 on Unicode. Longer messages are joined from several parts, each billed separately.

Yes. Inbound replies are delivered to the same callback URL and marked as mobile originated.

Yes. SMS to Indian numbers must use an approved entity, sender header and template. Our team helps you register them during onboarding.

Get Started

Send your first SMS in minutes

Create an account, grab your access key and make your first request.

Start free See pricing