ZendSMS integration guide

HTTPS JSON API

Build directly on the ZendSMS API.

Use authenticated REST endpoints for SMS and OTP, then connect message IDs and delivery information to your own system.

Discuss your setup API documentation

REST API & WebhooksBusiness event

ZendSMS202 QUEUED

YOURBRAND

Your service request ZS-2048 is now being processed.

✓ Delivered

Integration typeHTTPS JSON API

Security patternServer-side only

Response202 Accepted + message_id

Common workflows

What you can send from REST API & Webhooks.

The flexible integration path for products, mobile apps, CRM, ERP and internal systems.

Send SMS

Queue an approved business message with your own client reference.

Send and verify OTP

Build a server-side verification flow with dedicated OTP endpoints.

Delivery status

Use message identifiers to reconcile message state.

Balance and controls

Read supported account information from documented endpoints.

Verified API pattern

From one business event to one trackable SMS.

This request uses the fields in the current ZendSMS Send SMS reference. Keep the API key in a secret store, attach a unique client_ref and save the message_id from the accepted response.

01
Define the workflow
Choose the event, recipient and message that should be sent.
02
Connect securely
Keep the API key on the server and make the request over HTTPS.
03
Map the template
Map the approved sender ID, recipient, message and client reference.
04
Test and launch
Check the result, segment count and delivery state before production.

POST /api/v1/send-sms202

Authorization: Bearer sk_your_api_key

{
    "recipient": "8801700000000",
    "sender_id": "YOURBRAND",
    "message": "Your service request ZS-2048 is now being processed.",
    "client_ref": "api-request-2048"
}

success: truestatus: QUEUEDmessage_id: UUID

Read the complete Send SMS reference

Included in the workflow

Build a production-ready flow, not just a send button.

Event-driven SMS

Send only when a selected business event occurs.

Every core SMS type

Use OTP, Masking or Non-Masking SMS for the approved use case.

References you can track

Keep your own client reference and the returned message ID.

Bangla and Unicode

Send Bangla, English or Unicode content for the customer journey.

REST API & Webhooks FAQ

Answers to review before production.

A concise guide to security, SMS types, delivery reconciliation and testing.

Should the REST API & Webhooks integration call the API from a browser?

No. A secret API key must never be placed in browser code or public JavaScript. Send requests from a trusted server, backend function or protected connector.

Which SMS types can REST API & Webhooks send?

You can use OTP, Masking and Non-Masking SMS for an approved use case. Sender ID and template activation remain subject to KYC, documents and applicable operator or regulatory approval.

How do I reconcile delivery results?

Attach a unique client_ref to each request and store the message_id returned in the accepted response. Reconcile delivery status using the current API documentation.

What should be tested before launch?

Test event mapping, recipient format, Bangla/Unicode segments, duplicate prevention, error handling and delivery results. Complete consent and compliance review before production.

Ready to connect?

Talk to the ZendSMS team about your REST API & Webhooks workflow.

Talk on WhatsApp

Chat on WhatsApp