---
title: "Send OTP API Reference"
description: "Send a one-time password (OTP) to a customer's primary mobile number to start mobile verification."
canonical: "https://eps.eko.in/docs/mobile-otp-send"
---


> **Canonical URL:** https://eps.eko.in/docs/mobile-otp-send
> This is a machine-readable Markdown version of the page for AI agents and LLMs. The primary (HTML) version lives at the canonical URL above.

# Send OTP API Reference

`POST https://staging.eko.in/ekoapi/v3/tools/kyc/mobile/otp`

Send a one-time password (OTP) to a customer's primary mobile number to start mobile verification.

Triggers an OTP SMS to the supplied mobile number and returns a transaction id plus the OTP expiry timestamp. The customer enters the OTP, which you confirm with the Verify OTP API. By default the SMS is sent with the **Eko India** sender signature; to use your own Sender ID and template, complete telecom DLT registration (see below).

> View product & pricing details: [Mobile/OTP Verification](https://eps.eko.in/products/mobile-otp-verification-api.md)

## Body parameters

| Field | Type | Required | Description |
| --- | --- | --- | --- |
| initiator_id | string | yes | Registered mobile number of the API user (see Platform Credentials). e.g. 9962981729 |
| client_ref_id | string | no | Unique reference id per API call, generated by your system. e.g. REQ-20260101-001 |
| csp_id | string | yes | Customer Service Point id of the agent/retailer the OTP is being sent on behalf of. e.g. 9002336768 |
| mobile | string | yes | Customer's 10-digit primary mobile number to send the OTP to. e.g. 9002336768 |

## Headers

| Field | Type | Required | Description |
| --- | --- | --- | --- |
| developer_key | string | yes | Static API key issued to your account after KYC. |
| secret-key | string | yes | Dynamic per-request signature: base64(HMAC-SHA256(timestamp, base64(access_key))). |
| secret-key-timestamp | string | yes | Current time in milliseconds since UNIX epoch, used to compute secret-key. Must match server time. |
| content-type | string | yes | application/json e.g. application/json |

## Response

⭐ marks fields highlighted as verifiable.

| Field | Type | Description |
| --- | --- | --- |
| status | number | Primary success indicator (0 = success). |
| message | string | Human-readable response / error message. |
| response_status_id | number | Granular status id; see the shared error-codes table. |
| response_type_id | number | A unique id for every possible response shape (success or error) — useful for client logic branching and analytics. |
| data | object | API-specific response payload. |
| data.client_ref_id | string | Unique reference id for this OTP request, echoed back. |
| data.initiator_id | string | Registered mobile number of the API user that initiated the call. |
| data.otp_expiry_timestamp ⭐ | string | Timestamp until which the OTP stays valid. Verify before this time. |
| data.tid | string | Unique transaction id for this OTP send, for tracking and support. |

## Example request

```json
{
  "initiator_id": "9962981729",
  "client_ref_id": "REQ-20260101-001",
  "csp_id": "9002336768",
  "mobile": "9002336768"
}
```

## Example response

```json
{
  "status": 0,
  "response_status_id": 0,
  "response_type_id": 1623,
  "message": "OTP has been sent",
  "data": {
    "client_ref_id": "211101129871",
    "initiator_id": "1234567891",
    "otp_expiry_timestamp": "Fri May 22 16:04:04 IST 2026",
    "tid": "2886978474"
  }
}
```