SMS Verification API for Developers

The SMSBulk SMS verification API gives your code a real phone number on demand and hands back the verification code as soon as it arrives. One JSON API, one prepaid balance, automatic refunds when no SMS shows up.

Receive an OTP in three API calls

This is the whole loop: reserve a number, poll until the SMS code arrives, confirm it was used. The examples below run against the production API exactly as written, just export your key first.

const BASE = 'https://smsbulk.net/api/v1';
const KEY = process.env.SMSBULK_API_KEY; // smsbulk_...

async function api(path, options = {}) {
  const res = await fetch(BASE + path, {
    ...options,
    headers: { 'X-API-Key': KEY, 'Content-Type': 'application/json' },
  });
  if (!res.ok) throw new Error(res.status + ' ' + (await res.text()));
  return res.json();
}

async function main() {
  // 1) Buy a number for Telegram in the United States
  const activation = await api('/activations', {
    method: 'POST',
    body: JSON.stringify({ serviceCode: 'tg', countryIso: 'US' }),
  });
  console.log('Number:', activation.phoneNumber);

  // 2) Poll until the verification code arrives
  let code = null;
  while (!code) {
    await new Promise((r) => setTimeout(r, 5000));
    const a = await api('/activations/' + activation.id);
    if (a.status === 'RECEIVED') code = a.smsCode;
    else if (['CANCELLED', 'EXPIRED', 'REFUNDED'].includes(a.status)) {
      throw new Error('Ended without SMS: ' + a.status);
    }
  }
  console.log('Verification code:', code);

  // 3) Confirm the code was used
  await api('/activations/' + activation.id + '/complete', { method: 'POST' });
}

main();

Create a key under Dashboard, then explore every endpoint and response schema in the API documentation. If a code never arrives, the activation expires and your balance is refunded automatically.

From signup to production in four steps

What you get with the OTP API

A phone verification API is only useful if it behaves the same on request one million as it did on request one. These are the guarantees the platform is built around.

Live starting prices for popular services

Prices are per successful verification and vary by country. These are live starting prices from the catalogue, refreshed hourly on this page:

Exact per-country prices come from GET /v1/services/{slug}/countries, the same data the dashboard shows.

One API for every verification flow

Whether you call it an OTP API, a phone verification API or a receive-SMS API, the job is identical: your system needs a temporary number that can catch a verification code and hand it back as machine-readable JSON. That is the entire contract of POST /v1/activations.

Teams use it to verify signup flows in CI, to onboard fleets of business accounts, to test region-locked registration forms and to keep personal numbers out of third-party databases. Bulk usage is a first-class citizen: create activations in parallel, list them with cursor pagination and reconcile costs per activation from the wallet transaction log.

If your use case is the number itself rather than a single code, the virtual number API page covers provisioning, lifecycle and release in depth.

Built for AI agents too

SMS verification API FAQ

Keep exploring

Need the number as a resource rather than a one-off code? Read the virtual number API guide. Prefer a number that stays yours for days? See number rentals.