API

What is the recommended workflow to automate number rental and release using SMSVerifier API?

July 30, 2026 · 5 min read · 16 views
The recommended workflow to automate number rental and release with SMSVerifier API involves registering, renting a number via the API, polling for the OTP SMS, then releasing the number promptly to optimize costs and throughput.

API Registration and Authentication

Before automating number rental and release, you need to create an account on SMSVerifier and obtain your unique API key. This key authenticates your requests and keeps your usage secure.

Important context.

Your API key is your authentication token; keep it confidential and never expose it in client-side code.

Once registered, all API calls require this key as a query parameter or header for authorization. Here is a simple example of checking your account balance to verify your API key:

bash
curl "https://smsverifier.com/stubs/handler_api.php?api_key=YOUR_API_KEY&action=getBalance"
python
import requests
r = requests.get("https://smsverifier.com/stubs/handler_api.php", params={"api_key":"YOUR_API_KEY","action":"getBalance"})
print(r.text)
javascript
const r = await fetch("https://smsverifier.com/stubs/handler_api.php?api_key=YOUR_API_KEY&action=getBalance");
console.log(await r.text());

Automated Number Rental Process

After authentication, the next step is to rent a virtual phone number. The rental API endpoint requires parameters for the service (e.g. WhatsApp, Google), country, and optionally other filters like operator or region.

The API responds with a rented number and a unique rental ID for tracking.

Buy number
Enter it on target site
Wait for SMS
Use OTP

Example API call to rent a number:

bash
curl "https://smsverifier.com/stubs/handler_api.php?api_key=YOUR_API_KEY&action=getNumber&service=whatsapp&country=us"
Pro tip.

Always store the returned rental ID and phone number together to manage polling and releasing properly.

Polling for OTP SMS

Once the number is entered on the target site/app, the next step is to wait for the OTP SMS. The SMSVerifier API provides endpoints to check the status and retrieve the SMS text.

Poll the API periodically (e.g., every 5-10 seconds) using the rental ID until the OTP arrives or a timeout occurs.

Common pitfall.

Avoid excessive polling frequency to prevent request bans or rate limiting.

Example polling request:

bash
curl "https://smsverifier.com/stubs/handler_api.php?api_key=YOUR_API_KEY&action=getStatus&id=RENTAL_ID"

The response will indicate if the SMS is received and provide the OTP code.

Releasing and Managing Numbers

After successfully obtaining the OTP, or if no SMS arrives within the set timeout (usually 20 minutes), release the number to free it up and avoid unwanted charges.

Use the release API endpoint with the rental ID to mark the number as released.

bash
curl "https://smsverifier.com/stubs/handler_api.php?api_key=YOUR_API_KEY&action=setStatus&status=cancel&id=RENTAL_ID"
Important context.

Prompt releasing guarantees refunds if no SMS was received during the rental period.

If managing multiple concurrent rentals, maintain a data structure mapping rental IDs to numbers and statuses, periodically polling and releasing as appropriate.

Best Practices and Common Pitfalls

Throttle API calls

Implement delays between polling requests to respect API rate limits and avoid bans.

🗂️

Track rental IDs

Keep detailed logs of rental IDs, numbers, timestamps, and statuses for troubleshooting and auditing.

Set timeouts

Automatically release numbers after a defined timeout if no SMS arrives to optimize credit usage.

🔄

Handle errors gracefully

Check API error codes and implement retries or notifications for failures or expired rentals.

Automate smartly: timely release is as important as timely rental.

Frequently asked questions

How do I start renting numbers via SMSVerifier API?
Begin by registering and obtaining your API key, then use the rental endpoint to request a number for your target service and country.
What is the typical sequence to automate OTP receiving and number release?
Rent a number, enter it on the target site, poll the API for the OTP SMS, then confirm usage or release the number once done.
Can I automate releasing numbers to avoid extra charges?
Yes, using the release endpoint promptly after you receive the OTP or if no SMS arrives helps prevent unnecessary fees.
How do I handle multiple concurrent rentals efficiently?
Maintain a list of active rentals with unique IDs from the API, poll each for SMS status, and release or reuse numbers as needed.
What are common errors to watch for during automation?
Watch for expired rentals, incorrect service IDs, or exceeding number limits; always check API responses and handle errors gracefully.
Is there a way to test the rental and OTP flow before going live?
Yes, SMSVerifier offers sandbox and test modes in the API playground to simulate rentals and SMS reception without using real credits.

Ready to automate your number rentals?

Register and get your API key now to start renting and releasing virtual numbers efficiently with SMSVerifier.

Read the API docs
Tags: api automation virtual-numbers otp smsverifier
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