If you want to add phone number login, OTP verification, or SMS notifications to your WordPress site, you need an SMS gateway. In this guide we cover the best WordPress SMS gateways, how they work, and how to connect them to your WordPress site in minutes.
What is an SMS Gateway for WordPress?
An SMS gateway is a service that lets your WordPress site send text messages (SMS) to users. The most common use case is sending a One-Time Password (OTP) for login or registration — instead of a password, users verify their phone number with a 6-digit code.
This is called OTP login or passwordless login, and it significantly reduces cart abandonment, fake registrations, and login friction on WooCommerce and membership sites.
How to Add an SMS Gateway to WordPress
The easiest way is to install the OTP Login With Phone Number plugin (free). It supports 20+ SMS gateways and lets you connect your gateway in minutes — no coding required.
Once installed:
- Go to Login Settings → Gateway in your WordPress admin
- Select your SMS gateway from the list
- Enter your API credentials
- Save — done
Best WordPress SMS Gateways in 2025
1. Firebase (Google) — Best Free Option
Price: Free (10,000 OTP/month) Best for: International sites, getting started fast
Firebase Authentication is the easiest and most popular free SMS gateway for WordPress OTP login. Google provides up to 10,000 free OTP SMS per month — more than enough for most small and medium sites.
Pros:
- Completely free up to 10,000 SMS/month
- Works in 200+ countries
- Highly reliable — Google infrastructure
- Easy to set up with the OTP Login plugin
Cons:
- Requires a Google Firebase account
- Not ideal for very high volume sites
How to configure Firebase for WordPress OTP →
2. Twilio — Best for International SMS
Price: Pay per SMS (~$0.0079/SMS) Best for: International sites, high volume
Twilio is one of the most reliable SMS providers in the world. It delivers messages to 180+ countries with excellent delivery rates. The OTP Login plugin supports Twilio in the free version.
Pros:
- Extremely reliable delivery
- Works globally
- Developer-friendly API
- Good documentation
Cons:
- Paid per SMS — costs add up at scale
- Requires credit card to start
3. Kavenegar — Best for Iran
Price: Paid (Iranian pricing) Best for: Iranian WordPress sites
Kavenegar is the most reliable SMS gateway for Iran-based WordPress sites. It supports pattern-based OTP which is required by Iranian telecom regulations. Available free in the OTP Login plugin.
Pros:
- Best delivery rates in Iran
- Supports OTP patterns
- Persian panel
- Free in the OTP Login plugin
4. Netgsm — Best for Turkey
Price: Paid (Turkish pricing) Best for: Turkish WordPress sites
Netgsm is Turkey’s leading SMS provider. The OTP Login plugin supports Netgsm for free, making it easy to add OTP login to Turkish WooCommerce stores.
Pros:
- Best delivery rates in Turkey
- Turkish character support (TR encoding)
- Custom sender name support
- Free in the OTP Login plugin
5. MSG91 — Best for India
Price: Paid (Indian pricing) Best for: Indian WordPress sites, WooCommerce
MSG91 is widely used for OTP delivery in India. It supports flow templates and transactional SMS — ideal for WooCommerce and membership sites with Indian users.
Pros:
- Excellent delivery rates in India
- Supports OTP flow templates
- Good API documentation
Cons:
- Available in Pro version of OTP Login plugin
6. WhatsApp (UltraMessage) — Best for WhatsApp OTP
Price: Paid Best for: Sites where users prefer WhatsApp over SMS
WhatsApp OTP is increasingly popular — many users prefer receiving their code via WhatsApp rather than SMS, especially in regions where WhatsApp is dominant (Middle East, South Asia, Latin America).
Pros:
- Higher open rates than SMS
- Free for users to receive
- Works where SMS is expensive
Cons:
- Available in Pro version of OTP Login plugin
- Requires UltraMessage account
7. Custom API Gateway — Best for Any Provider
Price: Depends on your provider Best for: Any SMS provider not listed above
The OTP Login plugin includes a Custom API option that lets you connect any SMS gateway that has a REST API. Enter your gateway URL, request method (GET/POST), headers, and body in JSON format. Use ${code} as a placeholder for the OTP code.
This means you can use local SMS providers in any country — no additional development needed.
How to configure a custom SMS gateway →
SMS Gateway Comparison Table
| Gateway | Free/Paid | Region | Free in Plugin |
|---|---|---|---|
| Firebase | Free (10k/month) | International | ✅ Yes |
| Twilio | Pay per SMS | International | ✅ Yes |
| Kavenegar | Paid | Iran | ✅ Yes |
| DrPayamak | Paid | Iran | ✅ Yes |
| Netgsm | Paid | Turkey | ✅ Yes |
| Custom API | Depends | Any | ✅ Yes |
| MSG91 | Paid | India | Pro |
| Paid | International | Pro | |
| Telegram | Paid | International | Pro |
| Alibabacloud | Paid | Asia | Pro |
| MessageBird | Paid | International | Pro |
| Vonage | Paid | International | Pro |
| Taqnyat | Paid | GCC/Arabic | Pro |
| Textlocal | Paid | UK/India | Pro |
| 2Factor | Paid | India | Pro |
| SMS.ir | Paid | Iran | Pro |
| MelliPayamak | Paid | Iran | Pro |
| FarazSMS | Paid | Iran | Pro |
Which SMS Gateway Should You Choose?
- International site → Firebase (free, easiest)
- High volume international → Twilio
- Iran → Kavenegar or DrPayamak
- Turkey → Netgsm
- India → MSG91 (Pro) or 2Factor (Pro)
- Middle East / WhatsApp heavy → WhatsApp via UltraMessage (Pro)
- Your own local provider → Custom API (free)
How to Add OTP Login With SMS Gateway to WordPress
- Install the free OTP Login With Phone Number plugin
- Go to Login Settings → Gateway and select your SMS gateway
- Enter your API credentials
- Create a page with the shortcode
- Test by visiting the page in a private browser window
The plugin works with WooCommerce out of the box — no extra configuration needed. After installation, OTP login appears automatically on WooCommerce My Account, checkout, and registration pages.
Frequently Asked Questions
Can I use multiple SMS gateways at the same time? Yes. The OTP Login plugin lets you select multiple gateways. Users will see a selector to choose which method they prefer (e.g. SMS or WhatsApp).
Is Firebase really free? Yes. Google Firebase provides 10,000 free OTP verifications per month. For most small and medium WordPress sites this is more than enough.
Can I connect my own local SMS provider? Yes. Use the Custom API option — enter your gateway URL and configure the request in JSON. No coding required.
Does this work with WooCommerce? Yes. The plugin integrates with WooCommerce login, registration, and checkout pages automatically.
What is the best SMS gateway for WordPress OTP login? Firebase is the best starting point — it’s free, reliable, and works globally. For paid options, Twilio is the most reliable for international delivery.
Conclusion
Adding SMS OTP login to WordPress is easier than ever. The OTP Login With Phone Number plugin supports 20+ SMS gateways and works with WooCommerce, LearnPress, and all major WordPress themes.
Start with Firebase for free — you get 10,000 OTP SMS per month at no cost. When you need more gateways or Pro features, upgrade to the Pro version.
Leave a Reply