VoIP vs non-VoIP numbers for verification
The single most useful thing to understand about verification numbers is the line-type check.
SMS Nitro team ·
What is the difference between VoIP and non-VoIP numbers?
A non-VoIP number is a mobile carrier line backed by a SIM; a VoIP number is routed over the internet by a provider. Apps query the carrier database before sending an OTP and refuse VoIP types when they want to make sign-ups expensive. In the catalog, non-VoIP pools are labeled physical SIM.
How the check works
Number portability databases and carrier lookup services return the current carrier and the line type for any number. The lookup costs the app a fraction of a cent and takes milliseconds, so most large services run it on every sign-up.
Who refuses VoIP
- Always: Google, WhatsApp, PayPal, Venmo, Cash App, most banks, Uber.
- Often: Tinder, Bumble, Amazon, Microsoft, Discord in the US.
- Rarely: Telegram, forums, newsletters, most games.
Why non-VoIP costs more
Each physical-SIM number is a real card in a real device somewhere, with a carrier plan behind it. Virtual ranges scale in software. The price gap reflects that.
VoIP or physical SIM, side by side
VoIP vs physical-SIM numbers
| Criterion | Physical-SIM number | VoIP number |
|---|---|---|
| Origin | Mobile carrier, real SIM | Internet provider |
| Passes Google, WhatsApp, PayPal | Yes | Usually refused |
| Receives short-code SMS | Yes | Often not |
| Price per code | Higher | Lower |
| Best for | Strict apps, accounts you keep | Messaging, social, forums |
SMS Nitro at a glance
| Billing | Pay only if the code arrives. If no SMS arrives before the number expires, the frozen amount returns to your balance automatically, in full. |
|---|---|
| Number reserved for | Up to 20 minutes per activation. Rentals from 24 hours to 30 days with unlimited incoming SMS. |
| Payment | Card via Stripe (Visa, Mastercard, Amex, Apple Pay, Google Pay) or crypto (USDC or SOL on Solana). Minimum top-up $5. Card top-ups carry a 10% processing fee; crypto has none. |
| Subscription | None. Pay per verification; your balance never expires. |
| Countries | 180+ countries, including the United States, the United Kingdom, Canada, India, Germany, Brazil, Indonesia and the Philippines. |
| Apps | 700+ apps and websites: WhatsApp, Telegram, Google, Instagram, TikTok, Discord, OpenAI, PayPal, Tinder, Amazon and more. |
| Developers | REST API plus an SMS-Activate-compatible endpoint. API key available after your first top-up. No API surcharge. |
| Support | Tickets from the dashboard and email, answered by people. |
| Price | From $0.02 per verification code, depending on the app and the country. |
Frequently asked questions
Can a VoIP number ever pass Google?
Occasionally, in some countries. Not reliably enough to pay for the attempt.
How do I know which pool a country uses?
The catalog labels each country; app pages say when physical SIM is required.
Is physical SIM always worth it?
No. For Telegram and most social apps the virtual pool works and costs less.
Can VoIP numbers receive short codes?
Often not. Physical-SIM numbers receive everything.