November 4, 2026 路 4 min read
Why Google Voice and TextNow numbers get rejected
Many services refuse Google Voice and TextNow numbers at signup. Here is how they detect them, and what kind of number gets the code instead.
Google Voice, TextNow and similar apps give you a free number that runs over the internet. They are handy for calls and texts, but many services refuse them at signup with messages like "this number cannot be used" or simply never send the code.
How services tell
When you enter a number, a service can look up its line type in carrier databases. That lookup says whether the number belongs to a mobile network or to an internet calling (VoIP) provider. Free VoIP numbers are cheap to create in bulk, so services that fight spam or fake accounts often block the whole category.
Why recycling makes it worse
Free app numbers are reassigned when a user stops using them. The next person gets a number that may already be linked to accounts on WhatsApp, Telegram or Google, so the service rejects it as already used.
What works instead
A number from a real mobile operator, reserved for you and used once, behaves like a normal signup. Carrier and routing details differ by country, so no provider can promise every number is classified the same way. What you can check is delivery: TempCode shows the last hour鈥檚 success rate per country before you pay and refunds you if no code arrives. For Google itself right now:
FAQ
Is a TempCode number VoIP?
We rent real operator numbers used once. Classification varies by carrier and country, so we focus on what we can guarantee: the code arrives, or you are refunded.
Can I keep using Google Voice for calls?
Yes. The issue is only with services that refuse VoIP numbers for verification.