An app calls a number invalid or not supported for one of four reasons: it is typed in the wrong format, it comes from a country the app does not serve, it is a line type the app refuses (landline, VoIP, burner), or its range is blocked. Fix the format first. If the app still refuses a correctly typed number, retrying will not help: the number itself is refused.
Rule out the format first
A format mistake is the cheapest cause to fix, and the only one where retyping helps. Check these three things before anything else:
- No national 0 after the country code: +44 7700 900123, not +44 07700 900123.
- The country code only once: if the app has a country list, type only the national part.
- The right country in the list: a flag left on your home country turns a foreign number into a wrong one.
Country by country, with special cases such as Mexico and Argentina: how to enter a number with its country code. If the format is right and the app still refuses, read on: the cause is one of the three below.
Country not supported by the app
Some apps only take numbers from the markets they serve, and say "not supported" for everything else, however correct the format.
- Sahibinden accepts Turkish mobile numbers only, because it sends its codes through Turkish operators.
- Kleinanzeigen accepts numbers from the EU, the EEA and Switzerland; UK numbers currently cannot be used.
- Apps built for a single market may expect a number from that market and refuse the rest.
If you live elsewhere, a number from the app's own country is the fix. Choosing the country explains how to pick one that works.
Line type and blocked ranges
| What the app says or does | |
|---|---|
| Discord | Refuses VoIP, burner and landline numbers; the number must belong to a mobile device |
| Airbnb | Says most virtual numbers, such as VoIP services, may not receive its code |
| "This phone number cannot be used for verification"; Google limits how many accounts each number can create |
Blocked ranges are the invisible version of the same thing. When a block of numbers has been misused, a strict service refuses all of it, often with the same "invalid" message, so you cannot tell from the wording.
WhatsApp at a glance
- Virtual numbers
- Often refused: try another country
- Code sent by
- SMS · phone call
- Code length
- 6 digits
- Asks for the number again later
- Yes
- One number per account
- Yes
Google at a glance
- Virtual numbers
- Often refused: try another country
- Code sent by
- SMS · phone call
- Code length
- 6 digits
- Asks for the number again later
- Yes
- One number per account
- No
What to do, in order
- Retype in international format Plus sign, country code, then the number without its national 0. Check the country selected in the app's list.
- Check the area code Countries such as Brazil and the US need it as part of the number.
- Try once more, not five times Repeated attempts can put a number on hold. Discord, for example, asks you to wait 24 to 48 hours after a timeout.
- Change the number, not the spelling If a correctly typed number is still refused, the line type or range is the problem. Use a mobile number, or a number from another country.
Common questions
Why does WhatsApp say my phone number is invalid?
Most often a leading 0 after the country code, or the wrong country in the list. If the format is right, WhatsApp is refusing that type of number or that range, and only a different number helps.
The app accepted my number, but no code arrives. Is that the same problem?
No. An accepted number has passed the check described here; a missing code is a delivery problem. See verification code not received.
Why does Discord reject my phone number?
Discord refuses numbers that are badly formatted, not valid for the country's numbering plan, VoIP, burner or landline. It also refuses a number that is already on another Discord account.
Is "invalid number" the same as "number already in use"?
No. "Already in use" means the number is fine but another account holds it. See one number, several accounts.