Codex asks you to verify a phone number? What to do when your number doesn't work
When Codex asks for phone verification, OpenAI only texts mobile numbers in the countries it supports; VoIP and most virtual numbers are refused. If you have no such number, the simplest fix is a US number on a physical SIM that receives this one code.
- OpenAI's Help Center says you may be asked to verify a phone number when using Codex in the desktop app, and email or an authenticator app can't replace that step.
- Numbers from unsupported countries, landlines, Google Voice and other VoIP numbers are not accepted.
- Without a supported mobile number, a US +1 SIM number can receive the code; use one number for one OpenAI account.
Why Codex asks for your phone number
OpenAI's Help Center says phone verification isn't generally required for ChatGPT, but you may be asked to verify a phone number when you access Codex in the ChatGPT desktop app, and email or an authenticator app does not replace that step. Generating your first API key on the developer platform also needs a phone check.
In practice it shows up when you first sign in to the Codex app or CLI with your ChatGPT account, when you sign in from a new computer or network, or on a fairly new account. Paying Plus and Pro users see it too: it is a security check, not a sign that something is wrong with the account. OpenAI hasn't published the full rules, so the same steps prompt some people and not others.
The verification page only texts mobile numbers in countries OpenAI supports. Until you pass it, Codex won't sign in, even if ChatGPT on the web works fine.
Which numbers work and which don't
| Number | Works? | Notes |
|---|---|---|
| Numbers from unsupported countries | No | For example mainland China, Hong Kong or Russia: the page can't text them. |
| Landlines and premium numbers | No | The Help Center says they're not supported. |
| Google Voice and other VoIP numbers | No | Not supported; usually refused as soon as you submit. |
| Free public SMS sites | Rarely | Shared by many people, often refused or already used up, and anyone can read the code. |
| A mobile SIM number in a supported country | Yes | For example a US +1 number on a physical SIM, as long as you can read its texts. |
OpenAI Help Center: Can I use a premium number, landline, Google Voice, or other VoIP phone number?
No supported number? Your options
From easiest to most effort:
- Your own mobile SIM or eSIM in a supported country: use it; the number stays yours, so later checks are easy.
- A friend's or relative's number: works once, but the number isn't yours, so the next check means asking again, and that number can't verify other accounts later.
- A paid verification number: a SIM number in a supported country bought for this code. Make sure it is a physical SIM rather than VoIP, and that you can swap it or get a refund if nothing arrives.
Verifying Codex with a US number, step by step
Pay2GPT's Codex login number is a US +1 number on a physical SIM, $3.49 per number, valid for 21 days:
- Pay by card, Alipay or USDT. No sign-up, just an email.
- A US +1 number is assigned on your order page within seconds and emailed to you.
- On the Codex verification page, choose United States (+1), enter the number and send the code.
- The text shows on your order page; copy the code into the verification page.
- Nothing arrives? Switch network or VPN node and resend. Still nothing: swap the number on your order page, up to 2 times per order at no charge. If none of your numbers receives a text, the order page offers a refund to your original payment method.
After you've verified
- One number is for one OpenAI account. Verifying several accounts with one number tends to get them flagged.
- The number is valid for 21 days. If Codex asks again in that time, open your order page to read the new code.
- After 21 days the number is no longer yours. If a later check asks for it, OpenAI says you can try another supported mobile number you control while signed in to the same account.
- Codex then runs on your ChatGPT plan's usage. If you used a relay or CC Switch before, switch Codex back to the official sign-in first.
OpenAI Help Center: What does phone verification look like?
Common questions
Does every Codex sign-in need phone verification?
No. OpenAI says you may be asked when using Codex in the desktop app; whether you are depends on your device, network and account, and the full rules aren't published.
Can an email code or authenticator app replace the phone check?
No. OpenAI's Help Center says this step needs a phone number.
My country isn't in the list. What now?
OpenAI only texts numbers in the countries it supports. Use a mobile number from a supported country, such as a US +1 SIM number.
Will Codex ask for my phone again?
It can, for example after a new device or network. With a Pay2GPT number, open your order page within the 21 days to read the new code.
Do Plus users get asked too?
Yes. It is OpenAI's security check and applies to paid accounts as well; it doesn't mean the account has a problem.
Codex login number · $3.49 per number · 21 days · refund if no code
