Phone verification for ChatGPT, Codex and the OpenAI API
Creating an OpenAI account or using ChatGPT generally needs no phone number. OpenAI asks for one when you generate your first API key on platform.openai.com, and may ask when you open Codex in the ChatGPT desktop app. A US number gets the code by text only, never by email or a call. OpenAI says landlines, VoIP, Google Voice and premium numbers aren’t supported. For a one-off check, a week is enough.
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When OpenAI asks for a phone
| OpenAI | |
|---|---|
| ChatGPT | Not generally |
| The API | For your first key only |
| Codex | May ask, in the ChatGPT desktop app |
| How the code arrives | Text, for a US number |
| Email or call instead | Neither is offered |
| Its word on VoIP | Not supported |
From OpenAI’s help article on phone verification, read on 13 November 2026.
What OpenAI accepts
OpenAI’s help article is specific: “Landlines, VoIP numbers, Google Voice numbers, and premium numbers aren’t supported”. It gives the reason as those kinds of number being often linked to fraud or abuse.
Codes go by SMS or, where available, WhatsApp. WhatsApp is offered only in twelve listed countries, and the United States is not one of them, so a US number always gets a text. OpenAI can’t send the code by email or read it out on a call.
A number from us is a non-VoIP US number, outside the types OpenAI lists. OpenAI still decides whether to send the code; if it doesn’t arrive, cancel within 24 hours.
Receiving OpenAI’s code on a number from us
Get a number
A week suits a one-off API or Codex check. Keep the number’s page open.
Enter it at the API key or Codex prompt
On platform.openai.com, start creating your first API key, or open Codex in the ChatGPT desktop app. If OpenAI wants a number, it asks there. Choose the United States and type the ten digits. The code comes by text.
Copy the code back
The text lands on the number’s page with the code picked out. Copy it into OpenAI’s box.
How long to keep the number
A week ($7.99). OpenAI asks for phone verification on your first API key and not on later ones, and Codex may ask when you open it in the desktop app. A day ($3.99) is enough if you are verifying for one of them right now; a week leaves room if Codex asks a few days after you set up the API, or if you have to come back to it.
OpenAI’s help article doesn’t describe texting the number again after verification.
If OpenAI’s code doesn’t arrive
OpenAI offers no fallback by email or call, so a code that doesn’t come by text doesn’t come at all. If the screen asks you to use a different number, OpenAI’s advice is to try another supported mobile number you control.
If no text reached the number from us, cancel it from its page within 24 hours of buying. Other causes and checks are in verification code not received.
Once your own account is set up, ChatGPT can connect to a number from us over MCP to read codes from other sites you use. That is a different job, explained in how an AI agent receives a verification code.
Questions people ask
- Does ChatGPT need a phone number to sign up?
- Not generally. OpenAI says phone verification isn’t generally required to create an account or use ChatGPT; it comes up for your first API key and sometimes for Codex.
- Why does Codex ask me to verify a phone number?
- OpenAI says you may be asked to verify a phone number when you access Codex in the ChatGPT desktop app. The code comes by text, or by WhatsApp in the listed countries, and an email can’t stand in for it.
- Do I have to verify my phone for every OpenAI API key?
- No. Phone verification is required on platform.openai.com to generate your first API key, not later ones.
- Can OpenAI send the verification code by WhatsApp to a US number?
- No. WhatsApp is offered only in twelve listed countries, and the United States isn’t one of them, so a US number gets the code by text.
- Can I use a Google Voice number for OpenAI?
- No. OpenAI lists Google Voice numbers as unsupported, along with landlines, other VoIP numbers and premium numbers.
Sources
Read on November 13, 2026. Prices and policies change; if something here is out of date, write to [email protected] and we’ll correct it.