If your OpenAI signup or API verification keeps failing with "this phone number cannot be used", you are almost certainly hitting a VoIP block. OpenAI filters Google Voice, Twilio-style numbers, and most disposable SMS sites. A real UK +44 mobile eSIM is carrier-grade stock, so the verification SMS lands like any normal SIM. You pay in crypto, get the QR on screen, and read the code on your device.
Why OpenAI rejects most virtual numbers
OpenAI relies on carrier lookups to score a number's risk. Numbers that resolve to VoIP providers, shared pools, or known SMS-rental ranges get blocked at account creation and again when you add phone verification to an API/organization. A genuine mobile line on a UK network passes that lookup because it is not a pooled VoIP range.
What you get with a UK eSIM
- A real +44 mobile number (not VoIP, not shared) for the verification SMS.
- Unlimited incoming verification codes - reuse it for re-verification or a second org.
- No KYC, no account, no ID upload. Pay with one of 12 cryptocurrencies.
- Works from anywhere - you do not need to be in the UK to receive the code.
Step by step
- Buy on checkout ($25 per eSIM). TRC20 USDT or TRX usually confirms fastest.
- Scan the QR shown after payment and install the eSIM on your phone.
- At OpenAI signup or API phone verification, enter the +44 number.
- Read the incoming SMS code on the device and finish verification.
Honest limits
No provider can promise that any one platform will accept any one number forever - anti-fraud rules change. What a real carrier eSIM gives you is the best realistic chance versus VoIP, because the number is not in a flagged virtual range. If a specific code is delayed, wait a few minutes and request a resend before retrying.
Common questions
Does OpenAI accept UK eSIM numbers?
A real +44 mobile eSIM is a normal carrier number, so it passes the VoIP filter that blocks Google Voice and SMS-rental sites. Acceptance is not guaranteed by any provider, but a genuine mobile line is the most reliable option for OpenAI phone verification.
Can I use the same number for the ChatGPT app and the API dashboard?
Yes. Incoming verification SMS is unlimited, so the same +44 line can verify the consumer app and a separate API/organization phone check.
Do I need to be in the UK?
No. Incoming SMS works worldwide via roaming, so you receive the OpenAI code wherever you are.
Is it anonymous?
There is no KYC and no account. You pay in crypto and we never collect your identity. See no-KYC eSIM.
Related guides
Buy UK eSIM · Receive UK verification SMS · TRC20 crypto payment guide