Because of a few personal needs, I often need an overseas phone number. So I have been looking for an overseas SIM that is affordable and reasonably stable.

Before this, I had been using Ultra Mobile’s U.S. PayGo plan at $3 per month, and a 3HK roaming card from Hong Kong that costs HKD 268 per year and includes 45 GB of data. Both have their drawbacks. The PayGo card can make and receive calls and texts in mainland China, but it cannot roam for data. The 3HK card can roam for data in mainland China, but its IP address is in Hong Kong, so it cannot log in to ChatGPT, and it cannot make calls or receive texts.

For a long time, I had been looking for an overseas SIM that could roam for data in mainland China, use a non-Hong Kong IP address, receive SMS messages, and still stay cheap. Then I found RedteaGo , a global mobile data product from the Austrian carrier RedteaMobile.

RedteaGo’s global plans have several advantages:

  1. During the validity period, up to 365 days and renewable, they can receive SMS messages for free, which is useful for registering apps. This applies to global plans only.
  2. They support data roaming in 130+ regions, including mainland China, and the IP address is in Europe, so logging in to ChatGPT is easy. This also applies to global plans only.
  3. The price is low. The 100 MB keep-alive plan costs only $3.20 per year. With referral credit, it can be as low as $2, or about 15 RMB, for one year.
  4. eSIM is supported, so no physical SIM card is needed.
  5. No real-name registration is required.

You can buy RedteaGo plans from the official website or the official app. If your phone supports eSIM, you can buy directly in the app. If your phone does not support eSIM and you need to use a third-party physical eSIM card, it is better to order from the website, because only website orders provide an eSIM QR code.

First, register a RedteaGo account with your email address. You can use my referral code MASO0042; both you and I will receive $3 in credit, which can be used toward future plans. With the referral credit, the cheapest keep-alive setup costs only $2 for a full year.

After registration, you can choose a plan. If you want to use the $3 referral credit when buying a plan, top up your account first and then buy the plan. If your balance is lower than the plan price at checkout, you can only pay the full plan price directly and cannot apply the referral credit. This is easy to miss.

The minimum top-up amount is $2. Payment methods include Apple Pay, international credit cards, and Alipay. The screenshot below shows the top-up flow in the RedteaGo app. Before topping up, check the price of the plan you want. Make sure your top-up plus the $3 credit is greater than the plan price, so the balance can be used at checkout.

Take the cheapest $3.20 plan as an example. After registering with the referral code, the account starts with a $3 gift balance. If we top up the minimum $2, the account balance becomes $5. When buying the plan with balance payment, $1.80 remains in the account and can be used for another plan later.

After topping up, you can buy a plan. I recommend these three:

  1. Global, 130+ regions, 100 MB for 365 days, free SMS reception, $3.20, European IP.
  2. Global, 130+ regions, 1 GB for 365 days, free SMS reception, $19.90, European IP.
  3. Mainland China, 50 GB for 365 days, no SMS support, $26.19, Hong Kong IP.

All three can roam for data in mainland China. The global plans use a European IP address; the mainland China plan uses a Hong Kong IP address. The global plans include a +43 phone number and can receive SMS messages for free. The mainland China plan does not include a phone number and cannot receive SMS.

Choose based on your needs. For the same 365-day Hong Kong IP roaming use case, the third plan costs only about 190 RMB, far lower than the HKD 268 3HK 45 GB plan, though it lacks the phone number and SMS function. If you count the $3 referral credit, 50 GB for 365 days can be had for about 170 RMB. Not bad at all.

Activation is simple. On an eSIM-capable iPhone, just tap the activation button and follow the steps.

After activation, the carrier shown in the upper-left corner is RedteaMobile, and the plan page shows remaining data and validity.

The validity period starts after successful activation. No matter which plan you buy, the plan expires if any of the following happens. After expiration, you must buy a new plan to continue using it, and the previous phone number cannot be recovered.

  1. No usage for 30 consecutive days after activation.
  2. The plan’s data is used up.
  3. The validity period ends.

If you want to keep your phone number before the plan expires, remember to renew before any of these conditions is triggered. Once the plan expires, the old number is gone.

Overall, RedteaGo is a low-cost overseas mobile product that can provide a native European IP address. It is suitable for users with specific needs, can replace 3HK in many scenarios, and does not require real-name registration. Finally, here is my referral code again: MASO0042. If you register with it, both of us receive $3 in credit that can be applied to plan purchases.