What’s the use of having a UK SIM card? Besides basic number retention and registering for overseas software, the main benefit is taking advantage of UK promotions. Most money-transfer apps offer relatively generous UK bonuses (because the same amount is “worth more”). At the same time, with a UK number, you can activate a UK physical bank account through SIM verification. Compared with other regions, UK banks let you build credit with Monze, after which you can open accounts with other physical banks as well (though most require SIM verification; those that don’t generally require credit history).
Here’s a brief overview of the activation and number-retention costs for each SIM.
(Disclaimer: I’m only sharing what I know, and some information may be inaccurate. Please make your own judgment.)
giffgaff
There was a wave of account bans before, but they later apologized to some users. Personally, I think those who received compensation should be able to continue using the service. After all, giffgaff is one of the few SIM cards that can be activated and used directly in mainland China.
Minimum top-up: £10 per transaction
Number-retention policy:
Activity required every 6 months
20 pence/MB while roaming
30 pence/text message
voxi
One of the mainstream options for keeping a number active.
Those with a student email address can apply for a discount code
or buy a pre-activated SIM/discount code.
Some people also say that a student email address isn’t necessary:
You then have to wait for it to send an email. If you receive one, don’t open it right away—wait a little longer, as the discount code is only sent at the very end.
(I wasn’t successful, though, and bought a pre-activated number directly.)
Without a discount code, it costs £10 per SIM.
Activation seems to still require Wi-Fi Calling, but I’ve heard it’s easy to get working.
Uses the Vodafone network. Minimum top-up: £5 per transaction.
Number retention:
One activity every six months
£0.24 per roaming text message
£0.20 per Wi-Fi Calling text message
ctexcel
It has no fair-use policy—in other words, as long as you pay the maintenance fee, your number won’t be suspended.
Minimum top-up: £5 per transaction
Number retention:
Option 1: Buy a data plan
Consider this if you also need UK data.
Option 2: Send one text message every 90 days to keep the number active, at a cost of £0.10
Additionally:
You must have some usage activity within 10 days of activation, or the number will stop being maintained and can no longer be used. For a regular SIM, the stated requirement is usage activity after activation in the UK or Europe; for a Cool Play SIM, it says activation in the UK or overseas, but usage in the UK within 10 days; for an eSIM, the instructions say it must be used in the UK or EU within 10 days.
This SIM must also be activated within the UK, meaning you need to initiate Wi-Fi Calling and then dial 888 to activate it.
Also, I’ve heard that it receives quite a lot of spam calls and messages.
cmlink
This SIM also requires Wi-Fi Calling, and I’ve heard activation isn’t easy.
It’s best to physically leave mainland China and activate it in “the UK, Hong Kong, the EU, or designated regions”—Hong Kong is obviously the most convenient option.
However, it has a fair-use policy.
—If you use it in mainland China for an extended period, you may encounter permanent roaming restrictions: if, during any consecutive 120-day period, you spend more time outside the UK than in the UK, or your overseas calls, texts, and data usage exceed your UK usage (counted from the activation date, or based on the actual number of days if fewer than 120), you’ll first receive a warning text. If nothing changes after another 15 days of roaming, roaming will be suspended. Roaming can only be restored if your explanation is accepted; otherwise, you’ll have to wait until you return to the UK.
Minimum top-up: £6 per transaction
For number retention, the homepage promotes a £15 one-year option that keeps the number active for 365 days, and says the UK number can be retained in China. (Customer service says you need to contact them by phone to activate it; make your own judgment.)
The number-retention cost is relatively high, so it isn’t recommended.
lyca
Activation still requires Wi-Fi Calling.
(If you can’t activate this one, you can apply for a refund—I’ve tried that with other cards, so I can’t say, but I have received a refund for this one, so I’m mentioning it.)
Insert the physical SIM and wait for it to recognize the Lyca network and receive a confirmation text containing the number, then restart the phone; an eSIM activates immediately after scanning the QR code. If you don’t activate it within 30 days of placing the order, the selected plan or promotion will expire.
Official purchase link
(It’s kind of hard to believe—the activation fee used to be £2.50, but it’s now £3.)
Minimum top-up: £5 per transaction
For number retention, if there are no calls, texts, data usage, or top-ups for 90 days, you’ll receive a text or email reminder, followed by an additional 30 days.
Roaming in mainland China: £0.48 per text message
Asda
A mobile virtual network operator operated by the UK supermarket chain Asda, using the Vodafone UK network.
Official purchase link
Payment for this SIM may be somewhat troublesome—you need a UK card, and I don’t know whether Krak will work.
It also has a 63-day roaming restriction outside the UK.
SIM activation: £4
Text-message number retention: £0.20 per message
Minimum top-up: £2 per transaction
lebara
Another mainstream option for keeping a number active (mainly because of the cashback).
(Copied from elsewhere.)
Spend £2.96 through TopCashback UK to buy two Lebara eSIMs and get £39.60 in cashback:
£10 for registering as a new user on the platform, £17 from Confused, and £12.60 from Uswitch, for a total of £39.60.
A UK IP address is required.
Can be activated in China (Apparently, the issue is that you may not receive the verification code despite having a signal. It’s said that you then need to top up £5 in pay-as-you-go credit and contact customer service to remove the roaming restriction. Please verify this yourself—the reviews seem quite bad.)
Tutorial:
-
Using a UK IP address, register on TopCashback
-
Choose Connect to Confused, then Get 17 Cashback.
-
Once inside, find Compare SIM only deals and click it.
-
In the left-hand menu, under Network, select Lebara. Find the plan with 5 GB of data per month, priced at £1.48, and click Buy now.
-
You’ll be redirected to the Lebara website. Select iPhone 17 Air as the phone (this option is required to purchase an eSIM), enter the email address where you want to receive the eSIM, set a login password, and place and pay for the order.
-
After completing the steps above, you’ll receive the £10 registration reward and the £17 order reward. The £17 order reward appears the next day. The second order works similarly:
Link
If you recently received a 17-day or 24-hour activation countdown, quickly insert the SIM and dial 5588 again to activate it. If the deadline passes, the order will be automatically refunded, and you may not receive the cashback after a refund.
Number retention: one activity every 90 days
Minimum top-up: £5 per transaction
Roaming texts: £0.48 per message
Local texts: £0.19 per message
vodaphone uk
The new Pay as you go service doesn’t support keeping a number active through account activity; you need to purchase a plan. The cost is too high, so I won’t go into detail.
These are the relatively common UK SIM cards I know about. However, most of them have restrictions on overseas roaming, so if you can get Wi-Fi Calling working, it’s best to use Wi-Fi Calling.
Some plans renew automatically, so remember to cancel them.
One more reminder: UK credit is interconnected. If you close an account in one place, you’ll most likely be screwed across the UK, so don’t open bank accounts recklessly.
(Also, I previously wrote a post with affiliate links and hardly anyone responded. Why are the comments under other people’s posts so active? Hyw, “I was here first.”)