If you’re visiting the United Kingdom with a GSM unlocked iPhone 5, your main options for Pay As You Go SIMs are limited to three of the five major networks. At the time of writing, only Three, T-Mobile and O2 offer nano-SIMs on Pay As You Go (pre-paid) deals. Three will sell you a nano-SIM on a one-month rolling contract, but that’s not much use for travelers, as it’s subject to all the usual credit requirements. Vodafone and Orange have yet to announce any PAYG nano-SIM options, nor has the community-oriented GiffGaff network.
T-Mobile UK’s PAYG nano-SIM works just the same as any of the carrier’s other PAYG SIMs. After topping up at least £10 of credit, you can choose between three price plans for your iPhone 5 --
All of T-Mobile UK’s PAYG plans come with unlimited mobile data for browsing and email for the following month, plus a 500MB data allowance for media streaming, which should be more than enough for most travelers. In particular, that 70 minutes of international calls may be ideal for visitors to the UK who want an convenient way to call home without breaking the bank.
Next up is Three, which in our opinion offers the most attractive PAYG plans for heavy data users. You can top up £15 and get unlimited data, 300 minutes and 3000 texts, or top up £10 for 500MB, 100 minutes and 3000 texts. There's no international allowance included, however.
Three's PAYG nano-SIMs aren't available online yet, but its brick-and-mortar stores are now stocking them.
O2's pre-paid nano-SIM option is well hidden, but it does indeed offer them. O2 has a wide range of PAYG plans, each with varying benefits --
It’s also worth mentioning that nano-SIM “cutters” are available online to enable brave users to trim down micro-SIMs to nano-SIM size. If the gold contacts are the right size, you should be able to use one of these hole punch-like devices to cut down the plastic around your micro-SIM so that it’s the correct size for iPhone 5. You can also attempt this manually using a good old-fashioned pair of scissors, if you’re feeling adventurous.
Cutting down SIM cards can be hit and miss, though, so proceed at your own risk if you decide to go ahead with this. However, if successful, you’d be able to slice down any micro-SIM and use a PAYG SIM from any provider in your iPhone 5.
We’ve reached out to the other major mobile networks to see if they plan on offering PAYG nano-SIMs anytime soon. We’ll update this article with any new information they provide.