The classic question for those considering a SIM Only plan - answered.

There are loads of different smartphones, tablets and dongles on the market, each with different features and specs. They all require a SIM card (perhaps with a SIM Only plan), but while all SIM cards work in the same way and do the same job, they also come in different sizes.

So, let’s get the different sizes out the way.



Standard SIM

This is the “normal” sized SIM, the one you probably remember from your first ever mobile phone. These SIMs are only used in older phones and devices. That means devices like the iPhone 3GS and Samsung Galaxy S II



Micro SIM

As the name suggests, the micro SIM card is a smaller version of a standard SIM card. It’s about half the size of a standard SIM and, while it was first used with iPhone 4, most modern smartphones now predominantly use a micro SIM. 



Nano SIM

This is the smallest SIM of the three – it’s around 40% smaller than a micro SIM. Apple has made the nano SIM the standard SIM for every phone from the iPhone 5, including the iPhone 8, iPhone 8 Plus and iPhone X.

More and more manufacturers are jumping on the bandwagon, and we reckon it won’t be too long before this becomes the new standard SIM. It’s extremely fiddly to use, but also kinda impressive that they crammed so much data into such a tiny blip.



Why have SIMs changed in size?

It might seem like showing off, but it mainly boils down to advances in technology and improved usability. A smaller SIM means you can have a thinner, lighter phone, and you’d be surprised how the newly saved space can be utilised to cram in other impressive bits of hardware.

So, you want to know what size SIM you need. Well, did you get your phone from Three?

If you didn’t buy your phone, tablet or dongle from Three, you may not have the correct-sized SIM for your device, especially if you’re on a SIM Only deal. If you don’t, you’ll need to visit a Three store or give us a call to get a different-sized SIM or a free SIM adaptor. There’s plenty of reasons to go for a Pay As You Go SIM too.

You may want to check out this guide on how to use a SIM adapter.

Getting a SIM Only card from Three

You can use Three SIMs in any 3G or 4G phone, tablet or dongle so long as it’s unlocked. Devices from Three come unlocked as standard, but if your device is locked to a different network, we can help you unlock it.

We offer plenty of SIM Only plans including a one-month rolling contract and 12-month contracts for any sized SIM.

To talk about the right SIM for you, pop into your nearest Three Store or give us a call on 0333 300 3333 (standard rates apply).