SIM card sizes: standard, micro and nano explained

If you have a phone, you’ll need a SIM card to go with it. Physical SIM cards come in three sizes: Standard, Micro and Nano. You can also get digital eSIMs, which take up no space at all. Read on to find out more.

When talking about the three types of physical SIM cards, there’s only one thing that’s different between them: the size.

And when it comes to size, it only means one thing: the amount of plastic around the chip. In fact, the chip is the same size in all three SIMs.

What is a Standard SIM card?

The first SIM card on the scene, the Standard SIM dates all the way back to 1996.

As well as being the oldest of the bunch, it’s also the largest, coming in at 15 x 25mm.

Despite its name, Standard SIMs are quite rare these days – most smartphones no longer use this size of SIM.

What is a Micro SIM card?

Measuring 12 x 15mm, the Micro SIM is smaller than the Standard SIM.

It made its debut in 2003, so it’s also fairly old. Like the Standard SIM, it’s not widely used anymore.

To illustrate, the iPhone 4 uses a Micro SIM, but the iPhone 5 uses a Nano SIM.

What is a Nano SIM card?

Introduced in 2012, the Nano SIM is the most recent and smallest version of SIM card.

It measures a mere 8.8 x 12.3mm, and there’s almost no blank plastic around the chip.

These days, it’s by far the most common and widely used SIM size. If you have a modern handset, it most likely uses a Nano SIM.

To give some examples, Apple has been using Nano SIM cards since the iPhone 5 in 2012, while Samsung’s had it since the Galaxy S6.

What size SIM do I need?

If you’re getting a physical SIM card for your phone, you’ll probably need a Nano SIM.

If you’re not sure which SIM you need, don’t worry. Most networks send out a Multi SIM (also called a Combi SIM or Trio SIM), which is a SIM card that contains all three sizes. Once you’ve figured out the size you need, you can use the perforated lines on the card to pop out the correct size.

This means you can order a SIM card in advance, without needing to specify the size you want.

What is an eSIM?

An eSIM is a digital SIM card that’s built into your phone; the “e” stands for embedded. Choosing an eSIM means you won’t have to put a physical card in your phone, which frees up space inside your phone for things like a bigger battery.

What’s more, it lets you switch networks without changing your SIM card. As long as your device is network unlocked, you can simply activate your new eSIM using your phone.

Most network providers, including major brands such as Vodafone and EE as well as smaller players such as Smarty and Lebara, offer digital eSIM plans. You can also buy travel eSIMs that allow you to avoid roaming charges by using international data plans while overseas.

Both types of eSIMs can be used with most smartphones released after 2018. Devices compatible with eSIMs include:

• Apple iPhone (11 onwards)

• Samsung Galaxy (S20 series onwards)

• Google Pixel (4 onwards)

Most eSIM-compatible devices can also be used with Nano SIMs. However, there are some exceptions, such as iPhones (14 onwards) purchased in the USA, which only support eSIMs. Apple iPhones bought in the UK and Europe still have physical SIM slots.

SIM card dimensions

• Standard SIM: 15 x 25mm

• Micro SIM: 12 x 15mm

• Nano SIM: 8.8 x 12.3mm

Recommended SIM-only deals

If you’re happy with your current phone, or plan to buy a new one, you’ll need a SIM-only deal.

It’s the cheapest and most flexible option. Rather than being tied to a 12-month or 24-month contract to pay off a handset, you can get one-month rolling contracts for a SIM card with a monthly allowance of data, minutes and texts.

Budget networks like Asda Mobile, giffgaff, iD Mobile and VOXI all offer affordable SIM-only deals.

You can also compare SIM-only deals with other networks such as Lebara, Three, Vodafone, iD Mobile, and O2 with MoneySuperMarket.

When choosing a deal, think about how much mobile data you’ll need per month, as well as how many minutes and texts you want (many deals offer unlimited calls and texts).