What SIM Card Do I Need For My Phone?

Mobile phones come in all shapes and sizes and surprisingly so do the SIM cards that go inside them. With three different sizes of SIM cards in use in the UK, this probably has you asking what SIM card do I need for my phone?

Last updated: 21st Mar 2019 at 12:29pm

What Are SIM Cards?

A SIM (Subscriber Identity Module) card is a small circuit board that holds critical information such as your mobile phone number and your service provider/network. A few decades ago, SIM cards were the same size as a credit card. These days, SIM’s can be as small as your fingertip.

No matter what phone you have, if it doesn't have a SIM card, then you will need one in order for the phone to work. Likewise, if you have SIM card and it does not fit into the phone, then you will need a replacement sim.

What Are The Different SIM’s?

The three sizes that are still in use are identified as Standard, Micro and Nano.


Standard SIM Card – The standard SIM (sometimes called Regular SIM) isn’t often used but you might need one if you have an older phone or a basic phone (sometimes called a feature phone). A Standard SIM has dimensions of 25×15mm and there is a reasonable amount of plastic surrounding the gold-coloured circuit board.

Micro SIM Card – Introduced in June 2010, the Apple iPhone 4 was the first phone to use a Micro SIM. The card has the same size circuit board as a Standard SIM but the excess plastic surrounding this has been removed. A Micro SIM is sometimes supplied in what is known as a Combi SIM. A Combi SIM is a Standard SIM but the central part surrounding the circuit board is perforated. This allows you to push the central segment out, giving you a Micro SIM that has dimensions of 15×12mm.

Nano SIM Card – Released during October 2012, the Nano SIM was first used by the Apple iPhone 5. Most new smartphones use a Nano SIM, which has dimensions of 12.3×8.8mm.

Purely for your interest, we will also mention that there is a new type of SIM card being used in some products. For now, this does not include mobile phones but it may in the future:

e-SIM/eSIM – This is an embedded SIM, meaning that it is actually built into the device and cannot be removed. The Apple Watch Series 3 has an e-SIM so that it can be used as a stand-alone device. e-SIMs are also used in new EU 2018 models of car. The European Commission has insisted that they have an eSIM built in, so that anyone can contact the emergency services, in the case of an accident.

Which SIM Card Do I Need?

A common question that is asked is: What SIM do I need in my phone? Below, we highlight which SIM card works in each most of the popular handsets. 

Select your manufacturer:

Apple iPhone Model SIM Card Size
Apple iPhone 3GS Standard SIM
Apple iPhone 4 & 4s Micro SIM
Apple iPhone 5, 5c, 5s Nano SIM
Apple iPhone 6, 6s & Plus Nano SIM
Apple iPhone 7, 8 & Plus Nano SIM
Apple iPhone SE Nano SIM
Apple iPhone X, XR, XS & Plus Nano SIM

Samsung Device Model SIM Card Size
Samsung Galaxy S10+ Nano SIM
Samsung Galaxy S10 Nano SIM
Samsung Galaxy S9+ Nano SIM
Samsung Galaxy S9 Nano SIM
Samsung Galaxy S8+ Nano SIM
Samsung Galaxy S8 Nano SIM
Samsung Galaxy S7 edge Nano SIM
Samsung Galaxy S7 Nano SIM
Samsung Galaxy S6 (all models) Nano SIM
Samsung Galaxy S5 (all models) Micro SIM
Samsung Galaxy S4 (all models) Micro SIM
Samsung Galaxy Note 9 Nano SIM
Samsung Galaxy Note Edge Micro SIM
Samsung Galaxy Note 8 Nano SIM
Samsung Galaxy Note 7 Nano SIM
Samsung Galaxy Note 6 Nano SIM
Samsung Galaxy Note 5 Nano SIM
Samsung Galaxy J7 (2018) Nano SIM
Samsung Galaxy J7 (2016) Micro SIM
Samsung Galaxy J7  Micro SIM
Samsung Galaxy J3 (2018) Nano SIM
Samsung Galaxy Ace 3 & 4 Micro SIM
Samsung Galaxy A9 (2016) Nano SIM
Samsung Galaxy A8 (2016) Nano SIM
Samsung Galaxy A7 Nano SIM
Samsung Galaxy A5 (all models) Nano SIM
Samsung Galaxy A3 (all models) Nano SIM

Huawei Handset Model SIM Card Size
Huawei Mate X Nano SIM
Huawei P Smart 2019 Nano SIM
Huawei Mate 20 Lite Nano SIM
Huawei Mate 20 X Nano SIM
Huawei Mate 20 Pro Nano SIM
Huawei Mate 20  Nano SIM
Huawei P9 Plus Nano SIM
Huawei P9 Lite Nano SIM
Huawei P9  Nano SIM
Huawei P8 & P8 Max Nano SIM
Huawei P20 Pro Nano SIM
Huawei P20 Lite Nano SIM
Huawei P20  Nano SIM
Huawei P10 Pro Nano SIM
Huawei P10 Lite Nano SIM
Huawei P10 Nano SIM
Huawei Mate 9 & 9 Pro Nano SIM
Huawei Y6 (2017) Mico SIM

If you have another phone then you can take a look at the instruction manual for your phone to identify which SIM card is needed.

If you order a new SIM card from Asda Mobile then we will send you all three sizes of SIM, to ensure you get the card that you need. This article includes a wider range of sim card sizes.

Where is the SIM Card Slot Located?

When your new SIM card arrives, you will need to put it in the phone. The SIM card slot is usually in one of three places:

  1. Under The Back Cover – If the back cover is removable then the SIM card slot may be visible straight away.
  2. Under The Battery – If the battery is removable then the SIM slot may be under this.
  3. Exterior SIM Card Slot – If you notice a little cover on the side of the phone with a small hole in it, then this may be the SIM card holder.  You can use the SIM ejector tool that is supplied with the phone or a pin to eject the holder. Sometimes these are multi-function holders that also have a slot for you to insert a microSD memory card.

The SIM card is usually inserted with the circuit board facing down. All SIM cards have a 45-degree notch in one corner and this means that the card can only be inserted one way.

Asda Mobile SIM Only Deals

We have some really great news for you next, you can order your Free SIM Today from Asda Mobile. There are no sizing issues with Asda Mobile as we send out a card that includes all three sizes.

If you have a mobile phone number with another network, then you can bring this with you when you join Asda Mobile. Find out how to keep your old number.

We have lots of super sim only deals to suit everyone's needs. No contract or credit check just great value and service. Check out our sim only deals.

We aim to deliver your SIM card the next day if you place your order before noon on Mon-Thurs.

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