Chat with us:
0800 999 2 999

Business Mobiles company logo in heart

What Is A SIM Card & How Does It Work?

What Is A SIM Card & How Does It Work?

How does a SIM card work and what is it

You may have a SIM card but have no clue as to what it actually does. We know that our mobiles need this tiny little card to allow us to make calls and send texts, however, have you ever really questioned what one is, or wondered how does a SIM card work? We are here to break it down for you. Read on to learn more!

What Is A SIM Card?

The concept of a SIM card may seem quite complicated and difficult to wrap your head around, however, it is integral for your mobile.

The acronym SIM stands for Subscriber Identity Module. It stores important data, such as your unique phone number.

The card itself is a small piece of removable plastic that can be inserted into your mobile. Your phone provider (or Businessmobiles.com) will provide you with a SIM card that can be used in any mobile device providing it is the correct size. Through your SIM card, you can access the same network, number, and messages.

FUN FACT: The first SIM card was invented in 1991 and was the size of a credit card!

What is a SIM card?

What Does It Do?

This little piece of plastic allows you to connect to your network provider. You can make calls and send messages, and even connect to mobile internet services. Without one of these cards, a phone can not make calls or access any of your data. When you place your card into any new phone it will retain all your contacts, phone number, and messages. So you don’t have to worry about losing touch!

In short, these cards are what differentiates your mobile from an MP3 player. Without it, a mobile isn’t really a mobile.

Not sure if you have one? Well, if you are able to make phone calls, send messages, and access mobile internet, then you have a SIM card!

The Different Sizes

If you have ever seen a SIM card then you know they are very small and very easy to misplace. Over the years these cards have changed a lot in size. As our mobiles got bigger the card got smaller to make room for all the exciting upgrades. Those extra cameras had to go somewhere!

SIM cards come in 3 sizes: a Standard, a Micro-SIM, and a Nano-SIM.

The size of the card you need depends on the mobile phone you choose. When ordering a new mobile package you will be provided with the suitable SIM size, so you do not need to panic. However if you are buying a SIM only plan then you need to ensure that you are ordering the correct size for your desired mobile. A quick Google search will reveal what size you will need.

Even though these cards can vary in size, they all contain the same amount of information and do the same job!

Different types of SIM card

How To Insert & Remove

Now you know what is a SIM card you may be wondering how do you get the card into your mobile? The instructions on how to insert one should be found in your new mobiles’ manual, but it is normally quite easy to locate.

For iPhone users you will see a tray on the right hand side of your phone that needs to be opened with the silver ejector tool (also found in the box). Or if you can not locate this a simple paperclip will suffice. Push it in gently and the tray will pop out for you to insert or remove your sim card.

For Samsung users you wil need to perform the same steps as above. If you are having trouble locating the tray make sure that if you have a removable back cover that this is removed. However, if you are still struggling to locate the SIM tray then you can always rely on Google to provide you with the answers.

And now you can insert and remove your cards with ease!

Check Out Our Sim Only Business Deals

If you are trying to save money for your business but need to get your hands on some brand new business mobiles, then look no further! We have a range of offers to suit any budget. From luxury handsets to affordable SIM cards, all at a cheaper rate than going directly to the network.

LIMITED JAN. SALE - Save up to 57% on your business mobile contract!

BusinessMobiles has been offering business mobile phone contracts for 23 years to more than 20,000 UK customers and works closely with all major UK networks.

Choose from a range of EE, Three, Vodafone and O2 discounted business mobile deals on Apple, Android, iPads, Broadband & Business SIM Only offers – Whether you are a sole trader or a corporate, we’ve got what you need for your business.

Browse the UK’s best business mobile deals now starting from £4.17 per month. Alternatively, call us on 0808 280 3 761 or send us a message to get your free quote. 

Our team of experts is ready to help you find multiple contracts or that one perfect package.




Business mobile deals in UK blog and news

Enjoying this article? Subscribe to our newsletter to receive weekly content just like this directly in your inbox!

By clicking on “Subscribe”, you agree to receive email communications from BusinessMobiles.com and understand that you can unsubscribe at anytime.


Related posts

gift list 2022
Mobile phone tips

Christmas Gift Guide 2022: Mobiles, Gadgets & Tech

Welcome to our Christmas Gift Guide of 2022 – we’ve compiled 14 of the best mobile phone & gadget gifts for this holiday season. Read through all of the greatest tech gifts of the year, perfect for friends, family & employees alike. Uncover the best mobile for gamers, great value super savers, the nearly indestructible Cat S42H+ & many more.

Read More »
Benefits of VoIP for small and large business
Mobile phone tips

5+ Benefits of VoIP for Business

As technology advances, so do the ever-increasing benefits of a VoIP system for business. These systems have hundreds of features and functionalities perfect for business use, offering many advantages to those who incorporate them. But what does VoIP mean? For those wondering what VoIP means – it stands for “Voice over Internet Protocol”, also known as “IP telephony”. This technology

Read More »
What is an Apple AirTag and how to use it main image

What is an Apple AirTag & How do I use it?

If you’re all about Apple, you’ve probably wondered: “what is an AirTag” exactly, “how does it work” or “how to use an AirTag?” We’re here to answer all of that and more, including its main components and key features – and, for a limited time only, we’re giving 8 lucky winners the chance to get their own for FREE: DON’T

Read More »
Top 10 best mobile phones for business use

Best Phones for Business 2023: Our Top 10 Mobiles for Work

In the growing age of digitisation, it’s essential to supply your employees with the best phone for business to enhance workplace productivity. Keeping up with the latest trends can be tough, but not staying up to date could cost your business money. Luckily for you, we’ve compiled our official list of the Top 10 BEST phones for business for 2023.

Read More »
New Apple iPhone 14 Plus review, specs, features and comparison

Why Choose the iPhone 14 Plus – Is Bigger Really Better?

It’s finally here – the Apple iPhone 14 Plus was announced during the September Apple Event, released on October 7th and looks to offer a great alternative to the Pro & Pro Max models. However, compared to the rest of this new Apple smartphone series, many are left wondering what the real difference is… Outside of a larger screen &

Read More »
Black Friday 2022 business mobile phone and sim only deals banner
Mobile phone tips

Black Friday SIM Only & Mobile Deals 2022 – What’s coming?

UPDATE: Our BLACK FRIDAY 2022 BUSINESS DEALS are now on – save up to £1,363 on our bundles this sales season. View our deals now, before they’re gone for good! As of Oct 6th: Save some money with our Black Friday 2022 Deals on Mobile Phones and SIM Only plans… The biggest bargains of the year are almost upon us,

Read More »
Latest iOS 16 software update and new features of 2022 with iPhone 14 cutout

Latest Apple iOS 16 Update & New Features

Apple’s iOS 16 update for 2022 has arrived, bringing with it a host of new features, functions and improvements. Initially announced on June 6th during the WorldWide Developers Conference (WWDC); the first public beta was released in July 2022 and closely resembled the iPadOS 16. The best part about this? It’s all FREE and compatible with a huge number of

Read More »
All new Apple iPhone 14 models and colours release announcement banner

New Apple iPhone 14 Series Release

Apple is calling the iPhone 14 “their most advanced smartphone to date” – read on to learn all the specs and features of all four models; from the Plus to the Pro Max.The new Apple iPhone 14 Series now has an official release date. Last March, the iPhone SE 2022 was teased and later released. Now, on September 7th, Apple

Read More »