Do I need a new phone and SIM for 5G?

5G mobile networks are already live in many countries, and more and more people are starting to buy 5G services. We see a new network technology roughly every ten years, and every time there is a new technology, people have some basic questions surrounding the SIM and devices. In this post, we aim to answer as many devices and SIM questions as possible so that you can focus on enjoying 5G rather than searching for answers to basic 5G questions.

What does 5G mean for an average phone user?

We have been using 4G services for many years, and our phones seem to be doing their job just fine, so why do we need new technology, and why are we expected to pay a lot of money for it? 5G is the latest generation of mobile networks enabled by a new technology New Radio – NR. The G in 5G stands for Generation, and 5 represents the generation number. So 5G is the fifth generation of mobile networks, which is the next step after 4G LTE networks. 5G will play a key role directly and indirectly for most of us, but as a phone user, the most important aspect may be the higher download and upload speeds that 5G brings to the table. 5G NR technology can provide average download speeds of around 150 Mbps (Reading/UK/June 2021) which is already higher than the average UK home broadband speeds. If you work from home frequently and have issues with your home broadband, 5G on your phone can provide a great backup solution if you want to use it as a hotspot. The other, more interesting way of using 5G is as your main home broadband. 5G mobile broadband is called eMBB (Enhanced Mobile Broadband), and you can use that by getting a 5G router.

Does 5G require a new phone?

Yes. 5G uses New Radio technology (NR) which is not the same as LTE. As a result, if you want to access 5G services, you need a new device. So, if you currently have a 4G phone, it will not allow you to access 5G, and you will need a 5G phone. The same goes for broadband routers, so if you currently use a 4G LTE mobile broadband router, you will not be able to get 5G on that and will need a 5G router to access 5G services. It is important to note that all mobile devices are backwards compatible but not forward compatible. That means if you have a 5G router and if you don’t have great 5G coverage in your area, you will still be able to get 4G LTE on that router.

Will my 4G SIM work on 5G?

One of the most frequently asked questions on 5G is about the SIM card and whether or not you need a new SIM to access 5G services? It is probably a confusing topic because different mobile operators have different stances on it. Interestingly all the different answers are technically accurate, making the topic slightly more confusing than it should be. So, let’s simplify it here. The short answer is that you do not need a new SIM for 5G, and your existing 4G SIM will work in your 5G phone; however, there may be some limitations. The SIM card used in 4G networks is based on the same specifications that the 3G SIMs (USIM) were, making them backwards and forward compatible.

The SIM card is basically an integrated circuit and is a combination of hardware and software. Your mobile subscription’s privacy and security aspects get more advanced as new technologies come, and 5G also adds new levels of security. So, if you use a 4G SIM in your 5G phone, it will technically still allow you to access 5G, but the levels of privacy and security will depend on what programme sits on the SIM. As a result, you may find mobile operators in the UK, who will advise you to get a new SIM for your 5G phone, but you may also find operators who will advise you otherwise. At a personal level, I would prefer to get a new SIM for my 5G phone to be on the safe side.

Does 5G SIM work on any phone?

If you have a SIM card advertised as a 5G SIM, it will still work in older mobile phones, but you will not be able to access the 5G network on older phones. SIM cards from 3G onwards are backwards and forward compatible, so a 5G SIM will work in a 4G phone, but you will only get access to 4G, 3G and 2G networks when using a 4G phone. The other practical thing to keep in mind is to have the right SIM size for your device. Most operators provide triple SIMs nowadays, which include standard, micro and nano SIM sizes. So, for example, if your phone only takes a micro SIM, you want to make sure that you have the micro SIM size available.

What are the requirements to access 5G?

Before you start your journey with the 5G services, here is a quick checklist to make sure you tick all the required boxes:

  1. 5G coverage
  2. 5G mobile phone
  3. 5G tariff
  4. 5G ready SIM

5G Network Coverage

The first thing you need to do is to find out whether your mobile operator has decent 5G coverage in your area or not. The best way to do that is by contacting the operator or checking the coverage map on your operator’s website. If you find out that your home or work location where you want the 5G services are not yet covered, the operator may be able to give you an idea of the timelines if you contact them. If you live in the UK, you can use the following links to check the mobile network coverage in your area.

Vodafone UK network coverage

EE network coverage

O2 network coverage

Three network coverage

If your current mobile service provider is not listed above, you may be using the services of an MVNO. MVNOs are Mobile Virtual Network Operators (e.g. Tesco Mobile) that use mobile networks of Mobile Network Operators (e.g. O2) to reach your phone. Here is a Wikipedia link to find out which MVNOs in the UK are using which mobile operators. The “Host network” column shows the mobile network operators (MNO).

5G Device

5G uses a new technology called New Radio (NR), so you will need a 5G-NR capable mobile phone. Without a 5G capable device, you won’t be able to access the 5G networks. A 5G device is backwards compatible, so it will allow you to access 5G as well as 4G (LTE, 3G (UMTS/HSPA) and 2G (GSM/EDGE) networks.


As 5G is still new and the coverage isn’t as mature in most parts of the world, your mobile operator may not have 5G available on all tariffs. It may be that they sell both 4G and 5G tariffs separately so that people who live in areas without 5G have a cheaper option in the form of 4G tariffs. If you want 5G, make sure to check your plan before buying. When 5G becomes more common, you may get 5G on all tariffs as a standard. That depends on each operator as to how long it takes and how they want to sell 5G services in your country.


You may or may not need a new SIM card to access 5G services on your 5G phone. As explained above, some operators advise you to use the same 4G SIM, but some other operators advise customers to buy a new 5G SIM. Therefore you should check with your operator.


You will need a new 5G compatible (5G Ready) mobile phone to access the 5G networks because your old 4G phones will only be able to connect you to 4G, 3G and 2G networks. You may also need a new 5G ready SIM card for your new 5G phone unless your mobile operator advises you otherwise. Mobile phones are backwards compatible, so your 5G phone will still allow you to automatically connect to 4G, 3G and 2G networks if you are in areas with limited or no 5G coverage.

Here are some helpful downloads

Thank you for reading this post, I hope it helped you in developing a better understanding of cellular networks. But sometimes, we need some extra support especially when preparing for a new job, or studying a new topic, or maybe just buying a new phone. Whatever you are trying to do, here are some downloads that can help you:

Students & fresh graduates: If you are just starting, the complexity of the cellular industry can be a bit overwhelming. But don’t worry, I have created this FREE ebook so you can familiarise yourself with the basics like 3G, 4G etc. As a next step, check out the latest edition of the same ebook with more details on 4G & 5G networks with diagrams. You can then read Mobile Networks Made Easy which explains the network nodes e.g. BTS, MSC, GGSN etc.

Professionals: If you are an experienced professional but new to mobile communications, it may seem hard to compete with someone who has a decade of experience in the cellular industry. But not everyone who works in this industry is always up to date on the bigger picture and challenges given how quickly the industry evolves. The bigger picture comes from experience which is why I’ve carefully put together a few slides to get you started in no time. So if work in sales, marketing, product, project or any other area of business where you need a high-level view, Introduction to Mobile Communications can give you a quick start. Also, here are some templates to help you prepare your own slides on product overview and product roadmap.

Scroll to Top