Unlimited data SIM



If you are a heavy data user on your mobile, watching streaming services and sport for hours on end, then the chances are you want a SIM plan that gives you as much data as possible. Ideally, you want an unlimited data SIM that puts no caps on what you can do with your phone in terms of your access to the internet and on how much data you use. That means you can stream, play games and do whatever you want online without having to worry about running out of data or racking up expensive charges.The good news is that they do exist.
Last update: April 2022

It’s important to understand how much data you use, among a variety of other factors when deciding if you will choose a SIM only deal. A choice of SIM providers offer unlimited SIM deals but there is a caveat. While deals do offer unlimited data, there is often a fair usage clause. What this means is that some networks will apply a policy to stop people abusing their unlimited plans. That’s because these unlimited plans are intended for personal use only and sometimes people do use their data for commercial purposes. These fair usage caps are very generous, usually between 650 and 1000GB a month, and when you consider average usage is about 3GB of data, then for all intents and purposes it is unlimited. Unless you are streaming hi-def video content all day everyday or using your phone as a hotspot for a whole gang of friends 24/7, you probably won’t exceed the fair usage cap. However, you should also be aware that some networks put speed restrictions in place as part of their fair usage policy. So, if you have used a huge amount of data in a month you might find that your connection is slowed.

Which SIM only deal would be best for unlimited data?

Worrying about how much data you are using on your phone is no fun. Whether it’s for work or just for pleasure, being limited to a certain amount of GB per month and having to keep your eye on the counter can be annoying. Worse still, what if you go over your allotted data and end up having to pay a small fortune for the extra data you use? So how much do unlimited data SIM deals cost? And which suppliers offer them? We’ll attempt to answer all these questions and more in this guide to unlimited data SIM cards. Not all networks offer unlimited data in the UK. However, those that do include:

Supplier Contract length Texts and minutes Cost per month
Lebara 1 month Unlimited £15
EE 24 months Unlimited £20
ID 12 months Unlimited £18
Virgin Mobile 12 months Unlimited £28
Vodafone 12 months Unlimited £20

Even if your chosen network does not currently offer unlimited usage, then you might still be able to get a deal with a large amount of data, making it unlikely you will go over. Remember that the average monthly use of data in the UK is just 3GB. Some suppliers, like Tesco Mobile, offer SIM deals with as much as 100GB of data. That means you would have to use about 30 times the average to run out.

Remember that unlimited data deals are much harder to come by with SIM only packages than with mobile contracts including a phone. Unlimited SIM only deals vary in both price and in terms of what else you get with the contract. However, the cheapest deals tend to start around £16 a month from networks including Three and Smarty. Whether these are the best deals for you depends on your needs.

How much is an unlimited data SIM?

As mentioned above, the cheapest SIM only deals start at around £16 a month. With these packages you also get unlimited minutes and texts. From there costs go up to around £30 a month for some of the bigger networks, but these deals tend to come with other things in the package such as access to 5G networks and subscriptions to streaming services included.

Which mobile phone network is best for unlimited SIM deals?

This really depends on what you are looking for from your SIM deal. For example, if you want a basic SIM package with unlimited calls, text and data, you can get one for around £16 a month from both Three and Smarty. The Three contract is for 12 months with the Smarty deal having no fixed term.

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Is it true that unlimited data is really unlimited?

As we mentioned above, although networks do say their SIM deals offer unlimited access, this is often subject to a fair use policy to prevent abuse of these kinds of agreements. Each network has a different approach to what their fair usage policy is and how that might affect your connection

Below you can see a table which shows the fair usage policies of the major suppliers.

Network Restrictions on unlimited data plans
BT Mobile Solely available to existing BT broadband and TV customers
EE 1000GB per month fair usage limit
giffgaff After monthly usage of 40GB, speed restrictions apply
Lycamobile After monthly usage of 9GB, speed restrictions apply
O2 650GB per month fair usage restriction
Smarty 1000GB per month fair usage limit
Three No fair usage policy
Virgin Mobile Solely available to existing Virgin Media broadband and TV customers
Vodafone Speed restrictions on Unltd Lite and Unltd plans
Voxi Fair usage policy and speed restrictions apply, limit unspecified

Who has true unlimited data?

If a deal says the data is unlimited then this is essentially what it means, within reason,. The fair usage terms and conditions are only there to protect the network should someone want to take excessive advantage. Most of the fair usage limitations come in way above 500GB of data use a month. This is hundreds of times what the average user requires each month. So, unless you need mobile internet to stream high resolution movies round the clock or to run an entire office off your mobile hotspot (which is generally against the terms of individual use) then the data is effectively unlimited.

All of the major suppliers who offer unlimited data SIM deals will have this written into their terms and conditions to offer some protection against abuse by customers. So, as long as you are planning on reasonable individual use, you should have all the data you could ever need.

Can I trust smaller, less well known networks? Is the service as good?

Everybody knows the big name mobile providers on the market. Networks like Vodafone, Three and BT Mobile are household names. But what about the smaller mobile companies out there offering seemingly good deals? Can you trust them to deliver a good service?

The answer is yes you can, within reason. There are scams out there with dodgy providers luring you in with the promise of good deals but these should be fairly easy to spot. In general, they will approach you either with an unsolicited email or phone call. If you are unsure about their credentials then walk away and never hand over any money or financial details unless you are 100% sure of the company’s legitimacy.

A quick search of the internet should tell you everything you need to know. If the company has a professional looking website and they have a presence on review sites such as Trustpilot and Which? then you can be sure they are genuine.

There are lots of smaller providers who offer phone services. All of these are governed by the same legislation, overseen by the industry regulator, Ofcom. That means all providers have to abide by the same rules. Of course, that does not mean that you are guaranteed to get a good service, as the standard of customer support is up to the provider – within reason.

However, don’t always assume smaller companies have poorer customer service as it can often be more personal than the big corporations. So, if you see a deal you like and it checks out online, then there’s nothing stopping you going for it.

How do I keep my number when I get a new SIM?

When you move from one network to another you need to ask your old network for a PAC code. You then need to give this to your new network within 30 days of starting your new contract. Once you have provided them with your PAC, your new network will move your mobile number over to your new SIM.

Are unlimited data plans worth it?

The savings you can make from getting an unlimited plan will only start to accrue once you use over 10GB a month on a regular basis. If you use less than that, around the UK average of 3 GB a month, then you could probably make do with a plan with limited data, which tends to be cheaper. It all depends how you intend on using your data package.

Unlimited data can also be useful if you occasionally need large amounts. Because unused data is rarely able to be carried over from month to month you don’t build up a deposit. That means if one month you go way over on your data, it could end up costing you extra on your bill. It’s worth looking into and seeing what your average data consumption has been over the last 12 months before making your decision.

How do unlimited SIMs work?

Unlimited SIMs work in the same way as normal SIM cards. Sign up to a deal, pop the SIM card into your phone and you can get started. Your data is unlimited apart from the fair usage policies which we have detailed above. But other than that, it all works in the same way as your existing SIM.

Which provider has the best prepaid unlimited data plan?

Unlimited data deals tend to be on contracts rather than pay as you go deals. That means you pay a monthly fee for the duration of your contract and get the benefits of unlimited data.

Pros and cons of unlimited data SIMs

The benefits of getting an unlimited data SIM is that there are no real restrictions in place for how much data you use. That means you don’t have to worry about going over your limit or extra charges being incurred. A SIM only deal means you can use it in any phone, which also makes contracts much cheaper.

The downsides are that you don’t get a phone with your SIM only deal so will need to provide your own handset. Unlimited plans also tend to cost more than plans with a set data limit.

What to look for in unlimited data SIM plans

It’s important to check the terms and conditions of any contract. Find out what the fair use terms are as this gives you a clear picture of exactly what unlimited data means for your contract.

Can I use my unlimited data abroad?

It depends on the terms of your contract. Many providers allow you to use data abroad with no extra charges. However, there is often a time limit on how long this lasts. Again, it’s all about fair use. In your deal there might be a clause saying that if you are out of the country for more than a certain time period, say three months, then extra charges can be levied for data usage.

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Can I get a mobile contract with unlimited data?

Yes, unlimited data is now a common feature of both phone and SIM only phone contracts.

Does unlimited really mean unlimited?

Most suppliers will have a fair use clause in the contract which limits data use in cases of abuse, but these limits are generally very high, often way over 500GB a month.

How much is an unlimited data SIM?

Deals start at around £16 a month. From there costs go up to around £30 a month for some of the bigger deals on larger networks, but these deals tend to come with other things in the package.

Can I keep my number when I get a new SIM?

When you move from one network to another you need to ask your old network for a PAC code. This will allow you to keep your current phone number.

Updated on 9 May, 2022

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