Unlimited data SIM deals

Price

The cost of unlimited data SIM plans can vary depending on the type of deal you’re on. What probably won’t surprise you is that 5G deals tend to be more expensive than their 4G equivalents, but that’s not always the case.

To see if the cost of an unlimited data deal is worth it, think about your typical usage and how frequently you’ve run out of data and had to pay to top up. Then compare the total with the cost of an unlimited data plan.

Also check whether your provider has an inflation clause that allows them to increase the price mid contract. With high inflation rates you could find your bill rising steeply if this is the case. Around a third of mobile customers don’t know whether their provider can increase their price.

Price will also depend on whether you’re getting a new phone on a monthly plan or choosing a SIM-only deal for your existing phone.

Contract length

When looking for a good SIM deal for unlimited data, decide whether you want a flexible, rolling monthly plan, or whether you’re happy to lock yourself into a longer-term deal.

We compare a range of SIM only unlimited plans, as well as monthly plans if you want a new phone. Each has a selection of contract lengths to suit your needs:

• One-month contract – these unlimited data, pay-as-you-go SIM only plans offer the most flexibility, allowing you to end your deal and swap to another after just a month. If you’re happy where you are, the contract simply rolls on. Because of this flexibility, they can be more expensive than longer contracts.
• 12-month contract – while less flexible than a rolling monthly plan, these year-long contracts often reward you with a cheaper deal for locking yourself in for longer.
• 24-month contract – these are usually offered as part of a phone plan, but you can get them for SIM-only deals too. Again, you can be rewarded with a cheaper price for locking yourself in for a longer term, but you lose out on flexibility. If a better deal comes along in a month or even a year, you won’t be able to switch without paying a fee to cancel your contract early.

Text and call minutes

Texts and call minutes are usually unlimited on an unlimited data plan. So if you’re weighing up a plan with limits against an unlimited data plan, make sure that you’ve got enough texts and call minutes to suit your needs. Checking an old bill should give you some idea of your typical usage.

Unlimited social data

If you're addicted to social media and messaging, a plan that offers unlimited social data but doesn't include video and streaming is an option. There aren't as many deals to choose from and some may cover only one or two apps, but they tend to be cheaper than all-in plans. It means you can scroll, swipe, snap, tweet, post or chat to your heart's content – or at least until any screen-time limiting apps you've installed kick in.

Freebies

Some deals will throw in a free gift like headphones, a games console or a voucher. But don't opt for a deal because of the freebie if the plan doesn't suit you.

Network

The big four networks (EE, O2, Three and Vodafone) have almost nationwide coverage, but some smaller networks may not, so it’s worth checking. It’s also worth checking which networks have local indoor and outdoor coverage – particularly if you live somewhere remote. Try the Ofcom coverage checker. It will help you see if 5G is available too.

Roaming

If you’re planning on using your phone abroad, check how any roaming charges apply to your unlimited plan. You don't want a nasty shock when you come home to discover a bill for something you thought was included.