Compare unlimited data SIM only deals

Fewer people than the market sells to. Ofcom's pricing research found 39 percent of pay monthly customers take a plan with over 50GB of data, yet only 5 percent use that much in a month. Unlimited earns its keep in three situations: you tether a laptop through your phone regularly, you have no home broadband and the SIM is your household connection, or you stream video for hours away from Wi-Fi. If none of those is you, check our data guide before paying the premium; a 30GB plan costs a fraction of the price.

Unlimited means unlimited on every plan we list, but the terms around it differ. Some networks publish fair use policies for sustained heavy use, and a few cap how much of your allowance can be used for tethering or set speed limits on their cheapest tiers. The deal card's full details section lists each plan's perks and conditions, so open it before you commit rather than assuming every unlimited plan behaves the same.

Once every plan has the same allowance, the differences that matter are price, contract length and what happens to the price mid term. Sort by monthly cost and check the price rise line on each card: some networks schedule April increases, while others fix the price for the whole term. Coverage decides the rest, because an unlimited plan on a network with one bar at home is unlimited in name only. Check the signal at your address on our UK mobile coverage map, and remember smaller brands share the big four networks' masts.

Before settling on unlimited, look one shelf down. Plans with 100GB or more cover all but the heaviest use, and the price gap between big-allowance and unlimited plans opens and closes as networks reprice. When the step is small, unlimited is cheap peace of mind; when it widens, the 100GB plan quietly wins for almost everyone. Untick Unlimited in the data filter here and the table shows you the neighbouring allowances at today's prices, so the comparison takes seconds rather than guesswork. If you have never measured your usage, your last three bills settle the question faster than any rule of thumb.

An unlimited SIM in a phone with a hotspot, or in a dedicated router, can genuinely replace a fixed line for lighter households. It suits renters, students and anyone between homes, because there is no installation and no landline. Heavy streaming households will feel the difference at peak times, so compare what a fixed broadband deal costs at your postcode before deciding; sometimes the wired option is cheaper than the SIM.