This SIM-only deal from iD Mobile is the best we’ve come across this Prime Day. In the midst of Amazon’s annual two-day sales event, smartphone retailer Mobiles.co.uk has also joined the fray, dropping prices across a wide range of handset and networks. And right now you can pick up a 12-month unlimited data SIM with iD Mobile for just £11 a month .

Coming in at a total cost of just £132 by the time your contract ends, you really won’t be able to find a better unlimited SIM deal than this anytime soon.

Get unlimited data for £11/mth

There is a slight caveat, though. This SIM-only deal comes as part of Mobiles.co.uk’s cashback offer, which requires you to send in your mobile phone bill at months 4, 6, 8, 10, and 12 of your contract and claim £16.80 back each time. This is a bit of a faff, but it’s still well worth signing up to, especially since it saves you £84 over the duration of the 12-month contract.

As for iD Mobile, it has a bit of a reputation as a no-frills mobile network, offering packed data contracts for very little money. The network supports 5G – this unlimited SIM can connect to the new mobile network – and in our review , we found it offered better 5G speeds and received fewer Ofcom complaints than some of its competitors in Ofcom’s most recent customer service survey.

Get unlimited data for £11/mth

If you don’t already own a 5G smartphone, or you’re in the market for a handset upgrade, then we’ve rounded up the very best 5G-capable phones you can buy right now, including devices from Apple, Samsung and OnePlus. If you’re a Prime member, you can currently pick up the Galaxy S21 for as little as £514 for a limited time, too.

Craving more savings? Check out our regularly updated list of the best Prime Day discounts and bargains , including huge price drops on laptops, smart speakers, TVs and kitchen appliances.