For All-Round Value: Feature-Packed Monthly Bundles
Many users prefer the convenience of a monthly bundle that includes a set allowance of data, calls, and texts for a fixed price. These no-contract deals offer great value for money.
Lebara Mobile: A consistent frontrunner in the value category, Lebara offers a variety of affordable 30-day plans. A popular choice is their £5 plan which typically includes a generous amount of data (often around 5GB), alongside unlimited UK minutes and texts. Lebara also stands out for its inclusive international minutes to select countries, making it an excellent option for those with friends and family abroad.
iD Mobile: Powered by the Three network, iD Mobile provides competitive monthly bundles with the added perk of data rollover. This means any unused data from one month is automatically added to the next, ensuring you get the most out of your allowance. Their deals often feature a good balance of data and unlimited calls and texts for a low monthly cost.
SMARTY: Another provider using the Three network, SMARTY is known for its simple and transparent "no-nonsense" plans. They offer a range of data options at competitive prices, all with unlimited UK calls and texts. A key feature of some SMARTY plans is their "data discount" where you can get money off your next plan for unused data.
For the Data-Hungry: Generous Allowances Without the Commitment
If you're a heavy data user who streams, games, and browses frequently, several PAYG providers offer substantial data packages without tying you into a long-term contract.
giffgaff: Operating on the O2 network, giffgaff's "goodybags" are monthly bundles that can be changed or cancelled at any time. They offer a wide spectrum of data options, from smaller affordable packages to larger data allowances for more demanding users.
VOXI: Owned by Vodafone, VOXI's plans are geared towards younger users, with many of their deals including "Endless Social Media", meaning you can use apps like Facebook, Instagram, WhatsApp, and more without eating into your main data allowance. They also offer competitive data packages for general use.
Three: For those who need truly massive amounts of data, Three's Pay As You Go packs can be a great option. They frequently offer large data bundles at competitive prices, making them a strong contender for heavy data users.
Freedom and Flexibility: The UK's Best 30-Day SIM Card Offers for September 2025
For those who crave flexibility and value from their mobile plan, the UK market for 30-day SIM-only deals is more competitive than ever. These rolling one-month contracts offer the perfect solution for anyone wanting to avoid a long-term commitment, whether you're a heavy data user or just need a plan for occasional use. Here's a roundup of the top genuine 30-day SIM card offers currently available.
Best for Light Users and Budget-Conscious Consumers
For individuals who use their phone for calls, texts, and a small amount of data, there are several pocket-friendly options that don't skimp on quality.
Lebara Mobile continues to be a strong contender in this category. Operating on the reliable Vodafone network, a standout offer includes 5GB of data for just £4.90 a month. This plan also boasts unlimited UK minutes and texts, making it an excellent all-round package for light to moderate users.
For those who need even less data, iD Mobile, which utilizes Three's network, presents a compelling deal of 20GB of data for £6 a month. This offers a significant data allowance for a very low price point on a 30-day rolling contract
Best for Mid-Range Data Users: The Sweet Spot of Value
This category caters to the average user who regularly streams music, browses social media, and uses maps on the go.
A highly competitive offer comes from SMARTY, powered by the Three network. They are offering a generous 50GB of data for only £8 a month. SMARTY is known for its straightforward and transparent pricing with no credit checks.
Another excellent choice is VOXI, which runs on the Vodafone network. Their 80GB plan for £10 a month is a fantastic deal, especially for social media enthusiasts. A key feature of VOXI plans is "Unlimited Social Media," meaning you can use apps like Facebook, Instagram, WhatsApp, and more without it eating into your data allowance.
Best for Heavy Data Users
For those who are constantly connected, streaming high-definition content, and gaming online, these high-data and unlimited plans offer peace of mind.
Three offers a substantial 120GB of data for £12 a month on a 12-month contract, but they also have competitive 30-day options for those who need flexibility. It's worth checking their website for the latest one-month rolling deals which often provide significant data for a reasonable price.
For truly unlimited data, giffgaff, which uses the O2 network, provides an "Always On" goodybag. While speeds may be reduced after a certain high usage threshold, it offers the freedom of not having to worry about data limits for a competitive monthly cost.