Free Sim cards Cheapest for data, texts & international calls

Mobile networks are doling out free no-contract Sim cards: used right they can get you unlimited texts, free Skype calls, cheap calls and even 2for1 cinema tickets.

So either switch to them or pop them into any unlocked handset (see unlocking info below) for specific tasks.

Also see: The Full Cheap Mobiles guide and Haggle Down Your Contract

GiffGaff* Cheapest for high usage

Mobile provider GiffGaff, while officially a pay-as-you-go Sim-only provider, offers top up bundles which are as good, if not better, value than some contracts. You can get 1,500 inclusive minutes and unlimited texts per month, as well as unlimited data, when you buy the £25 GiffGaff goody bag.

This is a great deal for folk who use their phones a lot, but can't get or don't want a contract deal.

You can get a free Sim card, but you'll need to top-up by at least £10 to activate it. As it's a pre-pay deal, there is no credit check required and no contract lock-in. Plus sign up via the links and when you top it up with £10, you'll get £5 free credit.

You can use your existing handset but only if it's unlocked. Read the Mobile Unlocking guide if your phone needs unlocking.

How to get it incl £5 free credit: Get a free GiffGaff* Sim card online and choose the goody bag that best suits your needs.

GiffGaff* Cheapest for web

GiffGaff is also by far the cheapest if you're looking for free mobile internet as all its goody bags over £15 include unlimited free web. See if it stacks up for the number of calls and texts you make using comparison MobilePhoneChecker* (the only comparison that includes it so far). Plus sign up via these links and once you've topped it up with £10, you'll get £5 free credit.

How to get it incl £5 free credit: Order a free GiffGaff* Sim online (it should arrive within 1-3 days), then activate it and top up by at least £10 to get your free £5 credit.

Need a handset? GiffGaff is a Sim-only provider so perfect for those looking for a cheaper option to go in a handset they've already got. You phone will need to be unlocked to use GiffGaff though (read about Mobile Unlocking in the guide).

Tesco Mobile* Best for high texters

Tesco offers 5,000 texts for £5 when you opt into its text bundle, making texts just 0.1p per message.

How to get it: Get your free Tesco Sim* online - just fill in the form. Then call 282 from your mobile and follow the prompts, or add it via your online account.

The bundle will automatically renew every month until you stop it. There is a fair usage limit of 400 texts per day, if you go over this (or you use all 5,000 texts in one month) you'll be charged the standard rate of 10p/text.

O2 Best for international calling

If you frequently call friends or family abroad, O2's free International Sim can cut costs dramatically. Get the Sim and top up £15 every month and you can call landlines in India, China and Poland for 1p/min, as well as unlimited free calls and texts to other O2 mobiles.

There's a raft of other countries in the 1p/min bracket for landlines, and rates to mobiles overseas are also competitive (see all international rates).

If you tend to call the same people abroad, and you've both access to a computer, it may be more economical to use an internet phone service like Skype instead (see the Voip guide for full info).

How to get it: First go through to the free O2 Sim page, select the International Sim and fill in the form to apply. When the Sim arrives, top it up by £15 to get the cheap rates.

Orange Get 2for1 cinema tickets

Orange’s free Sim comes with £5 of completely free credit when you top up with £10. What's more, all Orange mobile customers can get 2for1 cinema tickets just by texting Orange. If you've an unlocked handset, just pop it in every Wednesday when you're heading to the cinema (see the Orange 2for1 guide for full info).

The Canary package gets you 100 free evening and weekend minutes to UK mobiles (plus 11 free texts) with a £10 top up, and the Racoon package gets you lower standard rates (14p/min instead of 25p/min).

Even if you don't plan to use this as your main Sim, it's worth grabbing for the cinema deal.

How to get it: Fill in the online application form to get your free Orange Sim. Register it and top up £10. For 2for1 tickets, just text 'Film' to 241. It'll text you a code to use when you get to the cinema. This costs 35p/text.

Is your handset unlocked?

When you buy a new phone, chances are it'll be locked to the network you bought it on, and if you try to put another network's Sim card in it simply won't function. So to take advantage of most of the offers below (ie ones that aren't from your handset's network) you'll need to unlock it.

Unlocking most modern handsets will require you to buy a code from your network, though some older handsets can still be unlocked for free. For full details on the ins and outs of unlocking, read the full Mobile Unlocking guide.

Get a bit of cashback too!

It's possible to earn cashback when signing up for a few of these Sims too. Needless to say, the amounts you'll earn are pretty small, but if you're already a member of a specialist cashback website it is an option.

For more info on how this works read the full Cashback Sites guide beforehand.