Your browser isn't supported
It looks like you're using an old web browser. To get the most out of the site and to ensure guides display correctly, we suggest upgrading your browser now. Download the latest:

The MoneySaving Forum: join to chat & swap tips with other MoneySavers. Learn how in the Forum Introduction Guide

30+ Cheap Mobile Tips

Find the best deal and cut costs

By Nick | Edited by Steve N

Updated 9 Feb 2016

Whether your phone's superglued to your ear or you only use it for the odd call, the chances are you're massively overpaying for the minutes, texts and data that you use.

Getting a new phone can be a big financial decision, particularly if you're committing to a contract. This guide crunches the numbers and talks you through the different options – plus offers handy tips to drive down the cost of your existing mobile deal.

If you're paying more than £18/mth, you're probably paying too much

cutting down mobile costsHow much is your mobile bill each month? If you're paying more than £18/mth, then you need to ask yourself why.

£18/mth is the key benchmark because that's how much it typically costs to get yourself a decent allowance on a Sim-only deal, though of course it depends on exactly what balance of minutes, texts and data you want.

That's also what O2's Sim-only deal with unlimited minutes and texts and 4GB of 4G data costs, which should be enough for all but the heaviest of data users. It is possible to get cheaper deals if you don’t need that much though this – see full details of all our top pick tariffs below, including discounted plans for those with certain broadband providers.

In our November 2014 poll almost 25,000 of you told us how much you pay for your mobile. The results were eye-opening – a whopping 78% of those on contracts which factor in the cost of a handset (and 46% overall) shell out more than £15 a month, with an average cost of £27/mth, or £330 a year.

Of course, there are valid reasons why you may be paying more than £18/mth. These include:

  • You're paying off the cost of a handset.
  • Your credit score means you can't get a contract (though there are cheap PAYG deals too).
  • You roam abroad.
  • You're paying more for a really hefty data allowance.

If one of the above applies, then at least there's a reason for your bill being higher – though you still may be able to save.

But if you just settle for the same deal, provider and price each year, then STOP. Mobile tariffs are deflating in price, so if anything you should be paying less each year, not more.

Before you look for a new deal, ask yourself whether you REALLY need a new handset

hand setThe biggest single factor affecting the cost of your new mobile deal is whether or not you'll be paying for a new handset as well. It's important to understand that even if you get a contract tariff where the phone itself is 'free' or relatively cheap, in practice you'll end up paying for it – and generally end up paying MORE for it – through the monthly tariff.

If you already have a decent handset in good nick, you'll get a far cheaper deal if you opt for a Sim-only deal. Here you simply get the Sim card with the tariff, but no handset. (See our top picks below.)

How to find a new handset

If you DO want a new handset, first think about what features you want and will use. A useful site that allows you to compare handsets is GSM Arena. It lists the full specifications for each model so you can see at a glance if it has what you need.

Read reviews online and ask friends and family for advice on which handset might be best for you before you set your heart on any gadget. You might also consider buying a second-hand phone – check websites such as eBay* and Gumtree.

Check your current usage with a free matchmaking tool – then find the right contract

Knowing how much you use your phone and what you use it for is crucial to getting the best plan.

Match free mins, texts and data closely to your usage. If you don't, you'll go over and overpay for calls. Go under and you'll overpay on the package.

Some tariffs offer unlimited options for calls and texts, meaning unlimited calls to UK landlines and mobiles and unlimited texts to UK mobiles – other calls/texts and roaming outside the UK will cost extra. But only the heaviest users would need this amount of allowance.

The easiest way to check your usage is to simply dust off your last three to six months' bills, jot down what you use every month and then work out the average. Or if you ring your provider, it'll usually tell you – you may also be able to check online.

  • Free matchmaking tool: MobilePhoneChecker* is one of only two Ofcom-accredited mobile comparison tools (along with Billmonitor, see below). It's easy to use and the most comprehensive we've come across.

    It's recently introduced a bill monitoring feature that works out how much you're actually using each month and recommends tariffs based on this – it works with BT Mobile, EE, Giffgaff, iD Mobile, O2, TalkMobile, Tesco Mobile, Three, Virgin Mobile and Vodafone.

  • The original matchmaker: Stalwart bill-comparison site Billmonitor* compares your previous three months of bills to find the best contract or Sim-only deal based on your usage. However unlike MobilePhoneChecker, it only works with customers of EE, O2, Tesco Mobile, Three and Vodafone. It's also not quite as user-friendly as the newer player, though it gives a more detailed bill analysis.

Is it safe to give MobilePhoneChecker and Billmonitor your login details?

  • If you know what you want: Head to MoneySupermarket* where you can specify an allowance of minutes, texts and data and it'll show you the cheapest tariff for that package. Crucially, you can also search by handset and filter by cashback.

Don't forget about cashback. The mobile market is rife with a variety of discount packages, so it's important to understand the difference.

How to claim discounts and beat the cashback trap

Choose the right type of tariff: contract, Sim-only or pay-as-you-go

The number of different mobile tariffs on the market can be baffling – there are thousands of different combinations and it can be tricky to compare them on a like-for-like basis.

There are three different types of tariffs to choose from. Here's how they stack up:

Contract with handset – best for heavy users and spreading the cost

Pay monthly

With a traditional mobile phone contract you pay a monthly fee and get a handset plus an inclusive bundle with a certain allowance of minutes, texts and data.

  • Handset price is spread out – but it costs you more in the long term

  • Often better for heavy users, especially on calls and texts

  • You'll be locked in for 12, 18 or 24 months

  • No risk of running out of credit

Sim-only contract – if you've got a handset you like and want flexibility

Sim only

There are two types of Sim-only deals – 30-day rolling contracts which you are free to leave each month, or fixed term contracts, usually lasting 12 months.

  • Good if you have a handset or can afford to buy one upfront
  • Rolling 30-day contracts offer maximum flexibility
  • Often good for heavy data users

PAYG – no ties and never go over your allowance

Pay as you go

If you pay for your mobile via pay-as-you-go, you won't be tied into any contract – simply pay in advance for what you use via top-ups, online or on the phone.

  • PAYG doesn't require any credit check

  • Easier to budget

  • Generally more expensive for medium or heavy users

Swanky smartphones are NEVER MoneySaving, but if you get one, get it cheaply

smart phoneSadly, there's no way round this one – a shiny high-spec smartphone just isn't MoneySaving. But if you absolutely must get your mitts on one, it's possible to pay less and avoid being locked into a long contract if you do it right.

The cheapest way to get a new iPhone 6s or Samsung S6 is usually to buy the handset upfront, then get a separate Sim-only deal – but not everyone can afford to do this. If you can't pay upfront, then perhaps think about switching down to a cheaper model, waiting and saving up for it.

If you're going to get one anyway though, check our top picks on tariffs – plus comparison tools and useful tips and tricks – in Cheap iPhones and Cheap Samsungs.

Many providers allow early upgrades

If you're happy to stick with your current provider, then it's often possible to upgrade your handset before your current contract comes to an end.

Don't forget the cheapest deals usually some from switching provider, but if you're willing to haggle this info might be useful. The following table sets out the major providers' early upgrade policies.

How early can you upgrade?
Provider Early upgrade policy
EE (incl T-Mobile and Orange) Switch to a new phone and plan up to 45 days before your contract ends.
O2 O2 Refresh splits your monthly statement into a cost for the handset and cost for your allowance. You can pay off the handset part of your contract whenever you want and upgrade without also having to pay off the ‘allowance’ segment – you’ll just continue paying it alongside the ‘new device’ segment of the bill.
Vodafone Upgrade up to 30 days before your contract ends.
Three Upgrade up to 30 days before your contract ends.
Tesco Mobile The same system as O2 Refresh above.
Virgin Mobile No official policy on early upgrades. Its Freestyle Contracts allow you to pay off the handset and buy a new phone to use with your existing airtime contract.

Happy with your handset? Haggle down the contract costs

If you don't want to switch, and are near or past your contract's end, you're wielding a powerful weapon... your loyalty. When approaching the end of your contract, make sure you demand the very best deal possible – not just of your network, but of any out there.

The mobile world's a mature market. Everyone has a handset, so networks fight hard to win custom from elsewhere AND keep their own. If your provider won't give you a good enough deal, let it know. The aim's to get through to 'customer disconnections', which internally is often called 'retentions' as its job is to keep you. Watch Martin show Mrs MSE how to do it, with real chutzpah!

We know this method works, as you regularly tell us it does. Forumite elfy1807 says: "My contract with Orange was up and I asked them what they could do for me. I turned down two offers until I got £16/mth, 1.5GB data, unltd texts and 2,000 mins – a saving of £36/mth, that's £432/yr."

Full help on how to do this in our Haggle Down Your Mobile Bill guide.

4G gives you superfast internet – but beware of it sucking up your allowance

cutting down mobile costsNetworks claim that 4G is up to 5x faster than 3G, though Ofcom-estimates suggest that in practice downloads are only twice as fast, compared to uploads which were more than 8x quicker. The regulator also says 4G and 3G performance differs between networks, with some outperforming others.

Some operators charge more for 4G tariffs, and even if they don't, you're likely to use more data if you're on one.

So think about where you use your phone. If you're out and about a lot and will benefit from a faster connection, it may be worth it. If you mainly use it at home and work and you're able to connect to Wi-Fi there, then that often beats 4G anyway.

To get 4G you'll need a handset that's capable of getting it (many launched in the last two years can).

Happy with your handset? Take your pick of the top Sim-only deals

If you're happy with your mobile handset or are buying one upfront, then it's well worth looking at Sim-only deals as they generally offer a cheaper alternative.

Unless you're already with a Sim-only tariff provider, you'll probably need to get your phone unlocked (though Giffgaff will work if your phone is locked to O2). Our Mobile Unlocking guide has full help. Also see our PAYG top picks, including Giffgaff bundles and options for low users or those concerned about being credit-scored.

iD Mobile

500 mins, 5,000 texts, 4GB (4G): £10/mth*


Carphone Warehouse recently launched its own virtual mobile network called iD Mobile*, which runs off Three's network. It's got a huge range of plans – long-term, short-term, with handset, Sim-only – all on 4G.

Its Sim-only offerings are very competitive. Our top pick costs £10/month and comes with 500 minutes, 5,000 texts and 4GB of 4G data, It's a one-month capped ("ShockProof") contracts meaning you can limit your additional usage (and bill) to no more than £5 over the monthly contract cost.

iD Mobile also provide other plans*, its standard ("Go-To") plans allow any unused data to rollover to next month, these tend to be a bit more expensive however. Its roaming ("Takeaway") plans allow you to use your allowance in 29 countries. Here are a few more of its capped ("ShockProof") plans.

  • £5/mth. With this ID deal* you get 250 mins, 5,000 texts, 500MB.

  • £7.50/mth. This is a good value deal from ID*. You get 250 mins, 5,000 texts and 2GB for just £7.50/mth. Data will drop to 1GB/mth after 12mths.

  • £15/mth. If you opt for this £15/mth ID deal* you get 2,000 mins, 5,000 texts, 6GB. Data will drop to 3GB/mth after 12mths.

  • £20/mth. Pay for this ID deal* and you get 2,000 mins, 5,000 texts, 10GB.

  • One-month contract.
  • Runs off the Three network.
  • If you exceed your allowance, it's 10.24p/MB for data, 40p/min for calls to UK mobiles or landlines and 14p per text.
  • Tethering isn't allowed with this network.
  • You'll be credit-checked – see our Credit Scores guide.
The People's Operator

Unltd mins & texts, 6GB (3G): £12.49/mth*


For the data-hungry out there, The People's Operator* has a £12.49/mth Sim-only tariff that gives unlimited minutes and texts and a generous 6GB of 3G data – the cheapest we've seen with this allowance. It's worth bearing in mind that 3G data it isn't as fast as 4G, fine if speed isn't a concern.

The People's Operator, launched in 2012, is a piggyback network running off EE's signal. The company has mixed reviews on customer service in the past, but it's taken steps to improve since. It will also give 10% of your monthly spend (pre-VAT) to a charity of your choice – a nice touch.

If this one isn't suited to your usage, TPO offers a range of other plans* with lower usage. They all give a discount in the first month, but after that aren't the cheapest for what they give, especially when compared with the deal above.


  • 30-day rolling contract; contracts terminate at the end of the calendar month in which you give notice.
  • Runs off the EE network.
  • Calls to UK mobiles & landlines are included. Calls to 084/087 numbers cost extra, see call costs.
  • Use up your allowance and you'll have to pay 3p/MB. See full charges.
  • You won't be credit-checked, though it'll carry out a basic ID check.
  • Offers can sometimes be beaten by cashback sites, it's worth checking them first.

Unltd mins, 4GB (4G): £18/mth*


This deal with O2 via – available in Micro* and Nano* Sim size (check which you need) – should be more than most would need. It's the cheapest plan if you want unlimited minutes and a fairly hefty 4GB of 4G data. The only reason you'd ever need to pay more than £18/mth is if you use an awful lot of data. If that's the case, the BT or Three Sims below may be more suitable.

This deal locks you in for a 12-month contract but if you don't want to be tied in, you can get the same deal on a 30-day contract for £20/mth. O2 offers a variety of different plans* at different price points but these generally aren't as competetive as the ones featured in this guide.

  • 12-month contract.
  • Calls and texts to UK mobiles and landlines included; 084/087 numbers are more.
  • If you exceed your data allowance you'll need to buy a bolt-on, from £3 for 100MB.
  • O2 is one of the networks that increases prices in line with inflation each year.
  • Tethering is permitted.
  • You'll be credit-checked – see our Credit Scores guide.
Life Mobile

3,000 mins, 3GB (3G): £10/mth*


Life Mobile* (now owned by EE), is offering a cracking deal via uSwitch to new and existing customers out of contract.

At £10/month (usually £11.95/month) it comes with 3,000 minutes, unlimited texts and 3GB of 3G data – the cheapest we can find for the allowance it gives. It's on a 30-day contract; the network piggybacks on EE's signal.

The company's had mixed feedback in the past, so it's worth being aware of this and doing your own research. It does look like customer service has been improving lately however, and this deal's so competitive – with only a one-month commitment – we think it's worth considering.

It offers a range other plans too, which are also competitive, they're all one-month contracts and 3G-only:

A nice additional feature is the ability to cap your monthly bill to prevent being charged outside your allowance beyond a set amount each month. This is pre-set to £5, but can be changed to between £1 and £30.

  • One-month rolling contract.
  • Runs off the EE network.
  • Additional charges are £1/day (up to 250MB) for data, 35p/min and 12p/text.
  • You won't be able to use your phone abroad unless you activate roaming.
  • Tethering is permitted.
  • You won't be credit-checked.
BT Mobile

Unltd mins, 20GB (4G): £16/mth for BT b'band customers*


Telecoms giant BT* offers three 12mth Sim-only plans. If you're a BT broadband customer, you'll pay £5/mth less for each of the tariffs than everyone else, which makes them among the most competitive around (though BT's broadband prices can often be beaten so it's not worth swapping providers just to get the Sim).

All the plans come with 4G data, access to the BT Sport app, a £50 discount on selected handsets from the BT Shop*, and access to more than five million BT Wi-Fi hotspots.

Here are the options:

  • £5/mth for BT b'band custs (£10/mth otherwise). 200 mins, unltd texts, 500MB.

  • £10/mth for BT b'band custs (£15/mth otherwise). 500 mins, unltd texts, 2GB.

  • £16/mth for BT b'band custs (£21/mth otherwise). Unltd mins and texts, 20GB.

    Until Mon 15 Feb – you can get a £40 iTunes or Amazon gift card with any of these Sims. Claim via this link.

If you stop being a BT broadband customer at any point your monthly mobile tariff will jump by £5.

The £50 discount code may come in handy if you were planning on buying a handset anyway, but always check if you can find it cheaper elsewhere. You'll get a code in the confirmation email of your BT Mobile Sim order. You must redeem the code against one of the eligible handsets by 31 March 2016; there'll be a delivery charge of at least £3.49.

  • 12-month contract.
  • Runs off the EE network.
  • Calls and texts to UK mobiles and landlines are included. Calls to 084/087 numbers cost extra.
  • Monthly spending can be capped, from a starting point of £5 over your tariff.
  • Use up your allowance and you'll have to pay 35p/min and 10p/MB. Full costs here.
  • You'll be credit-checked – see our Credit Scores guide.

Unltd 4G data, 200 mins: £20/mth*


If you're looking for a cheap deal with lots of 4G data, Three's £20/mth Sim-only tariff via uSwitch* gives you 200 minutes, unlimited texts and unlimited 4G data on a 12-month contract. If you'd rather the freedom of a rolling contract, then it's £23/mth*.

Three also offers a variety of other 12-month Sim-only plans*. Here are a few examples:

  • £11/mth. 200 mins, unltd texts, 2GB.

  • £16/mth. 600 mins, unltd texts, 4GB.

  • £19/mth. 600 mins, unltd texts, 8GB.

Alternatively if you want to go all out, you can get unlimited minutes, texts and 4G data on a 12-month contract for £30/mth, or £33/mth on a 30-day contract.

  • 12-month contract.
  • If your minute allowance runs out you'll be charged 35p/min.
  • Three's 'Feel at Home' lets you use your allowance in 18 countries at no charge.
  • Tethering is permitted within your data allowance (up to max 12GB/mth).
  • You'll be credit checked – see our Credit Scores guide.

In some cases it can actually be cheaper to get a 40% APR loan than a handset on contract

If you don't have the readies to pay upfront for a handset, think long and hard before tying yourself into a lengthy contract instead – even if it offers you the phone 'free' or at a much-reduced upfront cost. Not only will the cost of the handset be wrapped up in the monthly tariff, you'll nearly always be paying a significant amount extra over the course of the contract.

When we crunched the numbers in January we calculated that in some cases it'd actually be cheaper to buy a handset direct with a 40% APR two-year loan (typical contract length) than take a contract. (Of course, we're not suggesting you do that.)

We worked out how much extra users would pay with six of the UK's biggest mobile providers if they were to get a 16GB iPhone 6s or a Samsung Galaxy S6 on a two-year contract, as opposed to buying the handset directly and taking out the same network's equivalent Sim-only deal.

The table below displays the 'effective APR', which is the interest rate you could afford to pay on a loan to buy the handset upfront plus get the equivalent Sim-only plan on the same network and it STILL be cheaper than taking out a similar contract deal from each network.

'Effective APR' of popular phones
Network iPhone 6s (16GB) Samsung Galaxy S6
Vodafone 40% 27%
EE (incl T-Mobile & Orange) 38% 26%
O2 31% 18%
Virgin Mobile (1) 30% 30%
Three 19% 25%
Tesco Mobile 12% 24%
(1) New Virgin Media customers. Figures rounded to the nearest %. Table correct as of 12 Jan 2015.

Mobile providers say that a contract isn't a loan (so they don't usually display an APR) but effectively it is one as you're credit checked. Even if a network offers you a deal where you can pay the cost of the handset and your tariff off separately you're likely to be paying a premium.

Quick question:

Could I get the handset on a 0% credit card instead?

Top PAYG deals – for low users or to avoid being credit checked

cutting down mobile costsIf you're a very low user, can't pass a credit score or just want to be totally in control of how much you spend, then opting for a pay-as-you-go (PAYG) deal might be a good option.

Why does my credit score matter? When you apply for a mobile contract (including Sim-only contracts) you're usually credit scored (because the company is spreading the cost of the handset over the contract, so for the firm, it's effectively a loan). If your credit history's poor then there's a chance you will be rejected and won't get a contract.

If this happens, don't despair – you still have options. You can choose between Giffgaff (which doesn't credit score you because you're technically prepaying rather than signing up for a contract) or another PAYG provider. Alternatively you could always try boosting your credit score.


Tiered bundles incl 500 mins, 2GB (4G): £12/mth*


Sim-only provider Giffgaff* offers PAYG bundles called Goodybags, which start from £5/mth and go all the way up to £20/mth. It made all its Goodybags 4G and changed some of their allowances on 2 September.

Here's a summary of its bundles (view full info here*). All include unlimited Giffgaff-to-Giffgaff calls and texts. The cheapest bundles have very low allowances, so make sure it's enough before you buy.

  • £5/mth* Goodybag. 100 mins, 300 texts, 100MB data.

  • £7.50/mth* Goodybag. 250 mins, unlimited texts, 500MB data.

  • £10/mth* Goodybag. 500 mins, unlimited texts, 1GB data.

  • £12/mth* Goodybag. 500 mins, unlimited texts, 2GB data.

  • £15/mth* Goodybag. 1,000 mins, unlimited texts, 4GB data.

  • £18/mth* Goodybag. 2,000 mins, unlimited texts, 6GB data.

  • £20/mth* Goodybag. Unlimited mins, unlimited texts, "Always On" data.

With "Always On" data you'll get the first 6GB at 4G speeds, after which you'll be put on a restricted speed of 256kbps (which is around 1/24th the speed of 3G) between 8am and midnight everyday until your Goodybag expires.

If you do run out of minutes or data you can purchase another Goodybag if you don't want to wait until your current one expires. Note though – if you do this, you'll lose any remaining allowance you had on the existing Goodybag.

  • Buy bundles on a 30-day rolling basis.
  • Runs off the O2 network.
  • Out-of-allowance charges are 10p/min and 6p/text and 2p/MB until your Goodybag expires, after which standard PAYG pricing applies.
  • No credit check.
  • You won't be able to go over your allowance without buying another Goodybag (unless you have credit).


Pay-as-you-go: 3p/min, 2p/text, 1p/MB (4G)*


The 321 tariff from Three* does just what it says on the tin – it's a simple and cheap tariff, charging on a purely pay-as-you-go basis. It's a cracking deal for occasional mobile users, as it's by far the cheapest PAYG rate on the market.

It's a Sim-only deal, so you'll need an unlocked or Three handset to put the Sim into. It'll only work in 3G-compatible handsets, so much older non-smartphones are a no no.

How much is it? Top up online with £5 minimum (£10 in store) and it costs 3p/min for calls, 2p/text and 1p/MB for data (though the first 150MB after each top-up is free).

You'll lose credit after six months if you don't use it – but use your phone occasionally and it'll stay on permanently.

Can I add extras? If you want extras, such as 500MB data bundle, you can add these whenever you need to (see the Three website for info).

There are a range of other PAYG providers to choose from. Here are their pay-as-you-go rates:

PAYG rates compared
Three* Asda Mobile Giffgaff* EE* O2* Vodafone*
Calls 3p/min 8p/min 10p/min 30p/min 30p/min 30p/min
Texts 2p/text 4p/text 6p/text 12p/text 14p/text 14p/text
Data 1p/MB (4G) 5p/MB (3G)

2p/MB (4G)

N/A1 £1/day2 (3G)

£2/day3 (3G)

1. Cannot pay for data as you go, must buy a data add-on/pack. 2. Up to 50MB/day. 3. For the first 50MB, 10p/MB thereafter.

The following table shows what you'll get from each on a £10 bundle, which gives better value than paying as you go. They're more like Sim-only plans in that you get a fixed allowance each month, the difference being you'll still have to top up if you want to use more or buy another bundle.

£10 PAYG bundles compared
Giffgaff* Asda Mobile EE* Vodafone* Three O2*
Calls 500 mins 600 mins 150 mins 150 mins 100 mins 250 mins
Texts Unltd texts Unltd texts Unltd texts Unltd texts 3,000 texts 1,000 texts
Data 1GB (4G) 1GB (3G) 500MB(4G) 500MB (4G) 500MB (4G) 500MB (4G)

Get a 'granny in a glovebox' – grab a cheap emergency phone

emergancy phoneA ‘granny in a glovebox’ phone is great to stash in your car as an emergency second mobile, to give to your kids or if you only need to use a phone very occasionally.

One of the cheapest we've found is the unlocked Nokia 105 from Carphone Warehouse for £19.99. Since it's unlocked, you can pick up a PAYG Sim from any network – bear in mind though that Three Sim cards won't work with it as it's a 2G (older, non-smartphone) handset.

If you are planning on going with Three, at the time of writing there's a compatible refubished Samsung S5611 Utopia for £20.99. Otherwise, we you can opt for the Nokia with another network such as Giffgaff.

If you're after a phone with web access, one example of a cheap smartphone is the Sim-free Alcatel Pixi 3 from Tesco Direct for £39 (+£3 p&p, or free Click&Collect).

Mapping tool shows mobile signal strength – check before you commit to a contract

The major providers all have maps indicating what coverage they offer. But telecoms regulator Ofcom has its own Mobile Coverage Checker which goes beyond what the networks' own tools do.

Before committing to a contract, check signal strength in the places you use your phone most, eg, at home and at work. Having no coverage isn't sufficient grounds to return your phone (though normal consumer rights do apply), so it's your responsibility to check.

How good is the tool?

How do I use it?

What are my rights if I'm unhappy with my mobile coverage?

It very much depends. Under the Consumer Contracts Regulations, if you ordered online or over the phone you can cancel your mobile contract up to 14 days after you sign up, for any reason. But if you buy in-store or a problem arises after that, it can be tricky – see more on what you can do.

Stay secure – lock your handset AND your Sim

Most people instinctively lock their smartphones these days, in case they get nicked. You don't want those with light fingers getting access to your personal data and other sensitive info. (For how, here are screen-locking instructions for iOS (the Find My iPhone feature is also useful), Android and Windows Phone.)

Yet even if your handset is locked, if someone steals it there's nothing to stop them removing your Sim and using it in another phone. Some have had huge bills racked up on their contracts after their (locked) phones were stolen.

To prevent this, you can lock your Sim with a four-digit PIN, so whenever it's put into a new handset (or in some cases, such as with iPhones, when the phone it's in is restarted) service won't be available until it's unlocked.

You can find instructions online for locking your Sim on an iPhone, Android phone (may vary by handset) or Windows Phone. Your Sim may already have a default PIN (even if it's not activated) which you'll need to enter to change it – contact your network for this.

Note: if you incorrectly enter your PIN three times you may need a Personal Unblocking Key (PUK) code to enable your Sim again. You should be able to get this from your network.

If your phone's stolen... report it to the police and let your network know as soon as possible. This is important to prevent unauthorised use of your service, and may also be critical for insurance claims.

Make sure you've the right size Sim

Sim cards come in three sizes – standard, micro and nano – and which one you'll need depends on your handset. All iPhone models from the iPhone 5 onwards use a nano Sim, as do some of the latest Android phones such as the Samsung S6.

Many other Android phones, including the Samsung S5, Note 4 and Windows phones, take micro Sims, which are slightly larger than nano Sims. The iPhone 4 and 4S also take micro Sims.

Standard-size Sims haven't been used in smartphones for the past few years and not many take them anymore. If you're upgrading to a newer handset, most networks can very easily swap your Sim card for the right one if you ask.

Consider the contract length – don't end up in a two-year 'relationship' you can't afford

If you sign up for a contract you're essentially committing to a phone company (and often a handset too) for the length of the contract.

This means you must think carefully about your budget and if you can afford the ongoing monthly payments. The amount of time varies between deals a few last 12 months, but most high-end smartphone contracts now span 24 months.

Before you sign up to a contract make sure you're happy to be locked in for the minimum term. If you want to leave early then it's likely you'll have to pay termination fees which cover the cost of the contract.

Some providers have started to offer tariffs which make it easier for customers to upgrade early. (See below for full details.)

Always calculate the contract's total cost

Whether you're taking out a 12-month or 24-month contract you should always look at how the total cost compares. You can do this by multiplying the monthly cost by the length of the contract, then adding in the upfront cost.

For example, let's say there's an upfront cost of £39, plus a monthly charge of £15 multiplied by 18 months. The total cost of the contract would equal £309.

Don't ditch your digits! Get a PAC to keep your number when you switch

Transferring – or 'porting' – your old mobile number is easy when you switch phone provider. All you need to do is get your PAC (porting authorisation code) from your existing provider, then give it to your new one.

Most networks will ask you to request a switch of number before you start using your new phone, but some will still do it after the new contract is set up. It usually only takes a couple of days.

You can't port your number within the same network, so if you take out a deal on your existing network that's intended for new customers (ie, that isn't specifically an upgrade) you won't be able to keep your old number. When you terminate the old contract you'll lose it.

The only way to get the new deal and keep your number would be to get yourself a free pay-as-you-go Sim from a different network, port your existing number across to it, then port the number again to the new contract once it's been set up.

Recycle your old handset and earn £100s

If you're getting a new handset, recycle the old one and you could earn £100s, depending on the make, model and condition of the phone.

There are a raft of companies willing to recycle your phone for cash, yet be warned the differences in what they'll offer are huge. At the time of writing, for example, a 16GB iPhone 6 could fetch anything from £220 to £271.

To help, use our unique MobileValuer tool it instantly tells you what each of the main mobile recycling sites will pay. You can get up to £400 for some handsets. Of course others are virtually worthless, but it's worth a quick try.

Once you agree to sell, most companies send you a Freepost bag for your phone. You post it, then they give you the cash.

These sites are all about instant prices though. If you're prepared to put in a little more effort and flog your handset on eBay, you can often beat their prices. See our full 30+ eBay Selling Tricks guide for more info.

'Piggybacking' means you do have a choice of mobile provider even if you can only get signal with one network

If you live somewhere with rubbish phone signal and you can only get coverage on one or two networks, fear not. You may assume your choice of provider is limited but switching to a 'piggyback' deal can allow you to cut bills without your signal dropping.

There are only four UK networks EE, Vodafone, Three and O2. All the others piggyback on and buy space from one of these four. For example, Tesco and Giffgaff are on O2, Asda is on EE and TalkMobile is on Vodafone.

You're still using the same network as the larger company so the reliability's the same, but it's normally cheaper or you get more for your money. There are lots of piggybackers to choose from see our full mobile piggybacking guide & list to see which you can move to, paying less with the same signal.

Don't sign on the dotted line until you've used our 'before you buy' checklist

Signing up to a new mobile deal, especially if it's a contract that locks you in, is a big commitment. Most contracts lock you in for 24 months, which means you won't be able to get out of paying for it during this time. That's why we've come up with six MUST-CHECK points to consider before you sign on the dotted line.

  • Check coverage. Ofcom's Mobile Coverage Checker lets you see how strong a signal you should expect for calls/texts and data on each network across the country. It's well worth checking before signing up.
  • Don't forget about credit checks. If you have a poor credit history then there's a chance you could be rejected for a contract. When you apply for a mobile contract the provider will check your score to see how reliable you are at paying bills on time. Before applying, check your credit score, and if necessary see our tips for boosting your credit score.
  • Consider the contract length and its total cost. Do the maths to make sure you're getting a good deal.
  • Do you need mobile phone insurance? Depending on the cost of replacing your handset it might be worth getting mobile phone insurance. See our Cheap Mobile Insurance guide for full info.
  • Keep your number when you switch. It's easy to keep your number but you'll need to get your PAC code.

Know how to unlock your phone so you have maximum choice of provider

Unlocking your phone means you can use any network's Sim, which gives you the freedom to switch providers and hopefully cut your mobile phone bill.

Some handsets are unlocked when you buy them – usually if you purchase them directly from the company that makes them or from a middleman store such as Carphone Warehouse. But if you got your handset from a network it will usually be 'locked' to that specific provider.

You may be able to unlock your phone for free, depending on your network and the type of handset you have. If you can't then providers will charge you for an unlocking code – prices vary but it usually costs between £10 and £20. See our Mobile Phone Unlocking guide for full details.

Decide whether you need mobile phone insurance – and if you do, get it from as little as £5/mth

The best mobile phones no longer just make calls. They're our diaries, contact books, cameras, games consoles and more – so lose it, break it or have it nicked and there can be tears.

Insurers play on this fear with hefty prices and unnecessary cover. Yet you can get cheap smartphone and iPhone insurance from £5/month.

But do you really need insurance? Deciding whether to get a policy comes down to the fact that you know yourself better than insurers will.

  • How likely are you to lose or damage your phone? If your mobile's been permanently attached to your hand and you haven't broken or lost it in the last 10 years, the chances you'll lose or break it in the future are slim. If you have smashed or misplaced a phone in the past, however, it might be worth considering. It's important to know yourself, then you can play the odds.

  • Are you worried about mobile phone theft? Theft of mobile phones is falling, according to a Home Office report – but these numbers are often questioned because it's believed a high proportion of mobile theft is never reported. If you live in a crime hotspot then insuring your phone for theft might be a good idea.

If you decide that insurance is for you, don't just get what is offered by your network provider, think about a specialist insurer, self-insuring and/or covering your phone on your home insurance or a package bank account. Full info and best buys in Cheap Mobile Phone Insurance.

Beware of exceeding your data allowance – it could add £60/yr to your bill

If you use up your data allowance before the end of each month it could end up costing you. The majority of networks will ask you to pay an extra chunk of cash if you want to extend your allowance. This could add £60 (or more) to your annual mobile bill.

There are a number of ways to avoid this:

  • Use Wi-Fi whenever possible – see below for how to do this.
  • If you really need more then speak to your network about upping your allowance – this may cost but it'll be cheaper than exceeding your limit and you can try to haggle.
  • Make sure any apps you use aren't eating up your allowance.

Be sure you understand what ‘unlimited’ includes

Many mobile contract and Sim-only deals offer ‘unlimited’ minutes, texts or data, but it’s important to understand what that actually covers.

Unlimited minutes are to UK landlines and mobiles, and unlimited texts to UK mobiles – other calls/texts and roaming outside the UK may cost more. Always make sure you know exactly what’s covered and what you’ll have to pay extra for.

Similarly some networks place 'fair usage' caps on their 'unlimited' tariffs, (confusingly) limiting the allowance you actually get. Where a provider does this on a plan we write about we'll say so, but it's worth checking yourself before signing up.

Use free Wi-Fi spots to save on data costs

If you've a smartphone, you may find you can keep costs down by taking a smaller data plan and using free Wi-Fi while you're out and about.

mobile wifi

There are Wi-Fi hotspots dotted all over the UK (and abroad), many of which are free. McDonald's, Starbucks and Wetherspoons and Walkabout pubs all offer free wireless internet. It's also worth checking My Hotspots (UK-only, quite limited).

Find out more about free Wi-Fi hotspots and how to save on mobile data costs in the Free Wi-Fi and Mobile Broadband guides.

Avoid roaming charges – don't get hit with a huge holiday bill

mobile holiday billHead abroad and your mobile provider may hike prices massively, and even charge for receiving calls as well. Yet you can substantially cut the cost by using networks' hidden deals or by getting a specialist Sim card to use overseas.

Get more info on the cost of using your phone abroad and the various specialist Sims available in the Mobile Roaming guide.

Cut the cost of calling abroad – or do it for free

free holiday callsCalling someone overseas from your mobile often costs big bucks, yet it doesn't have to be that way. Making free internet phone calls (VoIP) sounds complicated, but it's very easy, especially if you have a smartphone.

Our guide to Free Web Calls has details on apps that let you call for nowt, how to make free calls from your computer and the best way to call friends who don't use VoIP.

If your phone is faulty, then it's the responsibility of the retailer to fix it

All the usual consumer rights apply when you buy a mobile phone. The phone must be of satisfactory quality and fit for purpose. (See the Consumer Rights guide for more.)

Remember here, the responsibility lies with the retailer, not the manufacturer. So if you discover a problem after buying a new phone, it's the retailer who must sort the problem for you.

If the fault is minor, it's reasonable to accept a repair. If not, you're entitled to a refund, although the retailer can deduct an amount for the use you've already had.

If you think you've been mis-sold your mobile contract then you have rights

mobile wifi

If you think you've been mis-sold, either by the mobile phone company or by a company selling on its behalf, you need to know your rights. Your first action should be to inform the provider and follow its complaints procedure. Or, use free complaints-handling company Resolver, which will help you with your claim.

After that, if you are still unhappy and feel the issue has not been resolved, Resolver will appeal on your behalf to one of two Alternative Dispute Resolution schemes – Ombudsman Services: Communications and CISAS – which act as middlemen between mobile phone providers and users.

You have rights if your mobile phone provider hikes prices mid-contract

If you're locked into a phone contract and your provider decides to hike prices, then you may be able to get out of the deal without paying a penalty.

Over the past few years mobile phone firms have started introducing annual price hikes, usually in line with inflation, which affect customers who are mid-contract. This used to mean the price of your contract would rise and there was nothing you could do about it.

However, in January 2014 Ofcom changed the rules around mid-contract price rises. It confirmed that anyone with a landline, broadband or mobile contract should be allowed to leave if their provider introduces unilateral mid-contract price rises.

Ofcom said price increases to a recurring monthly subscription are "materially detrimental" to users. Providers now need to give at least 30 days' notice of any such rises and allow users to leave the contract without penalty (see the O2 to hike its prices MSE news story).

These rules apply to any NEW contract taken out after 23 January 2014. Unfortunately they don't apply retrospectively though, so companies can still hike prices for contracts taken out before this date.

"Inflationary costs" exception

If you've switched providers recently, check whether you're owed cash

If you've switched mobile provider within the last six years and still had money remaining in your account when you left then it's possible to claim it back.

Many providers don't automatically refund credit when you leave, so it's worth checking. See our Reclaim Phone Credit guide for full details.

Some providers charge for voicemail services – deactivate this to avoid charges

Many assume voicemail is always free. Yet exceed your inclusive minutes or call from abroad and voicemail costs up to 40p/min on contracts out of allowances. On PAYG it can cost up to 35p/min. Keep track of how many minutes you have left or turn it off entirely, especially on holidays. Simply call your network and get it to deactivate voicemail.

You could try an app such as HulloMail. Download it to your smartphone and it replaces the voicemail system on your phone, using Wi-Fi or 3G to retrieve messages. It can be patchy if you're in an area with limited signal, but it's worth considering if voicemail is costing you big.

How to complain about your mobile provider

The mobile industry doesn't have the best customer service reputation and while a provider may be good for some, it can be hell for others. Common problems include limited network coverage, slow data speeds, unexpected charges and more. It’s always worth complaining to your provider first, but if you have no success, then…

Free tool if you’re having a problem

This tool helps you draft your complaint and manage it too. It’s totally free, and offered by a firm called Resolver which we like so much we work with to help people get complaints justice.

If the complaint isn't resolved, Resolver will escalate it on your behalf to the free Ombudsman Services (or CISAS if you're complaining about Virgin Mobile).

Important: if your issue is about a voucher or incentive that was part of an MSE Blagged deal, then instead just let us know by emailing as that’s usually quicker.