EE is to hit millions of customers on its monthly mobile contracts with a 4.1% price rise next month.

The telecoms firm is contacting customers saying its monthly contract costs will go up in line with December's Retail Prices Index (RPI) inflation figure, from 30 March.

The increase will affect all pay-monthly mobile customers unless they joined EE or upgraded after 6 February 2018. Pay-as-you-go customers won't see prices go up.

For help on cutting the cost of your mobile bill, see our 30+ Cheap Mobile Tips.

I'm mid-contract - can I leave penalty-free?

Unfortunately you can't. Mobile firms CAN increase prices mid-contract in line with inflation without you being able to leave penalty-free, as long as they include a warning about this in their terms and conditions - and EE does. So you can't just up and leave.

There is a rule set by telecoms regulator Ofcom that means you can escape your contract penalty-free if you can successfully prove you've suffered "material detriment" as a result of a price increase - but it would be very hard to prove an RPI increase had caused this.

Make sure you note down when your contract is due to end, and start looking for new deals about a month before.

What if I'm out of contract?

If you're out of your minimum contract term you can leave without paying any penalty, and there's a good chance you can save by switching to a better deal - especially if your original contract deal involved paying for a handset.

Most should NEVER pay over £10/month for mobile use, particularly given two-thirds of mobile users consume less than 3GB/month. See our Mobiles section and Cheap Sim-only Deals guide for full help on finding a cheaper deal elsewhere.

Alternatively, if you're willing to stick with EE, this is a chance to haggle a better deal – especially as you have the right to leave penalty-free.

See our Mobile Haggling guide for detailed tips, but here are a few to get you started...

  • Benchmark the best deal elsewhere so you ask for a realistic discount.
  • Get through to the retentions (sometimes called disconnections) department. They have the most power to slash costs, as their job is to keep you.
  • Use charm and be friendly. Aggression or anger will just put their back up.
  • Don't panic if they call your bluff and say they'll disconnect you.

Other firms increase prices mid-contract too

Unfortunately, EE's unlikely to be alone in increasing prices. Many of the major firms increase prices in line with figures published in February or March each year, based on the RPI.

Last year most Vodafone, EE and O2 pay-monthly customers saw a 2.5%-3.2% increase in their bills, while Three increased pay-monthly bills by 2.6%. We'll keep our eyes peeled for rises from any of the other firms and will cover them as soon as they're announced.

What does EE say?

An EE spokesperson said: "Like many service providers, our pay-monthly plans increase by RPI annually, and this year customers on our most popular plan will typically see an increase of 85p a month.

"We're currently contacting our customers to remind them this will take effect from 30 March 2018."