Currently you have to phone your current mobile provider when you want to switch to a new firm, and request a ‘porting authorisation code’ (PAC) to give to your new provider if you want to keep the same phone number.

But the communications regulator Ofcom says the need to speak to your provider can be one of the main hurdles to switching, with firms often trying to persuade customers to stay.

So from Monday 1 July, you’ll be able to cancel your contract by sending a single free text, and be switched within one working day – regardless of whether you have a contract or pay-as-you-go phone.

Once you’re out of your minimum contract, mobile providers will also be banned from charging you for the remainder of your notice period after you’ve switched (which is typically 30 days), putting an end to paying for your old and new contract at the same time. You will, however, still be charged early termination fees if you leave before the notice period of your existing contract.

All of the major mobile networks including Vodafone, O2, EE, Giffgaff and Three have confirmed to MoneySavingExpert.com that they’ll have implemented the new service by Monday.

See our 30 Cheap Mobile Tips for more on cutting the cost of your mobile phone.