Martin Lewis has given mobile phone customers an eight-week warning ahead of a price hike in April. 

The Money Saving Expert founder warned that up to nine million people could potentially be out of contract and could be overpaying on their phone deals. 

The eight-week warning comes after Lewis told ITV viewers of his Money Show last week that mobile and broadband firms would be increasing their prices due to the latest 10.5% CPI inflation announcement.

The financial journalist explained that this is what mobile and broadband firms base their prices on with many of them not stopping there and often adding a further 3% to 4% on top.

Lewis urged customers to check their contracts and 'act NOW' ahead of the price hike in April.

Martin Lewis shares three steps to follow amid 14 per cent mobile price hike

On Tuesday's programme, the savings expert told viewers: "What you need to do to check, in most cases, is free text INFO to 85075 on your current phone that should tell you whether you have termination fees to leave your contract.

"Sometimes they can't do it, but it's worth checking."

"Last week I told you broadband and mobile bills are going up 14 per cent in April for most of the big firms," Martin added.

"What I want you to do first is I want you to check if you're out of contract. Over 9 million of you are and are overpaying.

"If you're out of contract there are actually some of you - outrageously and this should not be allowed - who got a contract with a handset and once you paid the handset off, they keep the price at the same level so you're still paying the with-handset price even if you're no longer using it."

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The broadcaster continued: "If you want to keep your number, text PAC to 65075 on your old phone, they will send you your PAC code and you use this with your new provider as a way to keep your old number.

"Of course you could use this as a way to haggle with your existing provider."

Martin Lewis also explained that there are only four networks in the UK - EE, O2, Three and Vodafone with the rest "piggybacking on their signal." 

Lewis continued: "Some comparison sites will let you do a comparison limiting to the signal that you get, so you may be able to save money and stick on your signal.

"I'm not saying it will be exactly the same service - these are different firms, you might not get WiFi calling, you might have to pay for voicemail, you might not get 5G, you might not be able to tether.

"But the point is, if you're staying where you are solely because you like your signal, why not give one of the piggyback providers, if they're cheaper, a go as well?"