Martin Lewis has warned how millions of holidaymakers could be stung by unexpected mobile roaming costs for only using a minute of data abroad.
Mobile firms were previously banned from charging extra fees to use your UK allowance - calls, texts and data - while holidaying in the EU.
This now no longer applies because the Brexit transition is over - and many of the major network providers have already reintroduced these roaming costs.
It means millions of families now face an additional cost when holidaying in the EU - on top of the rising cost of living.
But in a report published today, Martin Lewis ’ MoneySavingExpert has warned Brits to be aware of how each company defines their “daily” charge.
Have you been caught out by roaming fees? Let us know: mirror.money.saving@mirror.co.uk
EE describes a day use in the EU as anything up to 11.59pm UK time, the same day. So if you sign up at 11.58pm, you would only get a minute's worth of data for your money.
Vodafone charges £2 which lasts 24 hours from first use in the EU - but in the rest of the world, it charges £6 for roaming and this ends at 11.59pm in the capital of the country being visited.
Three customers are charged £2 a “day” which is also 24 hours from first use. The network provider also offers £5 a “day” data passport for unlimited data in the UK and 89 destinations - but only up to 11.59pm UK time.
Some smaller piggyback networks have introduced charges too.
Virgin Media O2 is the only network giant still offering roaming at no extra cost - although it has changed its “fair use” policy, which is separate to roaming fees.
“Fair use” caps the amount of your UK data allowance you can use for free while roaming in Europe.
Mobile firms were allowed to set “fair use” caps before Brexit.
Martin Lewis, founder of MoneySavingExpert, said: "I've no faith in mobile firms to self-regulate.
“When we left the EU, they promised not to reintroduce European roaming charges… yet most of the big networks have broken that promise.
"So our report calls on Ofcom to not trust voluntary promises – we need to reintroduce the formal, compulsory consumer protections.
"And it's time too, to define time. We need to ban a daily roaming fee charged for use 'up to 11.59pm' without even mentioning in which time zone.
“Instead, we recommend all providers must define a roaming 'day' as a 24-hour period from first use, clearly explain that in the arrival text, and alert customers at least an hour before the daily charges end."
An Ofcom spokesperson said: "Ofcom is currently considering the options for future roaming protections for customers, looking at the risk of consumer harm and how to best protect customers in this area.
“We will take these findings into account as part of this process."
How to cut your mobile phone bill
If you've got a holiday booked and you're worried about roaming costs, Uswitch has shared five top tips to cut your phone bill.
To save your data allowance, use hotel and café Wi-Fi connections whenever possible. You can also enable Wi-Fi calling or use services such as Whatsapp to make audio calls without using your minutes.
- Download any maps, shows, films and music before travelling to avoid data costs abroad.
- You may not have the same data allowances abroad as do in the UK. Check your fair usage policy to avoid paying more.
- Sometimes even receiving a voicemail on holiday can cost you. Call up your network provider before you travel and get it switched off.
- If you’re with a provider that has roaming charges it’s worth considering buying a one-month SIM-only deal that will cover you for your time away.
