Drivers are being urged to avoid motorway services to save up to £19 on fuel this Bank Holiday weekend

This August holiday is expected to be the busiest on the road in more than a decade.

Nearly 20 million car journeys are expected to be made during the three-day weekend, with many motorists flocking to petrol stations to fill up before or during their journey.

But with motorway services charging sky-high prices, consumer organisation Which has revealed that drivers who take a short detour can find significantly cheaper fuel nearby.

This is the biggest saving motorists can make by going off-piste this weekend.

The RAC expects Britons to make 19.2 million holiday journeys between Friday and Monday, meaning the roads will be busy for motorists throughout the weekend.

The figure, based on a survey of 2,128 adults in the UK, is the highest ever and dates back to the 2015 summer holidays.

Yesterday (Saturday) was predicted to be the busiest day of the weekend with 3.7 million planned journeys. However, today another 3.1 million will be added and tomorrow another 3 million, according to the motorists’ group.

Many of these vehicles will use highways to reach their destination as quickly as possible.

But anyone who decides to stop at petrol stations along the British motorway network will be faced with far too high prices.

While most drivers are aware that highway service refills are much more expensive, many are unaware of the average prices in the area, far away from these busy main roads.

Which? and PetrolPrices.com have calculated how much cheaper petrol could be if motorists were prepared to drive a little bit off the motorway.

The company has calculated the biggest fuel cost savings drivers can make on popular routes this weekend.

The biggest savings this weekend if you are willing to take a small detour from the highway

The listed petrol prices are calculated based on the fuel prices published on 16 August. There is therefore a good chance that the prices have changed this weekend.

However, price differences between motorway service stations and those closer to towns and in rural areas remain similar, although fluctuations may occur due to the higher prices charged at service stations.

The cases mentioned below are examples of situations where gas prices are cheaper miles away – and sometimes even closer to the tourist attractions people want to visit.

The figures show that people heading to Cornwall’s beaches and wanting to fill up near Taunton Deane petrol stations could save around 30p per litre if they exit the M5 and stop at the Sainsbury’s petrol station just off junction 25.

Filling an average 55-litre tank of petrol at this supermarket is £16.50 cheaper than at a motorway service station. If you have to fill up en route and on the way back, it will cost you £33.

The same goes for those driving to the popular shopping destination of Bicester in Oxfordshire, where the outlet stores at Bicester Village attract large numbers of shoppers during the bank holiday.

Instead of filling up at the Cherwell Valley stations on the M40, motorists can save 34p per litre by filling up at the Esso station or the Tesco supermarket near the shopping area on Oxford Road.

Some of the examples cited by Which? show the cheaper destination for fuel at Costco locations. These are only available to those with a Costco membership, starting at £33.60

Natalie Hitchins of Which? said: ‘Motorists heading away on holiday this long weekend would be wise to check petrol prices before they set off.

‘Go to gas stations that are not located along the highway to save money, as they are known to be very expensive.

‘It’s also worth checking prices when you’re not on the motorway, as our research shows that in some areas of the UK you could save around £5 per tank if you look carefully.’

Big savings locally if you shop around

While you’ll get the biggest fuel savings at discount gas stations rather than highway services, drivers can also save big by shopping locally.

If you live in an area where petrol station prices are close to the national average of 142 pence per litre, you can use a site like this: PetrolPrices.com to see if travelling a little further could lead to cheaper fuel costs.

You don’t have to drive too far, but you might want to plan your next reorder for a trip that takes place near a cheaper area.

For example, at the time of writing, if you live in Redhill, Surrey, local unleaded petrol prices are around 143.9p. But if you travel just 5 miles south and cross the county border into Horley, West Sussex, you’ll benefit from Asda’s unleaded petrol price of just 135.7p.

That’s around £4.50 cheaper per full tank of 55 litres of unleaded. Fill up twice a month and that’s the equivalent of a saving of £108 a year.

Can you also save on charging electric cars?

While you can save money by comparing different gas stations, the same cannot be said for charging electric cars.

Most public rapid charging stations in the UK are around the same price, while many petrol stations have large charging bays for electric cars.

So if you need to charge your car, there’s no reason not to do it at a gas station along the highway.