If you're setting off in the car this weekend, think carefully about where you stop for a break.
Motorway service stations are bumping up the price of snacks by up to four times the normal price, with the south west forking out the most.
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A basket of food and drink items that costs £6.11 in a supermarket can be as much as £15.78 on the motorway, and a pack of sausage rolls can be four times as much.
Undercover shoppers from car insurer Admiral visited 21 service stations and bought a bottle of water, a bottle of Coke, a ham sandwich, sausage roll, a bag of crisps, a Cadbury's chocolate bar and a bag of wine gums.
They also investigated the cost of hot food and fuel, scoping out the cost of a latte, cheeseburger and bacon butty and the cost of a litre of petrol and diesel.
And they found that drivers face a 'snack tax' everywhere, with the most expensive basket costing £15.78 in the south west. Even the cheapest basket - in the North West - came in at £12.58.
Surprisingly, London was only in seventh position, with the basket costing £13.86.
"Families risk spending over the odds if they leave buying food, drink and fuel until they reach a service station. A few seemingly harmless items in the basket could add up to a lot more than they bargained for, adding greatly to the cost of a day-trip or holiday."
When it comes to fuel prices, it's west Midlanders hit hardest, with a litre of petrol costing £1.35 and a litre of diesel at £1.36. Consumers filling up in South Wales, meanwhile, pay just £1.19 for petrol and £1.22 for diesel.
"A stop-off on a long journey or en route to the airport is often not factored into people's budgets and this is where unexpected costs mount up. The simplest way to save those pounds is by planning ahead. Those who do have to buy snacks or fuel at motorway service stations will find they're held to ransom," says Hargreaves.
"Filling up the car at your best value local petrol station and stocking up with journey essentials before you set off will ensure your journey is smooth and you don't get weighed down with the heavy cost of a motorway sausage roll."
The cost of the snack basket around the UK
1. South West: £15.78
2. Yorkshire: £15.74
3. North East: £15.53
4. West Midlands: £15.14
5. East Midlands: £15.02
6. South Wales: £15.00
7. London: £13.86
8. South East: £13.85
9. Scotland: £12.79
10. North West: £12.58