Green Flag is warning that unsuspecting UK drivers could be subjected to substantially higher fuel prices while travelling on major holiday destination roads.
The breakdown provider says some petrol stations are charging an extra 1.9p per litre compared with the average service station price.
Scottish petrol stations have some of the most expensive options with the lowest priced fuel available around Kinross services in Perthshire and Abington services in South Lanarkshire priced at 130.9ppl, followed by Happendon Services in Lanarkshire, where the lowest available prices at 125.9ppl – much more than the national average of 116.4ppl.
The four worst offenders have no other petrol station within a five-mile radius.
Green Flag says Cumbria has a 15% difference in the petrol prices available at different stations. For example, some stations charge 131.2ppl while others only charge 114.3ppl.
Other areas affected include Membury services (123.7ppl) and Stafford services (121.9ppl). These are all destinations that are located near to a main motorway that drivers will likely be using to reach a final holiday destination including the M1, M25, M6 and the M40.
Lucy Davies, spokesman at Green Flag, said: "This is the last bank holiday before Christmas, so we want to ensure that everyone is able to enjoy the long weekend to the fullest and not have to shell out for overpriced fuels.
"Nobody wants to be caught out with costs they weren't prepared for. Green Flag urges drivers to avoid costly fuel prices by researching the roads and ensuring they find the cheapest fuel they can."