A new study carried out by the RAC Foundation ranked a number of fuel retailers in terms of their average prices for a litre of petrol, and found Morrisons to have the lowest price for fuel.
The research found that Morrisons charged an average of 136.9p a litre for petrol and just 145.5p for diesel.
In stark comparison, the most expensive fuel retailer was Shell, who charged 142.6p a litre for petrol and 151.2p for diesel.
The data suggests that refueling a 55-litre family petrol car is usually at least £3 cheaper at Morrisons than Shell.
The RAC Foundation has also ranked BP as the second most expensive, charging an average of 140.8p per litre for petrol.
While Esso sells petrol for an average of 139.5p, Texaco 138.7p, Applegreen 138.0p, Jet 137.9p, Tesco 137.9p, Sainsburys 137.3p, and Asda 137.2p.
While petrol stations at supermarkets appear to offer the most economical fill-ups, the RAC has advised drivers to explore various options in attempting to find the best prices.
Steve Gooding, the RAC Foundation director, told PA news agency that prices are often influenced by competition in the area.
He said: “While this data shows that on average supermarket-branded fuel is most keenly priced, as might be expected, motorists would still be best advised to shop around because the data also shows that prices are influenced by local competition.
“The transparency this data provides will give both motorists and ministers a better picture of the petrol and diesel market. Topping this price league table should give retailers cause for concern.”
While Shell states on its website that prices vary between refueling stations “for a number of reasons”.
They blame the fluctuation on the cost of buying and transporting the fuel, and running each site.
It adds: “Shell is only legally able to control prices at company-owned sites, which constitute approximately half of the Shell-branded network in the UK.
“The other half of Shell branded service stations are owned by independent dealers who set their own prices.”
The news comes just after research from the AA, which discovered that some Brits are forking out £7.50 less than the average driver each time they pull up to refuel.
In a partnership with the Competition and Market Authority’s fuel price transparency scheme, the breakdown cover company have compiled a list of the best deals across the nation.
It was reported that motorists in Colerain, Northern Ireland, were ranked the luckiest – pocketing around £7.48 at a Sainsbury’s station boasting unleaded petrol at 140.9p per litre.
This comes in a staggering 13.6p less than the UK average which currently sits at an eye-watering 154.5p.
Data sourced through The Competition and Markets Authority (CMA) also found that petrol stations can vary from 50p a litre across Britain, and diesel ranges by 45p.
As it stands, nearly 4,000 fuel retailers have signed up to the programme and uploaded their current fuel costs.
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