The RAC’s August Fuel Watch report has found that petrol prices in Northern Ireland were 5p per litre lower than the UK average in August, while diesel was 7p per litre cheaper.
After two months of rising pump prices, the RAC reported that the average cost of petrol nationwide was down by 0.39p per litre in August, while diesel was down 0.72p per litre.
On average a litre of petrol cost 134.64p and a litre of diesel cost 142.2p.
Supermarket fuel prices saw similar decreases in August, with petrol prices down by 0.72p to 131.26p per litre, while diesel prices were down 0.3p to 138.81p.
In Northern Ireland, the average petrol price was 127.9p per litre in August. Diesel cost 134.5p per litre.
Costco stations in Northern Ireland charged 125.9p per litre for petrol and 133.7p per litre for diesel, but require a membership.
Simon Williams, head of policy at the RAC, said: “While it’s good news that two months of rising fuel prices have come to an end, it’s disappointing that high retailer margins are preventing drivers from benefitting from lower prices.
“The Competition and Markets Authority’s latest report confirms that retailer margins are far higher than they were historically, and that competition remains weak.
“Our analysis of pricing data confirms the latter, with just a handful of forecourts appearing to compete heavily on price, with the exception of those in Northern Ireland where drivers enjoy far cheaper fill-ups than in any other corner of the UK.
“This is no doubt a source of ongoing frustration for many of the nation’s motorists.”
The Competition and Markets Authority (CMA) has criticised the ‘weak’ competition in the fuel retail market and its high margins.
Williams said: “We hope that greater transparency of fuel prices from the end of this year means that a spotlight is shone on both those forecourts that charge the fairest prices and indeed, those that sell petrol and diesel for far higher amounts.
“In the meantime, there are still some good deals to be had if drivers know where to look.
“The free myRAC mobile app – which is available to our members and non-members alike – pinpoints good-value forecourts and can help ensure drivers pay as little as possible every time they need to fill up.”
The RAC’s Fuel Finder tool found that the cheapest place to fill up with petrol as of 1st September was MFG Morrisons in Leighton Buzzard, where petrol was 126.7p per litre.
BP sites in Corby, Bovey Tracey and Liverpool followed, all selling petrol for 126.9p per litre.
The cheapest place to fill up with diesel was BP in Bovey Tracy, at 131.9p per litre, while MFG Morrisons stations in Blackpool and Widnes offered diesel at 134.7p per litre.
