Asda, Morrisons, Sainsbury's and Tesco will all cut up to 2p per litre off both petrol and diesel prices tomorrow.
It's the second time the supermarket giants have dropped fuel prices in less than a month, after costs fell by up to 3p per litre on 12 June (see the Petrol prices MSE News story).
But the cuts don't necessarily mean these retailers will be cheapest. You can use the PetrolPrices.com website to find the lowest cost in your area.
Asda says it's cutting prices at the pumps because of falling oil prices, and adds its customers will pay no more than 127.7p per litre of unleaded and 132.7p per litre for diesel.
Morrisons, Sainsbury's and Tesco prices vary locally.
The average price of unleaded petrol recorded yesterday was 131.98p per litre, while diesel was 137.32p per litre, according to PetrolPrices.com.