Asda Plymouth Supercentre: 169.7p a litre, 4.1 miles away. 2.2p a litre cheaper: saves £1.21 a tank, and costs about £1.58 of fuel to get there and back. Not worth the trip.
Mfg Morrisons Plymstock: 169.9p a litre, 1.5 miles away. 2.0p a litre cheaper: saves £1.10 a tank, and costs about 57p of fuel to get there and back. Worth the trip.
Mfg Plymouth: 169.9p a litre, 2.5 miles away. 2.0p a litre cheaper: saves £1.10 a tank, and costs about 96p of fuel to get there and back. Worth the trip.
Mfg Plympton: 169.9p a litre, 2.9 miles away. 2.0p a litre cheaper: saves £1.10 a tank, and costs about £1.11 of fuel to get there and back. Not worth the trip.
Mfg Landmark: 169.9p a litre, 3.8 miles away. 2.0p a litre cheaper: saves £1.10 a tank, and costs about £1.46 of fuel to get there and back. Not worth the trip.
On a 55-litre tank at 40mpg. The distance is straight-line rather than by road, so a real trip is longer than the one costed here.