Filling the tank of a 47-litre family hatchback with petrol now costs about £85, or £88 for diesel.
Despite recent energy price increases, charging at home to deliver the equivalent mileage typically costs less than half of that - about £41.
But drivers typically do a mix of 70% charging at home and 30% at public chargers, according to the Energy Saving Trust.
Public charging costs vary but this hybrid approach could cost about £48, still significantly cheaper than conventional fuel.
The price difference between electric cars and traditional vehicles is narrowing, and is expected to largely disappear.
But for now, a typical new electric car remains more expensive than an equivalent petrol or diesel model - ranging from £23,000 to £43,000.
