In the UK the answer is, typically ‘less than in a petrol or diesel car’ as fuel costs for a petrol or diesel car are usually in the range 10-15p/mile, and only 6p/mile for a home-charged pure-EV. Because of the variety of models available, each will have different costs per trip, depending on where it is charged, and how efficient the EV is compared to other electric models.
For further information we recommend reading : Cost of charging on a public network in the UK.