Charging an electric car at home: cost and cheapest time
An electric car is a home’s largest flexible load. The calculator shows the cost of a charge at the cheapest and dearest start today or tomorrow.
Checked by Radif Partners · Editorial policy · Method and sources
A three-phase 16 A home charger charges at 11 kW, so a 40 kWh charge takes about 3.6 hours. In Helsinki, on Helen Sähköverkko’s general transfer and a spot contract with a 0.51 c/kWh margin, such a charge costs €3.81 today at the cheapest start (04:30) and €5.15 at the dearest (14:45). At the day’s average price it costs €4.53. On Kymenlaakson Sähköverkko’s night transfer, where the night transfer fee is under a cent, the cheapest charge costs €2.38. Charged at the cheapest time, 100 kWh costs €9.53 in Helsinki today, so with your car’s consumption you can work out the cost per kilometre. On general transfer, transfer and tax are the same every hour, but spot price swings make timing worthwhile. Enter the energy to charge, charging power, operator and contract below to see the cheapest start.
Electric car: cheapest run today
€3.81
40.00 kWh over 3.64 h
| Cheapest start 04:30 | €3.81 |
| Dearest start 14:45 | €5.15 |
| At the day’s average price | €4.53 |
| Per year, 2 times a week at average price | €471 |
Exchange prices published for 17 October 2026, FI bidding zone, source Nord Pool.
Assumptions
Energy is spread evenly over the quarters of the run. Price = spot + margin (or fixed price) + transfer fee + electricity tax, all incl. 25.5% VAT. Real use varies with the appliance, programme and temperature. Method and sources
Today’s charging cost
| Network and product | Cheapest start | At average price | Dearest start |
|---|---|---|---|
| Helen, general transfer | €3.81 (04:30) | €4.53 | €5.15 (14:45) |
| Kymenlaakson Sähköverkko, night transfer | €2.38 (03:15) | €3.50 | €4.39 (14:45) |
Charging losses are not included: some electricity turns into heat in the charger and battery, so a little more is drawn from the grid than reaches the battery. Enter the energy drawn from the grid if your charger or car app shows it.
Flexibility is the electric car’s advantage
Motiva encourages moving flexible use to cheap hours. An electric car is ideal for this, since it often sits at home all night and the charge is short compared with the time parked. Most cars and chargers have a timer or spot-price-based control that can start charging automatically in the cheapest window once tomorrow’s prices are out.
Cost per kilometre
If you know your car’s consumption in kilowatt-hours per 100 km, multiply it by the price of 100 kWh and divide by 100. Today 100 kWh charged at the cheapest time in Helsinki costs €9.53. In winter consumption rises because of heating, and spot prices are often higher. See tomorrow’s cheapest time on the tomorrow page and typical cheap hours in the cheapest time guide.