Electric or petrol and diesel: which costs you less?

What the calculator computes

It compares the total cost of ownership of two cars over the chosen period: purchase minus residual value, energy, servicing and repairs, tyres, insurance, the annual motor vehicle tax and the one-off registration fee, plus the home charger for the EV. In a lease mode, the purchase is replaced by the down payment and the monthly payment.

Simple payback

Simple payback is the time it takes for the EV’s lower running costs to cover its higher up-front cost:

up-front difference = (EV price + charger + EV registration fee − grants) − (ICE price + ICE registration fee)

It is always computed the same way, whatever ownership period you selected: cumulative costs are compared over a fixed 25-year horizon and the crossing point of the two curves is found. Residual value is left out of the payback, because it is only realised when the car is sold. This rules out the situation where a 5-year selection shows no payback at all while a 10-year selection shows payback in the first year. In the lease modes payback is likewise computed on the full purchase price, so it does not depend on the purchase method, the monthly payment or the lease term. The marker on the chart shows where the two cumulative cost curves cross (including discounting, purchase method and residual value), so it can differ from simple payback.

Estonian motor vehicle tax

The annual tax follows the Motor Vehicle Tax Act: base 50 € + (CO₂ component + weight component) × age coefficient. The CO₂ component is tiered (up to 117 g/km 0 €/g; 118–150 → 3 €/g; 151–200 → 3.5 €/g; above 200 → 4 €/g). Weight component: for combustion and hybrid cars, gross weight above 2000 kg × 0.40 €/kg (capped at 400 €); for fully electric cars, above 2400 kg × 0.40 €/kg (capped at 440 €). Registration fee: base 150 € + CO₂ component (1–117 g/km 5 €/g; 118–150 → 10 €/g; 151–200 → 30 €/g; above 200 → 50 €/g) + weight component 2 €/kg above 2000 kg (2400 kg for an EV). The age coefficient applies to the CO₂ and weight components, not to the base. The annual-tax age coefficient is 0.92 from the fifth year and then steps down (year 6: 0.84; year 7: 0.75; year 10: 0.51; year 12: 0.35; years 15–19: 0.10); at 20 years and older the annual tax is only the 50 € base. The registration-fee age coefficient depends on the car’s age at registration: 0.87 (1 yr), 0.75 (2 yr), 0.65 (3 yr), 0.56 (4 yr), 0.48 (5 yr), 0.22 (10 yr), 0.10 (15 yr), 0.05 (20 yr and older).

For a van (N1) the annual tax is a 50 € base + a CO₂ component (205–250 g/km 3 €/g; 251–300 → 3.5 €/g; above 300 → 4 €/g), with no weight component; a fully electric van pays 30 €. The N1 registration fee is a 300 € base + a CO₂ component (1–204 g/km 2 €/g; 205–250 → 30 €/g; 251–300 → 35 €/g; above 300 → 40 €/g); a fully electric van pays 200 €. The age coefficients are the same as for cars. The binding amounts come from the Transport Administration (registration fee) and the Tax and Customs Board (annual tax).

Fuel consumption and WLTP CO₂

The motor vehicle tax and registration fee are calculated from the WLTP CO₂ value on the registration certificate (field V.7), while fuel cost and the CO₂ saving use real-world consumption. The two fields are deliberately independent: real-world consumption is usually higher than the laboratory (WLTP) figure, so changing consumption must not change the tax, and changing the tax figure must not change fuel cost. Choosing a vehicle class fills both with typical values; if you know your car’s actual consumption or the certificate figure, overwrite the relevant field. The CO₂ saving is calculated from real-world consumption and the carbon content of the fuel (petrol 2.31, diesel 2.64 kg/l), and from the CO₂ intensity of electricity.

Comparing your current car with a new EV

In the second mode the comparison is not between two new cars but between keeping your current car and buying a new EV. What you originally paid for your car is a sunk cost and does not matter — what matters is its market value, because that is money a sale would free up and it reduces the extra investment in the EV. Simple payback then shows how quickly lower running costs cover that gap.

No registration fee arises on the current car, since it is already registered. Its age is tracked separately: it raises servicing and repair costs, lowers the comprehensive premium along with the value, and lowers the motor vehicle tax through the age coefficient. The older car keeps depreciating, which shows up in its residual value at the end of the period.

At low mileage the result is often that keeping the current car is cheaper, because the depreciation of a new car exceeds the entire fuel saving. That is the correct answer, not a flaw in the model.

Servicing and repair costs

Maintenance has two parts. Scheduled servicing is triggered by mileage or by time, whichever comes first — by default 15,000 km or 12 months for a combustion car and 30,000 km or 24 months for an EV. Wear parts and repairs are mileage-based, grow 8% per year with age, and count at half rate while the car is under warranty, since the manufacturer covers defects but not wear items.

The defaults are calibrated against European and Estonian data. In January 2026 the ADAC collected 120 quotes from franchised dealers and found EV servicing to be 58% cheaper at BMW, 45% at Mercedes, 44% at Volkswagen and 39% at Hyundai than for a comparable combustion model — but at Dacia the combustion car was 43% cheaper, and almost half of the workshops charged roughly 17% more per hour for EV work. Consumer Reports' analysis of members' actual costs puts EV lifetime maintenance and repair at about half that of a combustion car, and shows how steeply cost rises with mileage: 1.2 cents per mile over the first 50,000 miles, more than 4 cents in the 100,000–200,000 mile range. For the Estonian price level, the average service invoice has been in the 300–400 € range and an independent workshop typically charges about half of dealer prices.

Two things follow. First, EV servicing is not automatically cheaper — for budget brands it can be more expensive, and workshops often charge a premium for high-voltage work. Second, repair costs are heavily right-skewed: a single major failure dominates the average, so the calculator shows a typical car, not yours. The realistic error here is around ±40%, which makes this the least certain part of the model.

Tyre costs

Tyres wear with kilometres, but the seasonal changeover and storage happen even when the car is barely driven, and rubber ages while standing still. The formula is therefore fixed part + set price × max(mileage / life, 1 / age limit). A low-mileage car reaches the age limit before the tread is gone, and from there age sets the pace.

The set price covers summer and winter tyres together and comes from the vehicle class, because the spread is wide: in Estonia a 15-inch tyre for a small car typically costs 50–70 €, while a 19-inch SUV tyre costs 110–150 €. An EV set is about 15% more expensive because it needs a higher load index and lower rolling resistance, and its life is shorter — 35,000 km by default against 45,000 km for a combustion car, since greater mass and instant torque wear the tread faster. All of these values are editable; between budget and premium tyres the market price differs by a factor of two.

Vehicle value and insurance

The comprehensive premium is based on the vehicle value, which starts at the purchase price and reaches your chosen residual value at the end of the period, following the shape of the depreciation curve in between. This also holds when buying used: the starting point is what you paid, not the original list price.

Discounting

The default discount rate is 3%: every figure shown is a present value — the totals, the cost breakdown, cost per kilometre and per month, the curves in the chart and the year-by-year table. For an outright purchase this charges the purchase price a cost of capital (what the money would earn as savings, or the interest on a loan); with a lease the interest is already in the monthly payments, so the purchase methods are comparable. With a discount rate of 0 the amounts are nominal and no cost of capital is charged on an outright purchase. Simple payback is deliberately left undiscounted, because it is meant to be a simple and comparable indicator.

Capital lease and operating lease

In both cases, the full-price purchase is replaced by your down payment (%) and a monthly payment. The default monthly payment is calculated with an annuity formula: the financed amount (price minus grant minus down payment) is paid back with the base rate (Euribor) plus margin, over the chosen ownership period. For a capital lease, the payment formula treats the residual value (buyout price) left at the end as a balloon payment — that's what makes the monthly payment lower — and that same buyout amount is added to the total cost as an actual cost line at the end of the period, which mostly offsets the residual-value credit below it (the difference is essentially the interest cost); the car is yours after the buyout. The buyout never exceeds the financed amount: if your down payment already covers part of the residual value, that part has been paid up front and is not charged again. For an operating lease, the payment formula also uses the residual value — you only pay the difference between price and residual value, plus interest — but there is no buyout and no residual-value credit at the end, because the car goes back to the leasing company. With the same assumptions, operating and capital lease therefore give the same total cost; they differ only if you enter the monthly payment of an actual quote by hand. This choice is separate from the "Include residual value" checkbox under "Advanced assumptions" — for the leased vehicle, that checkbox only affects a current car under the trade-in comparison, not the leased vehicle itself. You can always overwrite the monthly payment by hand if you have an actual lease quote — after that this payment is no longer updated automatically (the EV and the other car are tracked separately) until you press "Recalculate automatically" or change the purchase method. The car's price, consumption and weight stay the same basis for insurance as in the outright-purchase case. If servicing or insurance is already included in your lease payment, reduce those fields so the cost isn't counted twice. In the trade-in comparison (current car vs. new EV), the lease mode applies only to the new EV, since the current-car column shows its market value, not a purchase.

What the calculator leaves out

• Euribor changing during the lease term — the monthly payment is calculated with one fixed base rate for the whole period, even though a real lease usually resets it every 6 months.
• Fringe benefit tax on private use of a company car.
• The motor vehicle tax reduction for families with children (from 2026: 100 € per child).
• Parking discounts, road tolls, battery replacement after the warranty period, lease mileage-limit penalties.
• VAT on the sale of the car at its residual value.

Where the defaults come from

Prices and consumption by vehicle class are typical Estonian market figures for a new car and are meant to be overwritten. The default consumption of the petrol or diesel car is real-world, about 15% above the WLTP figure (the ICCT put the gap at 14% in 2022; the European Commission’s on-board data show about 20%); for the motor vehicle tax, WLTP CO₂ is a separate field. The default fuel price is 1.80 €/l, home charging 0.15 €/kWh and public charging 0.35 €/kWh. Default servicing: scheduled service 190 € for an EV (every 30,000 km or 24 months) and 300 € for a petrol or diesel car (every 15,000 km or 12 months), plus wear parts and repairs of 0.013 and 0.022 €/km. Before age and inflation growth, that comes to roughly 290 €/yr for the EV and 630 €/yr for the petrol or diesel car at 15,000 km/yr after the warranty period (during the warranty, the wear-and-repair part is halved).

The result is an indicative estimate, not tax or financial advice. The binding tax amount comes from the Estonian Tax and Customs Board.