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EV calculator explained

How we calculate the cost savings in our calculator

Wondering what data our EV calculator is based on? Here's the lowdown.

What’s the pricing based on?

First up, all the pricing is a guide and is subject to change. All of the examples, both electric and petrol cars, are based on a four year, 5,000 mile agreement.

For the salary sacrifice example, we've based the pricing on a 40 year old living in Dorset - location and age affects the price of insurance.

What sort of lease are you comparing with?

We've made the comparisons as like-for-like as possible. By that we mean we've only selected petrol cars from leasing.com that don't have an admin fee when you order one. That's because there's no hidden fees with us. We've also added in just one month upfront for the petrol cars, as with salary sacrifice you don't pay anything in advance.

What are the fuel costs based on?

The fuel figures are based on the monthly cost of fuelling the car if you were to travel the full 5,000 miles in a year. For the EV, we've used the Intelligent Octopus Go off-peak rate of 7.5p/kWh, because charging your car at that time is best for your wallet and the planet. We've added on VAT, too.

The petrol cars use the same mileage, but the price is guided by the petrol pump price average for 2024 so far (we've taken the average price up to 27th March as our latest guide, but we'll update this monthly).

What’s the insurance cost based on?

Insurance takes the average price for the insurance group of the petrol car for a 40 year old to keep it in line with the person profile we used for salary sacrifice.

How did you calculate the maintenance cost?

Maintenance costs are based on Nimblefins' average annual maintenance cost, spread across 12 months.

Where are breakdown costs from?

Breakdown cover costs are taken from Which?'s AA report (AA is our EV salary sacrifice breakdown cover provider).

How’s the cost for tyres figured out?

Last up, tyres. Tyres typically last 20,000 miles before needing a replacement, so we think there might be one change across the agreement. Based on that, we've assumed you'd put decent tyres on your car, which Checkatrade say would cost £400 for a set. We've then spread that cost over 48 months to create a monthly figure.