Charging an electric car at home is almost always cheaper than public charging — but how much cheaper depends heavily on your electricity tariff. Here is a complete breakdown for 2026.

The Basic Calculation

Cost to charge = battery size (kWh) × electricity unit rate (p/kWh) ÷ 100. A typical family EV has a 60-75kWh battery. On the current standard tariff cap rate of 24.5p/kWh: a 60kWh battery costs £14.70 for a full charge from empty. A 75kWh battery costs £18.38. In practice you rarely charge from completely empty — most EV owners top up from 20-30% daily, so real-world daily costs are typically £3-£8. If you want to compare energy deals, it only takes a few minutes.

Annual Charging Cost Comparison by Tariff

For a driver covering 8,000 miles/year in an efficient EV (approximately 3.5 miles/kWh, using ~2,285 kWh/year):

• Standard variable tariff at 24.5p: ~£560/year
• Octopus Intelligent Go at 7p overnight: ~£160/year (saving £400)
• Economy 7 at 10p overnight: ~£229/year (saving £331)
• Octopus Agile (average 15p): ~£343/year

The Right Charger Makes a Difference Too

A standard 3-pin plug charges at 2.3kW — fine for overnight top-ups but slow. A home wallbox charger (7kW) charges 3x faster and is safer for daily use. Installation costs £500-£1,200 but the government’s EV chargepoint grant covers 75% (up to £350) for homeowners. Factor this into your total cost of ownership calculation. You can also free heating and insulation grants to see what’s available.

Bottom Line

On the right tariff, home EV charging costs roughly a quarter of what you would spend on petrol for the same mileage. Switching to an EV-specific tariff like Intelligent Octopus Go is one of the most impactful energy decisions an EV owner can make. Compare energy tariffs for EV drivers today.