BYD Seal U DM-i running costs in the UK
How much does the BYD Seal U DM-i actually cost to run? Forget the 141 MPG brochure number — that figure assumes you start every trip with a full battery and only count the petrol miles. Here's what it really costs at UK 2026 prices, 10,000 miles a year, 60% of miles on battery.
BYD Seal U DM-i — at a glance
| Year | 2025 |
|---|---|
| Battery | 18.3 kWh |
| WLTP electric range | 50 miles |
| WLTP combined MPG | 141 mpg (brochure figure — see below) |
| Real-world petrol-only MPG | 45 mpg (once the battery's empty) |
The real annual cost
Total running cost / year
£770
7.7p/mile blended · 10,000 mi/yr · 60% on battery
Breakdown
| Battery miles (60%) | 2.3p/mile · £140/yr |
|---|---|
| Petrol miles (40%) | 15.7p/mile · £630/yr |
| Break-even fuel price | petrol would need to drop to £0.23/L for it to be cheaper than home off-peak charging |
vs a typical UK petrol car (40 mpg)
| 40 mpg petrol car | £1,772/yr (17.7p/mile) |
|---|---|
| BYD Seal U DM-i | £770/yr (7.7p/mile) |
| Annual saving | £1,002 (57% cheaper) |
The honest take. The BYD Seal U DM-i is 57% cheaper than a typical petrol car at these assumptions. The number that matters is your number — your old car's MPG, your tariff, your annual mileage, and how often you actually plug in. Plug your own figures into the free calculator below and you'll see in seconds.
📌 Save the BYD Seal U DM-i to your comparisons
Email yourself a one-tap sign-in link. Come back to this exact comparison any time, no password — your saving of £1,002/yr gets saved with it. Free.
The link goes to your saved comparisons. No spam, no password, no card. Delete your account any time.
🌍 Not in the UK? Prices are in £ (GBP). Once signed in, override the fuel and electricity prices in the calculator with your local rates — the maths works wherever fuel and electricity have prices.
Or: run your own numbers — free, no signup
Calculator opens pre-loaded with the BYD Seal U DM-i · adjust to your annual miles + tariff