BYD Seal U DM-i vs Kia Sportage PHEV: Price, Running Costs and Electric Range

On the BYD side, insurance groups are 32 for the Boost and Comfort trims and 40 for the all-wheel-drive Design, and company car tax on the 2026 to 2027 Benefit in Kind schedule works out at roughly £43 a month for a 20% taxpayer in the Comfort, rising to about £58 for the Boost and £66 for the Design. Carwow's long-term test of the Seal U DM-i averaged around 40 miles per gallon when charged regularly. An insurance group and a CO2 figure for the Sportage PHEV are not established from the sources this comparison uses, so no company car tax or insurance figure is given for it here; a buyer weighing the two on running costs should get both direct from a dealer or an insurer before ordering.

All figures here are the electric-only WLTP range, not a weighted combined mpg figure, and the two cars should never be read against each other on any other basis. The Seal U DM-i's Boost and Design trims cover 50 and 43 miles respectively on a smaller 18.3kWh battery, while the Comfort's larger 26.6kWh pack stretches that to 78 miles, among the longest electric-only ranges of any plug-in hybrid on sale in Britain. The Kia Sportage Plug-in Hybrid, on its own 13.8kWh pack, covers 44 miles electric-only WLTP on its Pure entry trim, a mile ahead of the Seal U's own Design trim though behind the Boost and Comfort. DC rapid charging tells a different story on the BYD side: 18kW maximum means a 30 to 80% top-up takes 35 to 55 minutes depending on battery size, offering little advantage over a 7kW home charger at a motorway services. Kia does not publish a DC charging figure for the Sportage PHEV at all; its own charging-time table lists this model only under AC columns.

Warranty is where the two split most clearly. The Seal U DM-i carries a 6-year or 93,750-mile vehicle warranty and an 8-year or 155,350-mile battery warranty with a 70% capacity floor, plus 12 years of bodywork cover. The Sportage PHEV carries Kia's standard 7-year or 100,000-mile warranty across the whole car, including the battery, with its own 70% capacity guarantee over that same period. So Kia's cover runs a year and 6,250 miles longer on the vehicle as a whole, while BYD's battery cover alone runs a year and 25,000 miles longer than Kia's. Both earn 5-star Euro NCAP ratings. Euro NCAP scored the Seal U DM-i at 90% for adult occupant protection, 86% child occupant, 83% vulnerable road users and 77% safety assist. The Sportage's own 5-star result dates to 2022, and Euro NCAP has not published a category breakdown for it, so this comparison states its star rating only rather than estimating one.

BYD announced on 15 January 2026 an 8-year / 250,000 km (about 155,350-mile) Blade Battery warranty for BEVs and Super Hybrids in Europe, including existing UK cars; ETP3 and some special fleet agreements are excluded. BYD's general UK policy page still lists 125,000 miles, so buyers should verify the VIN-specific warranty booklet or written dealer terms.