The EPA rates the 2026 Rivian R1S Dual Motor, Max pack at 410 miles combined and 39.9 kWh per 100 miles measured at the wall, which is 84 MPGe. Only 2 cars here go further on a charge. City and highway split 441 and 373 miles, a 15 per cent drop on the highway.
The Max pack holds 142.3 kWh usable out of 149.0 kWh gross — a 6.7 kWh reserve, about 4.5 per cent, which is a conventional buffer rather than the deep one Ford uses on the Lightning. Cells are NMC on a 400-volt bus. Put the usable figure against the EPA range and the car draws 34.7 kWh per 100 miles from the battery against 39.9 kWh at the wall: roughly 13 per cent of what you pay for never reaches the pack. That gap is charging loss, and it is the reason the per-state running costs on this site are built on the wall figure and not the battery figure.
On DC it accepts 210 kW at peak and completes 10 to 80 per cent in 48 minutes. Forty-eight minutes sounds slow next to an 800-volt car, and it is, but the arithmetic is kinder than the headline: 70 per cent of 142.3 kWh is 99.6 kWh, so the R1S is averaging about 125 kW across the whole session — it holds a high rate for longer than cars that peak higher and then taper. In range terms that is roughly 287 miles added in 48 minutes, close to six miles a minute. At home the 11.5 kW onboard charger is the limit.