Charging a 2027 Rivian R1S Performance (20in AT) at home in Montana

A 2027 Rivian R1S Performance (20in AT) draws 49.8 kWh per 100 miles per the EPA; at Montana's 13.77¢/kWh residential rate that's $6.86 per 100 miles charged at home, versus $16.02 for a 25.5-mpg gas car covering the same distance. That works out to 57.2% cheaper per mile than gasoline in Montana — charging at home is much cheaper than gas here.

2027 Rivian R1S Performance (20in AT): yearly cost in Montana

Montana owners putting 15,000 annual miles on a 2027 Rivian R1S Performance (20in AT) spend about $1,029 on home electricity, compared to about $2,403 a gas-car equivalent would spend on fuel. Call it about $1,374 saved annually, at this mileage.

What one full charge costs

At Montana's rate, fully covering this 2027 Rivian R1S Performance (20in AT)'s 329-mile EPA range costs about $22.58 (164 kWh) — the energy the EPA test actually used, not the battery's rated size.

How this compares nationally

Among all 20,400 state-and-model combinations this site tracks, charging a 2027 Rivian R1S Performance (20in AT) in Montana ranks 12,673 for cost savings versus gas — 1 being the best deal nationally. Separately, the Rivian R1S Performance (20in AT) ranks 386 of 400 EV models for raw efficiency, and Montana ranks 10 of 51 for cheapest residential electricity.

Next step: home charger installation

Everything above is the per-mile and per-year cost once a home charger exists — getting one installed is a separate electrical job whose price depends on your panel and wiring, not the state average used here.

Line up a few Montana electrician quotes for Level 2 install before you commit either way.

More on how this number was built

See the methodology guide for exactly which EIA and EPA figures feed 2027 Rivian R1S Performance (20in AT)'s cost in Montana. Montana's 13.77¢/kWh rate ranks 10 of 51 states; the state rate guide lays out the full spread.