2026 Rivian R1S All-Terrain Performance Dual Max (20in): home charging cost in Idaho

At Idaho's residential electricity rate of 12.8¢/kWh, a 2026 Rivian R1S All-Terrain Performance Dual Max (20in) (rated 43.2 kWh per 100 miles by the EPA) costs $5.53 to drive 100 miles on home charging, against $16.02 for the same distance in a car averaging 25.5 mpg on gasoline at $4.085/gallon. Charging at home costs a fraction of what gas would here: 65.5% less than gas per mile, here specifically.

What a year of driving costs

Driving 15,000 miles a year — fueleconomy.gov's own default assumption — a 2026 Rivian R1S All-Terrain Performance Dual Max (20in) charged at home in Idaho costs about $830/year in electricity, against about $2,403/year for the gas-car comparison. That's a savings of about $1,573 a year.

What one full charge costs

A 2026 Rivian R1S All-Terrain Performance Dual Max (20in) needs roughly 159.9 kWh to reach its EPA-rated 370-mile range, which runs about $20.47 at 12.8¢/kWh in Idaho.

How this compares nationally

This combination ranks 7,106 of 20,400 state/model pairs for cost savings against gas (1 is cheapest). The Rivian R1S All-Terrain Performance Dual Max (20in) alone ranks 334 of 400 models for efficiency; Idaho alone ranks 3 of 51 states for electricity price.

Before you install a home charger in Idaho

The numbers above assume Level 2 home charging is already in place — the electrical work behind that is a real, separate cost that varies by panel, wiring, and local labor rates, not something this page's per-mile math includes.

Ask a licensed Idaho electrician to quote the install before this math becomes a real decision.

Where these figures come from

See the methodology guide for exactly which EIA and EPA figures feed 2026 Rivian R1S All-Terrain Performance Dual Max (20in)'s cost in Idaho. Idaho is one of the cheapest states for home electricity — the guide to why the cost varies so much by state covers what drives that.