2026 Rivian R1S All-Terrain Tri Max (20in): home charging cost in Mississippi

A 2026 Rivian R1S All-Terrain Tri Max (20in) draws 49.8 kWh per 100 miles per the EPA; at Mississippi's 15.35¢/kWh residential rate that's $7.65 per 100 miles charged at home, versus $16.02 for a 25.5-mpg gas car covering the same distance. Charging at home is much cheaper than gas here: 52.2% 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 Tri Max (20in) charged at home in Mississippi costs about $1,147/year in electricity, against about $2,403/year for the gas-car comparison. That's a savings of about $1,255 a year.

What one full charge costs

A 2026 Rivian R1S All-Terrain Tri Max (20in) needs roughly 164 kWh to reach its EPA-rated 329-mile range, which runs about $25.17 at 15.35¢/kWh in Mississippi.

2026 Rivian R1S All-Terrain Tri Max (20in) in Mississippi, ranked

This combination ranks 14,496 of 20,400 state/model pairs for cost savings against gas (1 is cheapest). The Rivian R1S All-Terrain Tri Max (20in) alone ranks 388 of 400 models for efficiency; Mississippi alone ranks 22 of 51 states for electricity price.

Next step: home charger installation

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 Mississippi electrician to quote the install before this math becomes a real decision.

Where these figures come from

The methodology guide names the exact EIA and EPA tables behind this page's numbers. At 15.35¢/kWh, Mississippi sits in the middle of the national range — the guide to why charging cost varies by state shows where.