2026 Rivian R1S All-Terrain Tri Max (20in) MPG & Specs — Real Fuel Cost
Quick answer
The 2026 Rivian R1S All-Terrain Tri Max (20in) gets an EPA-estimated 72/63 MPG (city/highway) and 68 MPG combined, with an estimated $1,100/year fuel cost.
The 2026 Rivian R1S All-Terrain Tri Max (20in) with the listed electricity engine returns an EPA-estimated 72 MPG in the city and 63 MPG on the highway, for a combined 68 MPG. This page summarizes the official EPA fuel-economy and emissions data for this configuration.
| Engine | — |
| Transmission | Automatic (A1) |
| Drive | 4-Wheel Drive |
| Fuel type | Electricity |
| Vehicle class | Standard Sport Utility Vehicle 4WD |
| MPG — city | 72 |
| MPG — highway | 63 |
| MPG — combined | 68 |
| Annual fuel cost* | $1,100 |
| CO₂ tailpipe | — |
| EPA GHG score | 10/10 |
| Electric range | 329 mi |
How efficient is it?
As an all-electric vehicle, the 2026 Rivian R1S All-Terrain Tri Max (20in) is rated in MPGe rather than MPG, and running costs are dominated by electricity rather than fuel. That is about 126% better than the typical Standard Sport Utility Vehicle 4WD of its era (30 MPG class average), making it one of the more efficient choices in its class.
Fuel economy and running costs
At about $1,100 per year in fuel (EPA estimate, 15,000 mi/yr), fuel is a major part of the cost of owning the 2026 Rivian R1S All-Terrain Tri Max (20in). Over five years that is roughly $5,500 at today's prices — before insurance, maintenance, and depreciation.
How to read these numbers
EPA figures come from standardized laboratory test cycles and are the same estimates shown on the vehicle's window sticker. Your real-world mileage depends on driving style, conditions, fuel grade, and maintenance. Use combined MPG and annual fuel cost to compare vehicles fairly.