Formula: (trip miles ÷ MPG) × fuel price per gallon. Class B: 18–24 MPG · Class C: 10–14 · Class A: 7–10.
How to use this calculator
Enter your planned driving distance, select your RV class, and plug in the fuel price at your pickup state (see our 2026 Fuel Cost Index below). The result is a directional fuel-only estimate — add campground fees, rental rate, and insurance for a full trip budget via our Trip Budget Estimator.
MPG benchmarks by RV class
| RV Class | MPG | 500 mi @ $3.65/gal | 1,000 mi @ $3.65/gal | 2,000 mi @ $3.65/gal |
|---|---|---|---|---|
| Class B | 18–24 | $76–$101 | $152–$203 | $304–$406 |
| Class C | 10–14 | $130–$183 | $261–$365 | $521–$730 |
| Class A | 7–10 | $183–$261 | $365–$521 | $730–$1,043 |
Diesel vs gasoline motorhomes
Most rental Class C and Class A motorhomes in the US run on gasoline. Diesel coaches (common in Europe and some US Class A fleets) get 15–25% better mileage but diesel often costs $0.40–$0.80/gal more at the pump. For a 1,000-mile trip, diesel savings only break even above ~14 MPG vs a comparable gas rig.
Sample fuel costs by popular route
| Route | Miles | Class C fuel @ $3.65 | City guide |
|---|---|---|---|
| Los Angeles → Joshua Tree | 140 | ~$43 | LA guide |
| Denver → Rocky Mountain NP loop | 320 | ~$97 | Denver guide |
| Phoenix → Grand Canyon (South Rim) | 230 | ~$70 | Phoenix guide |
| San Francisco → Yosemite | 195 | ~$59 | SF guide |
| Miami → Key West | 160 | ~$49 | Miami guide |
Fuel-saving tips for RV renters
- Drive 55–60 mph on highways — fuel economy drops sharply above 65 mph in large motorhomes.
- Pack light; every 500 lb of extra cargo can reduce MPG by 1–2% on Class C rigs.
- Use cruise control on flat interstate legs; avoid aggressive acceleration with a loaded coach.
- Plan fuel stops in lower-tax states on cross-country routes (e.g. fill up in Oklahoma vs California).
- Consider a Class B campervan for city-heavy itineraries where parking and MPG both matter.
Frequently asked questions
What MPG should I expect from a rental RV?
Fleet averages: Class B 18–24 MPG, Class C 10–14 MPG, Class A 7–10 MPG. Actual results vary with load, terrain, and driving style — mountain passes can cut MPG by 30% vs flat highway cruising.
Does the rental include fuel?
Almost never. You return the vehicle with the same fuel level as pickup (usually full-to-full). Budget fuel as a major line item — often $150–$600+ on a one-week road trip depending on distance and RV class.
How do I estimate fuel for a national parks loop?
Add daily driving miles (often 80–150/day on park circuits), multiply by trip days, then apply your class MPG. A 10-day Southwest loop from Phoenix (~1,400 miles) typically costs $425–$550 in fuel for a Class C at average US gas prices.
Compare live RV prices in your city → · 2026 Price Index → · RV class guide →