Average Cost Of RV Gas Per Trip: Is Calculating Gas For Your RV Hard?

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If you’re planning an RV road trip, the first thing on your mind is the cost of filling up the tank. Knowing this information can help you plan your budget and save you from over budget. So, how much does filling up an RV gas tank cost?

The exact cost to fill up your RV’s gas tank will depend on the size and make of your vehicle and current fuel prices. Generally speaking, expect it to cost you somewhere between $50 and $300 depending on the size of your gas tank. For example, a 50-gallon tank may require up to $300 to fill up, while a 10-gallon tank would cost much less.

rv gas cost calculator

Larger RVs with bigger tanks are likely to cost you higher, while smaller Class B or Class C RVs will likely cost you less. Filling up an RV gas tank isn’t quite like filling up a regular car—the size and capacity of an RV’s fuel tank present different challenges and numbers when determining how much you’ll need to pay each time. 

In this post, we’ll cover all the details so you know what to expect when refueling during your adventure with an RV! Ready? Let’s dive in!

Gas Calculator for RV

To use the RV gas calculator, simply input the following information:

  • Miles Per Gallon (mpg): This is the average fuel efficiency of your RV, expressed in miles traveled per gallon of fuel. You can find this information in the owner’s manual or from the manufacturer.
  • Cost of Gas: This is the current price of gasoline, expressed in dollars per gallon. You can find this information at a local gas station or online.
  • Distance in Miles: This is the total distance you plan to travel in your RV, expressed in miles. You can use a route planning tool or app to help you estimate the distance between your starting point and destination.

Once you have entered this information, the calculator will estimate the total fuel cost for your trip. 

Total Gas Cost: $

What Are the Sizes of RV Gas Tanks?

An RV gas tank’s size depends on its type, model, and purpose. The most common types are Class A, B, and C RVs. Each class has different size tanks best suited to the recreational vehicle’s needs and capacity. Here is a detailed breakdown of the gas tanks of different RVs.

Class A RV Gas Tank Size

Class A recreational vehicles are designed for long-distance travel and offer the most luxurious accommodations. These RVs are large and require a considerable amount of fuel to operate. The lightest Class A RVs have a fuel tank capacity of 80 gallons, while the largest ones are nearly double that, at 150 gallons. Keeping this range in mind, the average Class A motorhome will travel 8 to 13 miles per gallon of gasoline.

Class B RV Gas Tank Size

Class B recreational vehicles are smaller and made for shorter trips. These RVs offer a more compact design with features that make them easy to drive. Class B RVs usually have fuel tank capacities between 25 gallons, so the driver doesn’t need to fill the tank as often. 

Class C RV Gas Tank Size

Class C RVs are larger than Class B and offer more amenities but don’t require as much energy as a Class A motorhome. Class C RVs have fuel tank capacities between 25 and 100 gallons and can get up to 8 miles per gallon of gasoline.

Factors Determining The Size Of RV Fuel Tank

Various factors can affect the size of an RV fuel tank, including vehicle type, intended usage, and fuel efficiency. Knowing these factors can help determine how much fuel capacity is needed for a particular trip or adventure.

Vehicle Type

One of the key factors in determining fuel tank size is the type of vehicle being driven. Generally, larger vehicles require more fuel than smaller ones to cover longer distances and heavier loads. Motorhomes usually have bigger tanks than other recreational vehicles (RV) types, such as travel trailers or pop-up campers.

Intended Usage

The intended usage of the vehicle will also play a role in determining the size of an RV’s fuel tank. If long-distance travel is expected, then a larger tank may be necessary to ensure enough fuel can be stored for the entire duration of the trip. Conversely, a smaller fuel tank might suffice if short trips are planned.

Fuel Efficiency

Finally, the fuel efficiency of a vehicle’s engine is another factor that should be taken into consideration when determining an RV’s required fuel capacity. A vehicle with better fuel efficiency will require less fuel to cover the same distance as one with lower efficiency. As such, fuel tanks with smaller capacities can be used to cover the same distances.

It is important to remember that different RV gas tanks can have unique fuel efficiency ratings. For example, aluminum tanks are generally more efficient at holding and releasing fuel than fiberglass or plastic tanks. With the right maintenance, an RV owner can increase their vehicle’s fuel efficiency by ensuring that their tank is clean and free of debris.

What Are The RV Mileage By Class?

It is difficult to provide specific gas mileage figures for Class A, B, and C RVs, as many variables can affect fuel efficiency, including the size and weight of the RV, the type of engine it has, and the way it is driven.

Additionally, fuel efficiency can vary widely even among RVs of the same class and type, as different models and manufacturers may have different designs and features that affect fuel consumption. RV classes refer to the type of vehicle and the amenities it offers. 

Here are the details of each class:

Class A

Class A RVs are the largest and most luxurious type of motorhome. They are built on a bus chassis and range in length from about 25 to 45 feet. Class A RVs typically have a range of high-end features, including multiple slide-outs (sections of the RV that can be extended outward to create more interior space), full kitchens, multiple bedrooms and bathrooms, and plenty of storage. They are designed for extended travel and have all the comforts of home.

Class B

Class B RVs, also known as camper vans, are smaller and more compact than Class A RVs. They are built on a van chassis and range in length from about 17 to 23 feet. Class B RVs are built for maneuverability and can easily be driven and parked in most places. They have a small kitchen and sleeping area and may have a bathroom with a shower. These RVs are best for solo travelers or couples who want a more compact and efficient option for traveling.

Class C

Class C RVs are intermediate in size and are built on a truck chassis. They range in length from about 22 to 40 feet. Class C RVs typically have a sleeping area over the cab and may have a bunk over the back of the RV. They have a kitchen, bathroom, and dining/sitting area. Class C RVs are a good choice for families who want more space than a Class B RV offers but still want an easy vehicle to drive and maneuver.

To get a rough estimate of the fuel efficiency of a particular RV model, you can consult the manufacturer’s specifications or ask the dealer or owner directly. Some RVs may also have a sticker on the vehicle that provides fuel economy information. Still, here is a rough estimate of average mileage varying with RV types:

RV ClassesClass AClass BClass C
Average Mileage 7 to 13 mpg18 to 25 mpg14 to 18 mpg

How Much Fuel Does It Cost To Fill an RV Gas Tank? 

The cost to fill an RV gas tank will depend on the tank’s size, the gasoline price, and the distance you plan to travel. RVs typically have larger fuel tanks than passenger cars to hold more gasoline. However, the cost of filling an RV gas tank can still be significant, especially if you are planning a long road trip.

To get a rough estimate of the cost to fill an RV gas tank, you can use a fuel cost calculator or try the following method:

  • Find the size of your RV’s fuel tank in gallons. This information should be available in the owner’s manual or from the manufacturer.
  • Check the current price of gasoline in your area. You can find this information online or at a local gas station.
  • Multiply the size of your fuel tank in gallons by the current price of gasoline. For example, if your RV has a 75-gallon fuel tank and gasoline sells for $3.00 per gallon, it would cost approximately $225.00 to fill the tank.

Remember that this is just a rough estimate. The actual cost may be higher or lower depending on various factors.

What Is The Average Distance Traveled During RV Trips?

According to the statistics, most RV trips in 2021 were relatively short, with 31% of people traveling less than 50 miles and 25% traveling 51 to 100 miles. Only 16% of people traveled more than 500 miles in their RVs.

This suggests that the average distance traveled during RV trips in 2021 was relatively short, with most people staying relatively close to home. The COVID-19 pandemic and related travel restrictions may have influenced these patterns, as people may have been more hesitant to travel long distances or to stay in crowded areas.

It is important to note that these statistics represent only a snapshot of RV travel in 2021 and may not represent travel patterns in other years or for all RVers. The distance traveled during an RV trip can vary widely depending on the individual or group traveling, the length of the trip, and the destination.

Moreover, some people may take short weekend trips in their RV. In contrast, others may take extended vacations or even full-time RVing, traveling long distances and staying on the road for extended periods.

In general, it is difficult to determine the average distance traveled by all RVers, as there is a wide range of travel patterns and destinations among RV owners. Some popular destinations for RVers include national parks, beaches, and other outdoor recreation areas, as well as major cities and tourist attractions.

Check Out Ideal Travel Distance for an RV Day – How Far We Drive – Full Time RV:

Motorhome Diesel vs Gas

Motorhomes are a great way to explore the outdoors and enjoy camping in comfort. However, when it comes to choosing between diesel or gas for your motorhome, there are some important considerations. Here is an overview of both types of fuel and how they compare.

Fuel Efficiency 

Diesel RV tend to be more fuel efficient than their gasoline-powered counterparts. This is because diesel engines are generally more efficient at converting fuel into energy so that they can go further on a single fuel tank. This can be especially beneficial for long road trips or for those who plan to do a lot of driving in their motorhome.


In terms of performance, diesel engines tend to have more torque and better low-end power, which can help tow and haul heavy loads. Gasoline engines, on the other hand, gasoline engines may have better acceleration and higher top speeds. So, a diesel engine might be the way to go if you’re looking for a motorhome that can easily haul a lot of gear or tow a trailer.


One potential downside to diesel motorhomes is that diesel fuel is usually more expensive than gasoline. This means that operating a diesel motorhome may be more expensive in terms of fuel costs. However, diesel engines are known for being durable and requiring less maintenance, so lower maintenance expenses over the long term may offset the higher fuel costs.

Comfort And Luxury

Diesel-powered motorhomes typically offer more power than their gas counterparts to provide a smoother ride with less vibration. They are also quieter when running. On the other hand, gas-powered motorhomes are less expensive. They may offer more features like air conditioning, home-like furnishings, and improved suspension systems.

Speed And Towing Ability

Diesel motorhomes are typically capable of towing larger loads and providing greater acceleration than gas motorhomes. The increased torque of the diesel engine also makes it easier to tow heavy items such as boats or trailers. Diesel engines are also more efficient at higher speeds, allowing you to travel longer distances with less fuel consumption.


Diesel engines require more frequent maintenance than gas engines. They also require specialized parts, which can be more expensive. However, diesel engines are typically more durable and require fewer repairs than gas engines so that this cost may be offset over time.

Environmental Impact

Diesel fuel produces lower emissions than gasoline, making it a more environmentally-friendly choice. However, diesel engines also require special filters and treatments to reduce exhaust pollution


Diesel fuel is not as widely available as gasoline, so it may be more difficult to find diesel fuel when traveling in some areas. This could be a concern for those who plan to do a lot of driving or who may be traveling to remote locations.

Which One Is Better?

Overall, whether a diesel or gasoline motorhome is, the better choice will depend on your specific needs and preferences.

Key Takeaway: Consider factors such as fuel efficiency, performance, cost, and availability when making your decision.

Check Out RV Fuel Saving Tips & Hacks – Hypermiling Secrets — 25% or Better MPG:

Tips On How To Save On RV Gas

Here are some expert tips on saving on RV gas:

  1. Plan your route carefully: Map out your route in advance and take the most direct and efficient route possible. Avoid congested areas and try to avoid driving during peak traffic times. Consider using a GPS device or a routing app to help you find the most efficient route.
  2. Maintain a steady speed: Maintaining a steady speed can help improve fuel efficiency. Avoid rapid acceleration and braking, and try to maintain a consistent speed as much as possible.
  3. Use cruise control: If your RV is equipped with cruise control, use it to maintain a steady speed and save on fuel.
  4. Avoid excessive idling: Idling your RV for extended periods of time can be a major drain on fuel. If you need to stop for a short period, it’s usually more fuel-efficient to turn the engine off and then start it again when you’re ready to go.
  5. Lighten your load: The more weight your RV is carrying, the more fuel it will use. Try to travel with only the essentials and leave any unnecessary items behind to help save money on fuel.
  6. Consider using a fuel-saving device: A variety of fuel-saving devices on the market claim to improve fuel efficiency. While some of these may be effective, it’s important to research and be skeptical of any product that seems too good to be true.
  7. Use fuel-efficient tires: Properly inflated tires can improve fuel efficiency, as can using low-rolling resistance tires.
  8. Use the right fuel grade: Make sure to use the grade of fuel recommended by the manufacturer for your RV. Using a lower grade of fuel than recommended can reduce fuel efficiency.
  9. Use a fuel-efficient driving style: Avoid aggressive driving and anticipate stops and turns in advance to avoid sudden braking and acceleration.
  10. Keep your RV well-maintained: Regular maintenance can help your RV run more efficiently and use less fuel. This includes keeping the tires properly inflated, using the correct type of oil, and replacing the air filter as needed.
  11. Consider using a fuel rewards program: Many gas stations offer rewards programs that allow you to earn discounts or cash back on fuel purchases. Enrolling in a program like this can help save you money on RV gas.
  12. Consider alternative fuel options: If your RV is equipped with a flexible fuel engine, consider using alternative fuels like propane or natural gas price to save on fuel costs.

Related Questions

How often do you have to fill up an RV?

Depending on the size and type of your RV, you might fill up more or less frequently. For example, a larger motorhome with a 40-gallon tank will require more frequent refills than a smaller trailer with a 15-gallon tank. 

Although the exact amount of time between fill-ups will depend on your RV’s size, features, and usage, it is generally recommended that you should expect to fill up on water every 2 to 3 days. If you are planning a longer road trip in an RV, you should plan out your stops accordingly to ensure that you always have access to a freshwater supply. 

What is the average gas tank size?

The average gas tank size for vehicles falls between 25-100 gallons. This range can vary depending on the vehicle’s engine size, fuel economy, and make and model. SUVs, trucks, minivans, and other large vehicles tend to have larger fuel tanks than sedans or compact cars.

Generally speaking, smaller cars will require fewer gallons of fuel to fill their tank, while larger vehicles will require more. In addition, some cars are designed with an auxiliary gas tank which may increase the overall fuel capacity.

What is the biggest RV gas tank size?

The biggest RV gas tank size available is 150 gallons, making it an ideal choice for those who need to go the distance on their long journeys. It’s also important to note that this capacity is only available for certain types of recreational vehicles, so check with your dealer before purchasing one.

How many gallons of gas does a large RV hold?

A large RV can typically hold between 80 and 150 gallons of gasoline. This amount may vary depending on the RV’s size, model, or make, but it is good to always fill your tank with no more than this amount. Keeping a full tank helps ensure that you have enough fuel for your journey and that you will not run out while on the road.

Additionally, it is important to check your tank levels regularly to not overfill the tank and cause any spills or accidents. If you are planning a long trip, always make sure to fill up with enough gas for the journey ahead of time.

The Bottom Line

The cost of filling up an RV gas tank can vary greatly depending on the size of your tank and how long you’ve been traveling. For this reason, it’s important to budget for fuel costs ahead of time before setting out on your trip. 

Just make sure you consider how long your travels will take and where you will be going, so you can estimate how much fuel you should bring with your RV. Ultimately, the best advice is to enjoy the journey without stressing over the cost – as long as you plan carefully beforehand, you’ll be good to go!

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Written by William Perry
William was born and raised in the United States and currently lives in Utah. A retired police officer, he is the father of three and grandfather of six. Along with writing, he enjoys traveling, the outdoors, reading and spending time with his grandchildren.
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