A map can give you kilometres, but it cannot know how much fuel your particular tow vehicle and caravan will use into a headwind, over a range or after a detour. A useful fuel budget starts with your own towing consumption and leaves room for the trip you will actually drive.
The practical formula is: trip kilometres ÷ 100 × towing litres per 100 km × dollars per litre. Add realistic extra distance and a budget margin rather than treating the result as a guaranteed price. The free Trip Fuel Cost Calculator organises those inputs into a planning estimate.
Why caravan towing fuel cost differs from solo driving
A caravan adds mass, rolling resistance and a large aerodynamic load. The effect varies with its height and width, the gap behind the tow vehicle, speed, wind, gradients, road surface and how often the combination accelerates. Two caravans of similar mass can produce different consumption.
Your dashboard’s solo average is therefore a weak starting point. Use records from representative towing days when possible. If you are new to the combination, begin conservatively and update the estimate after the first few fills.
Figures to collect before calculating
- Base route distance: the door-to-door route, not a straight-line figure.
- Expected towing consumption: litres per 100 km from fills or a cautious planning estimate.
- Fuel price: a current observed price for the fuel grade your vehicle requires.
- Extra-distance allowance: side trips, town access, missed turns, camp detours and fuel-station diversions.
- Budget margin: room for price changes and conditions that increase consumption.
- Usable tank range: based on a reserve you choose, not on running the tank dry.
Record where and when each figure came from. A current price from a regional fuel service and a consumption average from your own log are more useful than an old national average.
Measure towing consumption from fill to fill
Fill the vehicle consistently, reset the trip meter and record litres added at the next fill. Divide litres by kilometres and multiply by 100. For example, 68 litres over 340 km gives 68 ÷ 340 × 100 = 20 L/100 km.
One fill can be distorted by pump cut-off, slope, short distance or unusual conditions. Keep several entries and note wind, terrain, speed, traffic and whether the caravan was attached. A range—perhaps an ordinary-day figure and an adverse-day figure—is more honest than one perfect-looking average.
Build distance from the real itinerary
Start with the main route, then count driving that map summaries often hide: reaching a caravan park outside town, collecting supplies, returning to an attraction, finding a suitable fuel outlet and repositioning after a closure. If the tow vehicle will be used without the caravan at camp, calculate that side-trip fuel separately using a solo consumption figure.
A percentage allowance is convenient, but kilometres are easier to defend. List known extras first, then add a modest unknown-distance allowance. Do not enlarge the number merely to make the budget look cautious; explain what it covers.
Use a current fuel price without pretending it will hold
The ACCC explains that regional fuel prices are generally higher than capital-city prices because of factors including lower demand, fewer outlets and higher storage and transport costs. Regional prices also tend to move more slowly. Use a price that reflects the route rather than your home suburb.
Government and other fuel-price services can help check likely stops. Availability and freshness vary, and a listed price does not guarantee a suitable bowser is open or stocked. Recheck close to departure and carry only fuel containers permitted and suitable for your setup.
Factors that change towing fuel use
- Speed: aerodynamic demand rises strongly as speed increases. Drive legally and to conditions; do not set a target solely to chase a calculation.
- Wind: a headwind or crosswind can raise consumption and fatigue.
- Terrain: climbing, repeated braking and acceleration, corrugations and soft surfaces all matter.
- Tyres and maintenance: use manufacturer-specified pressures for the real load and keep the vehicle and caravan maintained.
- Mass and shape: water, accessories and roof-mounted equipment affect the job the vehicle must do.
- Traffic and stops: towns, roadworks and queues can reduce the usefulness of a steady-speed figure.
Worked Australian trip example
A fictional itinerary has a 1,420 km mapped route. The travellers add 110 km for supplies, a caravan-park detour and a likely route variation, giving 1,530 km. Their logged towing average is 19.5 L/100 km. They use an example planning price of $2.15 per litre; this is not a current quoted price.
- Fuel volume: 1,530 ÷ 100 × 19.5 = 298.35 litres.
- Estimated fuel cost: 298.35 × $2.15 = $641.45.
- A 12% budget margin: $641.45 × 0.12 = $76.97.
- Planning budget: approximately $718.43.
The margin is a budgeting choice, not a prediction. If the route includes remote stretches, the travellers also identify fuel stops, opening information and the distance between reliable supplies.
Range planning is separate from cost planning
A trip may fit the overall budget but contain one leg that exceeds comfortable range. Estimate usable range from the fuel you are willing to consume before refuelling. A 130-litre tank with a chosen 25-litre reserve leaves 105 litres for planned use. At 20 L/100 km, that represents about 525 km under the assumed conditions.
Do not plan to arrive on fumes. Detours, closed outlets, wind and inaccurate gauges can consume the apparent margin. For remote travel, confirm current road and fuel conditions with authoritative local sources and appropriate operators.
Compare ordinary and adverse scenarios
A single answer can hide the conditions that matter most. Run an ordinary scenario using the middle of your logged towing range, then an adverse scenario using the higher consumption you have seen in wind, hills or slower surfaces. Use a current route price in each case.
Suppose the 1,530 km example is also tested at 22 L/100 km and $2.35 per litre. The estimate becomes 1,530 ÷ 100 × 22 × $2.35 = $791.01 before any budget margin. The gap from the ordinary example is almost $150. That does not mean the adverse scenario will occur; it shows whether the trip budget can absorb it.
Keep assumptions visible. If conditions improve, the unused amount remains a buffer rather than money that must be spent.
Use the log after the trip
Record each towing leg, litres, price and relevant conditions. Compare planned and actual distance separately from planned and actual consumption. This shows whether the main error came from itinerary changes or the vehicle–caravan estimate.
After several trips, create three figures: calm highway, mixed touring and adverse conditions. Do not combine solo sightseeing fills with towing data unless the kilometres are separated. A simple note beside each fill makes the next calculation much more useful.
Fuel economy should not drive unsafe choices
A lower consumption figure is never a reason to use the wrong tyre pressure, coast unsafely, obstruct traffic, exceed a component limit or avoid a necessary rest or fuel stop. Drive to road, traffic and weather conditions and follow manufacturer instructions.
If consumption changes sharply, consider wind, terrain and measurement error, but also look for maintenance issues or changed loads. Seek competent mechanical or tyre advice rather than trying to diagnose a safety-related fault from the calculator.
Common fuel-budget mistakes
- Using the vehicle’s solo consumption while towing.
- Using only the map’s headline kilometres.
- Applying a city fuel price to a remote itinerary.
- Mixing kilometres per litre with litres per 100 km.
- Counting a budget margin as extra range.
- Assuming an app listing guarantees supply or opening hours.
- Ignoring the separate fuel used for unhitched sightseeing.
A practical fuel-planning checklist
- Log at least several representative towing fills.
- Separate towing and solo kilometres.
- List known detours and side trips.
- Check current route prices and appropriate fuel grade.
- Mark reliable fuel stops and conservative leg ranges.
- Recalculate after route, load or conditions change.
- Keep a financial margin and a separate physical fuel reserve.
Ready to build your fuel budget?
Gather the route distance, realistic towing consumption and a current planning price, then use the free Caravan Trip Fuel Cost Calculator. Pair it with the realistic caravan travel-day guide so the route budget and daily schedule describe the same trip.
The result is an estimate, not a promise of fuel use, price or availability. Explore the complete Caravan Calculator Hub for more Australian planning tools.
Frequently asked questions
How do I calculate towing fuel cost?
Divide trip kilometres by 100, multiply by towing L/100 km, then multiply by dollars per litre. Add explained extra distance and a budget margin.
How much more fuel does towing a caravan use?
There is no reliable universal percentage. Measure your combination or use a cautious range until you have fill records.
Should I use the highest fuel price on the route?
Use route-relevant prices and test a higher-price scenario. A single maximum can be unnecessarily blunt, while a home-city average may understate remote costs.
Does the calculator include fuel availability?
No. Confirm suitable outlets, hours, road conditions and range separately.
Sources and planning note
Last checked: 12 August 2026.
- ACCC — Fuel prices in regional locations
- ACCC — Fuel price apps and websites
- ACCC — What affects fuel prices
This article provides general budgeting information. Use current route information, vehicle manufacturer requirements and your own measured consumption. Do not rely on the estimate as proof of range or fuel availability.