Full to full: the most transparent rule
You collect the car with a full tank and return it full. You pay only for the fuel you use, at a filling station of your choosing, so the price of the fuel does not depend on the rental company.
The delicate point is the final refuelling: fill up close to the return point and keep the receipt. If the needle does not read full, a shortfall charge plus a service fee can apply.
Full to empty: the tank is paid up front
Here you buy the whole tank at pickup and may return it as empty as you like. Unused fuel is generally not refunded, so the policy only makes sense if you are confident of using nearly all of it.
The price per litre is set by the company and a service fee is often added. On short trips this policy works out expensive, because you pay for fuel you end up handing back inside the tank.
Same level: convenient and hard to prove
In this variant you collect the car with a part-filled tank and must return it at the same level. You avoid paying for a whole tank up front, but the gauge needle becomes the only reference available.
The gauge is not precise and the reading can shift with the slope of the ground. It is therefore worth photographing the dashboard with the ignition on, both at pickup and at return.
Where the costs hide
Besides the fuel itself, a refuelling service fee, a per-litre rate above the pump price, or a minimum amount even when very little is missing can all apply. These items sit in the terms, not in the headline price.
As an illustration: if ten litres are missing and a high per-litre rate is combined with a service fee, the final amount can comfortably exceed what you would have paid by filling up yourself before handing the car back.
Check the level at pickup, not when you set off
Before leaving the parking bay, switch on the ignition and check that the level matches what the contract states. If it does not, have it corrected in writing on the handover document before you move.
Adding a note later is difficult to insist on. A minute in the car park saves you arguing about the difference at return, when you can no longer prove how you received the car.
The right kind of fuel
Check the contract and the fuel filler flap for whether the car takes petrol or diesel, and whether it is a hybrid or electric model. Filling the wrong fuel is generally excluded from any cover.
If the car is electric or a plug-in hybrid, the equivalent rule concerns the state of charge and the cable supplied. Clarify before setting off what percentage it must be returned at and which connector it uses.
The final fill: close by and with a receipt
Refuel near the return point rather than halfway there: with many miles still to cover, the needle can drop far enough for a shortfall charge to apply.
Keep the receipt showing the date, the time and the address of the filling station. It is the evidence that the tank was full shortly before you handed the car back.
Tank size changes what a policy costs
The same policy translates into very different amounts in a small city car and a large estate or four-wheel drive. Under full to empty the sum paid up front depends directly on tank capacity, so the risk grows with the vehicle class.
Knowing the approximate tank size and typical consumption when booking makes it easier to judge which policy suits your route. On a short trip, paying up front for a large tank is usually a poor deal.
Document the return as well
Photograph the dashboard with the ignition on as you hand the car back, so that the level and the mileage are both visible. On an out-of-hours return that photograph is often the only record of the actual state.
Add the return receipt issued by the staff. If a fuel charge appears later, those two pieces together allow you to support a dispute.
Compare the policy, not just the price
When comparing, note which policy applies, what service fee it carries and what per-litre rate would be charged. A full to empty offer can cost more over a short weekend than a slightly dearer daily rate on full to full.
The planned comparison intends to show the fuel policy next to the price from the end of 2026. Until then the detail has to be looked up in the terms of each offer.
Checklist
- Identify which of the three policies applies before booking
- Check the service fee and per-litre rate in the terms
- Verify the tank level with the ignition on before setting off
- Have any difference corrected in writing on the handover document
- Confirm in the contract whether the car takes petrol or diesel
- Clarify state of charge and connector for electric or hybrid cars
- Refuel near the return point rather than halfway there
- Keep the receipt with date, time and filling station address
- Photograph the dashboard at return as well
- Keep the return receipt together with the fuel receipt
- Ask for the approximate tank size when booking
Frequently asked questions
Which fuel policy is cheapest?
Full to full is usually the most transparent, because you pay only for what you use at a station of your choosing. Full to empty only pays off if you are confident of using nearly the whole tank.
Is unused fuel refunded?
Under full to empty, normally not. The tank is paid for in full at pickup and unused fuel is not returned. It is therefore worth estimating your planned mileage beforehand.
How do I prove the level the tank was at?
With a photograph of the dashboard with the ignition on, at pickup and at return, and with the receipt from the last fill. Those are the pieces of evidence any later dispute rests on.
What is a refuelling service fee?
An amount the company charges for filling the tank on your behalf, on top of the fuel itself. It often applies even when little is missing and appears in the terms, not in the headline price.
What happens if I fill the wrong fuel?
That damage is generally outside the cover and the costs fall on the driver. Check the fuel type in the contract and on the filler flap before the first refuelling.
Is it enough to fill up on the way to the airport?
It depends on the distance. If many miles remain, the needle can drop far enough for a shortfall charge to apply. Refuelling near the return point is safer.
How does the rule work for an electric car?
The reference is not the tank but the state of charge the car must be returned at, along with the cable handed over. Both points are worth clarifying before leaving the branch.
What if the tank is not as full as the contract says?
Have it corrected in writing on the handover document before leaving the bay. A later dispute is hard to sustain without that note or a photograph of the dashboard.
Can I change the fuel policy at the counter?
Rarely. The policy is part of the rate you booked and is generally fixed by the time you collect the car. If it does not suit you, choose a different offer before booking rather than relying on negotiating later.
Does the level still count on an out-of-hours return?
Yes, and in that case the check is made later without you present. That is why the dashboard photograph with the ignition on and the receipt from the last fill matter especially on a night-time return.