Most hire cars at Keflavík go back full, which means one last stop in Reykjanesbær before you hand over the keys. Icelandic pumps are mostly unmanned and card-only, and they want a four-digit PIN. Get that part right and refuelling takes ten minutes. Get it wrong at midnight and it becomes the worst part of the trip.
Plan on refuelling off-airport. There is no forecourt at the terminal, so the pumps drivers actually use sit in Reykjanesbær — the joined-up towns of Keflavík and Njarðvík immediately east of the airport, five to ten minutes away along Route 41 or the local roads just off it.
The names you will see across Iceland are N1, Olís, ÓB, Orkan and Atlantsolía. Some are full sites with a shop and staff during the day; others are bare unmanned forecourts, the format the discount brands mostly use. Pump prices differ a little and move around, so the gap on one 45-litre fill is small change rather than a saving worth a detour at five in the morning. Read the sign nearest you, not a ranking you saw online.
Direction matters too. Keflavík Airport sits roughly 50 km from Reykjavík, and Route 41 carries almost all of that across open lava with very little beside it. Fill before you leave the Reykjanes peninsula rather than assuming something will appear. The same applies on arrival: check the gauge before you pull out of the rental car park, because sorting out fuel at 02:00 on an empty road is nobody's idea of a first hour in Iceland. Our late-night pickup guide covers the rest of that arrival.
Most Icelandic forecourts are unmanned, and the pumps generally keep working when the shop beside them is shut. You pay at the pump, or at a standalone terminal serving several pumps, before any fuel comes out. No attendant, no cash drawer, usually nobody to ask.
The sequence is the same everywhere. Pick English, insert the card, enter the PIN, then choose a fixed amount in ISK or a full tank. Take the fixed amount and any unused balance is released back to your card; take the full tank and the terminal authorises a holding sum, then settles at the real figure afterwards.
Two habits save a lot of trouble. Read the word on the nozzle rather than the colour — bensín is petrol, dísel is diesel, and colour conventions are not consistent between brands. And confirm what your car takes before you leave the rental car park — the filler flap usually says. Misfuelling is a classic exclusion from collision waivers, so assume that bill is yours unless your contract says otherwise. Our insurance guide works through what those waivers cover.
This is where visitors get stuck. Unmanned pumps expect a chip card with a four-digit PIN. If your card lives on contactless and signature at home, sort that out before you fly. Cards that behave perfectly in shops are sometimes refused at a pump, and which issuers and products work changes over time, so carry a second card from a different network.
The fallback is a prepaid fuel card. Several chains sell them in fixed amounts at staffed sites, and they work at that brand's own unmanned pumps without bank authorisation — a clean answer if your card keeps being declined. Which brands offer them, and in what denominations, changes — ask at a counter while you have a person in front of you.
Rental companies sometimes hand over a fuel discount key tied to one chain. Whether you get one, and what it is worth, depends entirely on the operator, so treat it as a bonus rather than part of the plan.
Finally, expect a pre-authorisation hold: a pump can reserve noticeably more than the fuel you take, releasing the difference over the following days. It is normal, and separate from the security deposit held against the car itself, covered in the deposit guide.
Fuel is sold by the litre and priced in ISK, with petrol and diesel usually close to one another. Prices track world oil and the exchange rate rather than the tourist season, and they move often enough that any number printed in a guide is stale by the time you read it. Plan in litres, which do not change, and multiply by whatever the sign says on the day. The table assumes real Icelandic driving — headwinds, gravel, hills, heating on.
| Car and route | Distance | Consumption | Litres | Tank fills |
|---|---|---|---|---|
| Small petrol automatic, Ring Road only | ~1,320 km | 6.5–7.5 l/100 km | 90–100 | 2–3 |
| Small petrol, Ring Road plus detours | ~2,000 km | 6.5–7.5 l/100 km | 130–150 | 3–4 |
| Mid-size 4x4, plus Snæfellsnes or Westfjords | ~2,200 km | 9–11 l/100 km | 200–240 | 3–4 |
| Large 4x4 or campervan, highland-capable | ~2,500 km | 11–14 l/100 km | 275–350 | 4–5 |
The pattern matters more than the exact figures. Stepping from a small automatic to a big highland 4x4 roughly doubles the litres over a fortnight, which at Icelandic pump prices can outweigh the gap in the daily rate. When the bigger car earns its keep anyway is the subject of our guide to the best car for the Ring Road.
Full-to-full is the usual arrangement: you collect the car full and bring it back full. Do the final fill in Reykjanesbær, a few kilometres before the airport, and keep the receipt. Some contracts ask for a receipt from a station within a set distance or time of the drop-off, and that rule varies from company to company, so read the one you signed rather than assuming last year's applies.
Come back short and the company refuels it at a rate above pump price, often with a service fee on top. Those figures are set by each operator and printed in the contract, not fixed by any national standard. Prepaid fuel packages sold at the desk run the other way, letting you return the car empty for a price agreed up front — which only pays off if you genuinely arrive on fumes. The rest of the handover is in the car return guide.
Around the capital and along the south coast, stations come often enough that you can be relaxed. Elsewhere they do not. Treat half a tank as your trigger in the Westfjords, on the eastern fjords, across the north away from the main towns, and anywhere inland. On the F-roads themselves, count on no fuel at all — and those tracks open late, the earliest around the middle of June and the rest through to early July, depending on the route and the thaw. Plan the whole leg on what is in the tank when you turn off the tarmac, and remember that river crossings are never covered by rental insurance at any level.
Winter adds its own margin. Sitting in a queue behind a closed pass burns fuel, and a full tank turns waiting from a problem into an inconvenience. Winter tyres are required roughly from November to April, which our winter tyres guide sets out in full, and those are the months when you most want to check conditions before a long empty stretch. The road information line is 1777; 112 is the emergency number. Hire an electric car and the arithmetic changes again — charger spacing, cold-weather range and payment apps all need checking in advance, which we cover in our notes on electric car rental at Keflavík.
Not at the terminal. The stations drivers use are in Reykjanesbær, five to ten minutes away on Route 41, and that is where most people do the final fill before returning a car.
Assume yes. Unmanned pumps ask for a four-digit PIN with a chip card, and unmanned forecourts are the norm outside the bigger towns. Contactless is not something to rely on at a pump. If your card has no PIN, arrange one before travelling or buy a prepaid fuel card on arrival.
Check the filler flap and the rental agreement before you drive away, and read the words bensín and dísel on the nozzle rather than relying on colour. Misfuelling is a classic exclusion from the standard waivers.
Work it out on the day. A small hire car holds roughly 45 litres, so multiply that by the price posted on the pump. Icelandic fuel prices move with oil and the exchange rate, so any figure quoted in a guide is out of date before you arrive.
Rarely. A staffed shop will take cash while someone is behind the counter, but the unmanned pumps that dominate the network are card-only. Carry a working card, and a second from a different network as backup.