Sign up ×
User Experience Stack Exchange is a question and answer site for user experience researchers and experts. It's 100% free, no registration required.

Many cars, such as the BMW M3 pictured below, have their fuel door on the passenger's side of the car.


I do not understand the reasoning behind placing the fuel door opposite the driver; placing it on the driver's side seems more logical to me, as the driver is then closer to the fuel door and does not need to walk around his/her car in order to refuel.

How does placing the fuel door on the passenger side improve the experience of the cars' users?

share|improve this question
Note: I am aware that the BMW M3's fuel door is on the driver's side in countries that drive on the left. In these countries, many cars still have the fuel door on the passenger's side, albeit on the opposite physical side of the car pictured above. – Vulcan Feb 25 '14 at 3:34
No sources, so it doesn't qualify as an answer: I think it is actually easier. You usually pull up quite close to the actual pump installation, especially in narrow-layed out stations. That means that if you have the pump on the same side as the driver seat, you will have very little space to get out of your car. Getting out on the other side would give you more space, I think. Just a guess though. – André Feb 27 '14 at 9:29
From the perspective of user experience I'd say that question should actually be: "Why are there no cars that have fuel doors on both sides?". Ok, the cheap cars don't have this because its more expensive, but luxury cars? – yankee May 2 '14 at 21:19
@yankee That would take away from the aesthetic of the car, and is highly unnecessary in this day and age when people can always pull up their fuel door to a pump regardless of which side the fuel door is on. – Anindya Basu Jun 12 '14 at 16:47

6 Answers 6

up vote 12 down vote accepted

I asked my father just this question forty years ago. His answer then was that it was a hangover from early designs, particularly when petrol stations looked like this:

Store and petrol station

Most drivers pulled in at a pump on their side of the road, which means that most arrivals would have the passenger side of the car adjacent to the pumps. It was all attended service, so the driver didn't have to get out at all.

There is a lot of inertia in physical design. It took a very long time for steering-column stalks on British cars to be set up the same way as other countries' cars with the indicators and lights on the left and wipers on the right — and that change was arguably rather more important. Flash the headlights or squirt the windscreen?

These days, with self-service and different petrol station design, and cars being imported from all over the world, it's less important to cater for the particular instance illustrated. But then again, because cars can pull up at either side of pumps nowadays, there's not really much necessity for each manufacturer to change their own practice.

Illustration: Dan Lockton

share|improve this answer
And yet, that change you refer to in British cars annoys the hell out of me on a regular basis. It effectively makes it impossible to reach for the gear-stick AND turn on your indicators at the same time. Which is something I want to do almost every single time I've come to a complete stop at a round-about where I want to leave in one of the first two junctions. I guess that's OK though, since around 70% of people here seem to never use the damned things anyway. </rant> – Thor84no Dec 8 '14 at 16:02


Putting fuel filler doors on different sides of different cars thus means that some cars can access pumps from the left. And this makes it less likely that drivers will have to wait in line for gas. That benefit greatly outweighs the cost of occasionally pulling up to the wrong side of the pump in a rental car.”


For safety reasons, automotive design engineers tend to locate the fuel tanks, pipes and filler ports on the opposite side from the car’s exhaust system, except in the case of vehicles with dual exhausts.


Why don’t all cars have the fuel filler door on the same side? The driver’s side would seem to make the most sense.

This might explain why most Japanese cars have it on ‘our’ passenger’s side — it’s ‘their’ driver’s side.

Doesn’t explain why most German cars have it on ‘our’ (and ‘their’) passenger’s side. Since I’ve largely owned German cars, this seems perfectly natural to me.

TL;DR: There are multiple reasons why gas intakes are on one side versus the other, but it has nothing to do with "user experience". The Google search I did yields much more information on - Why is the gas on the other side of the car; or Why are fuel doors on different sides.

To make your life easier, on most (perhaps all) newer model cars, there is a little arrow next to the fuel icon to tell you where it is:

share|improve this answer
Some great research here, and I'd give you an extra upvote for the 'the google search I did yields much more information' comment - makes it seem like the OP didn't actually do any research before posting the question in the first place. – JonW Feb 28 '14 at 15:39
@JonW Before asking the question, I did do research and one source I read was the PBS article linked in this answer. While that article addresses ux-related topics the most, I didn't value it's argument that having gas tanks on the opposite side allows more drivers to refuel simultaneously, as it isn't particularly difficult to go around a pump in order to reach the opposite side, and the cyclical approach to having all fuel doors on one side when refueling seems quite natural (see image). – Vulcan Mar 1 '14 at 3:03
Otherwise, I read several articles about the fuel door being opposite the exhaust system or the car originating in a country that drives on the opposite side, but both have counter-arguments. The exhaust system can be moved to the passenger's side to allow the fuel door on the driver's side, and many cars are designed with fuel doors on the passenger sides in their native countries (see: Germany). After concluding that each resource I found wasn't helpful, I assumed (possibly incorrectly) that there may be a user-experience factor I was unaware of, so I asked a question here. – Vulcan Mar 1 '14 at 3:14
I have blown some people's minds showing them the little arrow on the fuel gauge as OP mentioned. :) – Max Jun 11 '14 at 23:23

Many cars are now constructed so that they can trivially be made either right-hand or left-hand drive, just by swapping same-sized pods in the dashboard. It is less trivial to swap the fuel filler and exhaust systems, which as someone said, try to be on opposite sides. In other words, there is no reason, and it is "same side" or "other side" depending on the location that the car was assembled to be used in. People DO care which side they drive on, but they really don't care which side the fuel filler is on, except that they have to keep remembering, especially when they own two cars with it on different sides. I find the tiny arrow on the gauge to be confusing. You know, the fuel filler used to be smack in the middle. Why was that changed? Why did the high beam switch get removed from the floor? Why did only one car I ever drove have a "bump to the next radio station" button on the floor? It was the best idea I ever saw. I have only seen one wristwatch with a ring instead of buttons. This is definitely not survival of the fittest, more like trial by inertia.

share|improve this answer

This was discussed on Car Talks this past weekend. One of the brothers (forgot which) mentioned that German engineers have, for years, considered that placing it on the passenger side was superior for emergency situations when you have run out of gas and you need road-side fill-up.

By placing it on the passenger side there is less chance of being hit by a car on the highway. Both brothers laughed at this arguing that the utility of having it on the driver side outweighed the few times (if ever) that one was dangerously parked on the side of the road due to running out of gas.

share|improve this answer
Very good (and new!) point, Car Talks is one of my favorites. +1 – Vulcan Dec 8 '14 at 20:27

The fuel door isn't on the drivers side because they park very close to the fuel pump. If the fuel door is on the same side with the driver door, then you can't get out of the car... fuel pump border

share|improve this answer
My fuel door is on my drivers side. The question is "why aren't they always on the same side", not "what side is yours on" or "what do you think is best". There are a multitude of cars in either category. – Evil Closet Monkey Jun 12 '14 at 16:53

The vast majority of people enter a gas station from only one direction already; people have a very strong statistical tendency to enter a gas station by turning right (rather than crossing traffic turning left). This leads most people to be entering from the same direction. They can only access one side of the pumps without turning around on the station's lot.

If you have all the fuel doors on the same side of every car, then everyone will have to use the pumps on one side, or turn around.

Pumps on only one side, or fuel doors on only one standardized side, would lead to more maneuvering and a less efficient fueling experience.

It should be noted that more efficient traffic patterns at the gas station are only a symptom of fuel doors being on either side, not the cause of it. No one decided that they could improve traffic by putting fuel doors on different sides of different cars. It's just an unexpected benefit.

share|improve this answer
Can you point to the studies showing this "statistical tendency"? It doesn't matter if you turn left or right into a gas station, your car is always pointing the same way when you enter the station from a given entrance. Since gas stations are commonly built on corners, with an entrance on both intersecting streets, making a right turn (or left turn) doesn't mean anything when two people enter from different entrances -- they're still pointing different directions. – Evil Closet Monkey Jan 5 at 23:02

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.