Commercial airlines have mandated assigning seats since the beginning of the airline industry. Except for very few carriers, like Southwest Airlines, most flights come with a specific seat assignment.

For most travelers, this is neither surprising nor confusing, but you’d be surprised how often travelers forget, change, or even totally disregard their assigned seat. People move seats all the time, on nearly every flight. So it’s no big deal, right?

Here’s why moving your seat on a plane can be inappropriate, and when it’s okay to do it.

Unknown Expectations

According to one flight attendant and TikTok user, it is a big deal. In a now-deleted video, TikTok user @destanieaaa shared an experience where someone asked if they could move seats. She told them no because she was expecting a full flight. 

When she walked away, she said, the passengers moved anyway. The flight had not yet taken off and the cabin door was still open. Shortly after, other passengers, likely also unaware that more people were expected, began to move, too. She said the passengers who had moved were getting comfortable in seats that did in fact belong to other people who simply hadn’t boarded yet.

Before long, the flight attendants had to make an announcement reminding everyone to return to, and remain, in their assigned seats.

The TikTok user noted that instances like this can make a flight attendant’s job harder.

But, seriously…is it really that important?

Avoiding Disruption

The answer is… (mostly) yes. There are three major reasons it matters: moving can be disruptive to the cabin; it can impact the plane’s balance; and it could be against the airline’s policies.

First, moving can be disruptive. If one person moves, another might want to move. And so on. Then, before the flight lands, lots of people are up and moving around which is not ideal for a flight. It can also create conflict. A person might be moving into a seat or row that other people don’t want them to be in. While these issues are usually settled quickly, it does create more work for the flight crew who, contrary to popular belief, aren’t there to resolve seating issues.

Second, the plane has to be balanced for smoother flying. While seats might appear empty and open for the taking, the flight crew has internal responsibilities related to balancing the plane that passengers are often unaware of. If there are 40 people on the left side and nearly the same on the right, just a few people moving seats could impact that even weight.

Third, some airlines have specific rules about swapping seats. Some even explicitly forbid it without paying an extra fee or getting the permission of a member of the flight crew. Ignoring the policy can mean risking being able to fly with the airline or being assessed a fee later.

The Right Way and Time

The easiest way to secure a seat change is to have it done formally, before the flight. This can be done either through the airline’s app or website or with a gate agent or customer service representation before checking in to the flight

Another way to secure a move is to ask a flight attendant, The timing of the ask depends on the circumstances. If boarding seems to be nearing its end and there are many seats open, it’s okay to ask the flight attendant before the door closes. This doesn’t mean a guaranteed “yes,” but the flight attendant will determine whether, or when, the move is possible. 

On the other hand, a delayed flight that has a rushed boarding or feels chaotic might not be the best time to ask. In situations like this, it’s probably better to observe where a seat might be open and ask after boarding is complete.

If the flight is completely full, it’s probably best not to ask.

The last way to secure a potential seat move is to ask a fellow passenger. Rather than shouting ” Does anyone want to trade seats,” it’s best to ask a specific passenger if they mind swapping. And it’s easier to do an equal switch. This means you’re in an aisle seat swapping with another person in an aisle seat, or you’re in economy swapping with someone in the economy. Be realistic and fair. A middle seat in economy isn’t really a fair, or realistic, trade with a window seat in business class, or extra legroom seating.

Overall, it’s possible to move seats on an airplane; just get permission, be realistic, and don’t be disruptive.