Can an economy passenger come up to business class to join a family member? If a husband and wife split up – he takes the first class seat, and she’s stuck in coach – can they squeeze into the same seat up front, or take turns using it?

Officially, no. But it happens. And one flight attendant allowed it. A crewmember shares,

I work for an airline with lay flat seats. Had a guy who’s wife was in economy and he brought her up so they could sleep together. When we noticed, they were ugly sleeping, mouth wide open.

I’m a coach roach but I’ve been working first class lately. Typically I just defer to the lead but today I was the most senior in first class. I said they had to separate cause if we hit turbulence, It’s only for one person, but the senior mama in the back was like “as long as theyre not being a bother” and I’ve definitely seen leads allow it.

Generally the rules are that safety doesn’t allow it.

• Most seatbelts and seats are certificated for one passenger only. This is for belt strength and structural load limits. (There are exceptions where seats have more than one seat belt.)

• There’s generally only a single oxygen mask per seat.

And airlines want to enforce their revenue rules. Passengers are supposed to remain in their ticketed cabin. Any allowed visiting up-front is supposed to be limited and temporary. If two people want business class, both need to pay for it.

Other passengers may also see it as a degradation of the service they’re buying – privacy and quiet, versus the extra foot traffic of people going back and forth.

Several flight attendants responding to this story suggested they’d file an incident report, referring it to corporate security.

You’re generally expected to remain in your ticketed seat and cabin for the whole flight. That became stricter after 9/11. I do vaguely recall though Delta permitting one-time seat swaps between cabins after takeoff, but before the first meal service. Delta regulars can confirm if this is still allowable. Foreign airlines are often much stricter, protecting the exclusivity of premium cabins tha are far nicer.

That said, flight attendants often have discretion and enforcement varies. It’s best to asked nicely, and limit your request for instance to a single swap rather than moving back and forth and only do it at cruise altitude while the seat belt sign is off.

If you want to spend time with someone in another cabin, you can probably move down a cabin more easily than up. So go visit someone in coach. I’ve never been questioned walking the aircraft when flying a premium cabin whereas I probably would be questioned walking to the very front of the aircraft. (My son is one year old and if he’s ever fussy he’ll immediately go quiet walking around the aircraft.)

Speaking of moving down a cabin, I’ve brought colleagues snacks and drinks before without issue, though that potentially creates the uncomfortable situation where coach passengers see someone getting special treatment around them that they don’t.

There are times when a coach passenger might move up to a premium cabin briefly, and no one will look askance at it.

• A child is in coach, maybe with another parent or nanny, and they need comforting from the parent up front.
  
• The passenger in the lower cabin comes up for a drink. Perhaps not officially in the rules, but for years British Airways crew have often allowed it.
  
• This is especially the case on planes where there’s a second seatbelt and an ottoman or bench designed for multiple passengers in the same seat area (although really designed for other passengers trveling together in the same cabin to use).

Bottom-line is that in most cases if you attempt to lie together in the same seat, expect the crew to intervene. At most, a flight attendant would tolerate a brief snuggle or a photo, but anything longer is likely to be stopped. Stories are legion of amorous couples getting a gentle “please return to your seat” request.

A few airlines offer special setups that create a double bed. Singapore Airlines A380 Suites can be combined into a double suite with double bed.

Etihad’s A380 First Apartment allows the wall between seats in some rows to come halfway down, so that passengers in bed mode and lie down next to each other from the waist up. That lets passengers assigned to those seats share a space.

Etihad’s Apartment also has seatbelts for the bench that folds out into the bed (that’s separate from the seat).

Qatar Airways Qsuite business class has middle seats that convert into a double bed for couples who both hold tickets in that cabin.

Some premium cabins have a small “buddy seat” or ottoman that allows a second person to sit briefly (often used for dining together). British Airways first class and Virgin Atlantic business class have an ottoman with a seatbelt.

Cathay Pacific first class has a seatbelt at the ottoman for passengers in the cabin to dine together – they also have a table extender so that both passengers have full-sized tables, attached, so the dining isn’t cramped and the experience is more like a table in a restaurant.

While airlines usually forbid economy passengers from joining others in premium cabins as a formal policy, enforcement varies, and a polite request sometimes works. Trying to squeeze two people – from a different cabin – into a single seat generally crosses the line.