Debate has kicked off after a man shared online that he charged a “very obese” plane passenger for taking up part of his seat.

Reddit user BigBawluh said he was getting comfortable ahead of a “long five-hour flight” in the US when he spotted his row-mate boarding.

He said that when the man sat down he was “seeping into about one-third of my seat” and that he was “pressed up against him”.

After a minute he decided to “be upfront”, telling him: “Sir, I’m sorry but this situation is not working for me, you’re taking up quite a bit of my seat.”

“He wasn’t rude, but sort of gave me a shrug as if there’s nothing he can do — although he did sort of tighten his arms in to try and be narrower,” the aggrieved man said in his viral post.

“It just wasn’t enough, though. He still was overhanging over the armrest about 1/4th into my seat even when squeezing his arms in. I’m talking about fully hanging over the armrest into my seat.”

“BigBawluh” said he got the attention of a flight attendant to try and sort the issue.

But when it became clear there were no open seats - and not wanting to make the man wait for another flight - he asked for compensation.

“I told the guy, ‘look, I’ll put up with this if you give me $150 (AUD $211) — that’s half the cost of this flight and that would compensate me enough for the circumstances’,” he said.

“He instantly agrees, pulls out cash and pays me. He even told me he appreciated it.”

He said it was a “win-win” as it gave the passenger a “valid option to stay on the flight and I was compensated for literally having only 75 per cent of my seat, max”.

“He wasn’t angry at all. If anything he seemed quite relieved we could work it out privately,” he said.

The reaction however was mixed.

Reddit user Clocksailor argued the problem “was that this large dude stuck you with being uncomfortable on your flight”.

“Well, the $150 didn't make you any less squished in your seat, so it really feels like you just blackmailed this guy for being fat,” they wrote.

Others sympathised, believing it was a reasonable outcome.

“(Original poster) let the guy stay on the flight, have enough room to accommodate without paying for two seats and without the embarrassment and inconvenience of having to get off and wait for the next flight that wasn't fully booked,” herefromthere posted.