I normally sleep alone, but when I do occasionally share a bed, I have to sleep on the left. I sleep on my left side most of the time, and there has to be free and clear air facing me, not another person’s body. Hell, even when I sleep alone, I’m so close to the left side of the bed that I’m almost falling off.
I sleep on the side that’s nearest the door. Right now, that’s the right side, and I only occasionally share the bed, since our daughter moved out my husband and I sleep in separate rooms because of our vastly different schedules.
I don’t really care which side of the bed I sleep on, but I prefer to sleep on my right side in a fetal position.
I will explain “other.” Every now and then we do something radical in bed; we switch sides.
We do this because the mattress sags on his side. Switching the mattress regularly, it still seems to sag on his side.
Also, are we talking left while facing the bed, or left while lying in it? Because I’m on the right while actually in the bed (right now) but it seems to be like I get in it from the left side because I approach it from the foot.
Confused? Yes, I guess I am.
F, married for a gazillion years.
Currently on the right side of the bed. Every year or so ‘She Who Must be Obeyed’ will decide to re-arrange the bedroom, and then who knows. It doesn’t really matter to me.
The most important thing is to not be left with the freedom to have the whole bed to yourself, that sucks.
I think you’ll find a much stronger correlation between gender and side closest to the door.
My last relationship found me on the side closest to the door. His logic being if someone breaks in to kill us I get offed first. So it varied based on how the bed was set up.
Would that be “on the right” from my perspective as I am stretched out supine on my back facing the ceiling in the bed? Or “on the right” from my perspective as I am sprawled out prone on my belly with my pillow before me?
Or perhaps you mean “from the perspective you would have if you are standing up and FACING the bed, from the foot of it, staring towards the head of the bed”… ?
You need to define your terms 
EDIT: oh! Hmm. In that case, on the right. Male.
I sleep on the left side of the bed and I lay on my left side. And I’m left-handed.
Female, and whichever side is closest to the bathroom is mine.
In the middle between the twin models. And then when I wake up I’m alone on the right.
One of the things that surprised me about Married Life was that Pepper Mill knew exactly which side of the bed was hers, and I got no say in this. I don’t resent it or anything – I’m just surprised that she had so definite an opinion. To me it wouldn’t matter one way or the other.
The exception is when we are traveling, and there’s a light on only one side of the bed. I usually sttay up later reading, so I get the side with the light, whichever side it’s on.
This would be a consideration for me, if our bed was right against the wall on ‘my side’, as then I’d have to climb over him to get to the bathroom in the middle of the night. He has to get up occasionally to use the bathroom in the middle of the night, I have to get up at least once, sometimes twice. Fortunately for us, our bed is located in such a way that both of us have space to get up on our own side, so it’s not an issue.
Hey, we used to have a bed that did this, and my hubby diagnosed the problem as the box spring. Until we could afford a whole new bed, a piece of plywood placed between the box spring and mattress worked wonders!
It depends on two factors, namely which side is closest to the bathroom and which person is most likely to need to go there in a hurry.
Male- on the left. It started this way b/c the first couple places we lived, the bathroom was on the other side of the bed and she wanted direct access to it. But now that we’ve moved, the bathroom’s on my side, which actually works out well b/c with this damn BPH, I’m the one getting up frequently during the night.
I didn’t know exclamation points and commas slept!
The things you learn here!
As to sleeping habits, I am usually nearest the door, but I’m flexible. Wife and I were at a lovely bed and breakfast recently and we just (I think unconsciously) grabbed the sides of the bed equivalent to where we’d be at home, but the door placement is reversed. Other times we’ve been out, bed position has been reversed.
We’re going to a hotel again tomorrow night, I’ll update then.
I sleep on the side away from the door. He sleeps closer to the door. I have done this with two husbands, a fiancee and a long term boyfriend. It’s a protection thing for me - I want someone that will fight off the intruder before it gets to me.
I knew this LTR was a keeper when he asked without prompting: do we need to switch sides because of the low placed window, because that’s more likely for an intruder? 
And then I had to reason with him the logistics of climbing into the window vs. breaking down the door.
FWIW: I’m a pretty normal person. I have no idea why I have this quirk and need for protection from a “big strong man” - I am usually very capable of handling things myself during daylight hours.
The men in my life have seemed to want to sleep closest to the door. So I’ve slept on the left or right, depending. My now husband is left handed so sleeping on the right has other, um advantages 
Of course they sleep! Why do you think there are so many mis-used asterisks in the world? Because that’s when the exclamation points are asleep! Duh.
To us, it doesn’t matter where we’re in bed. In a hotel or B&B, we will stand at the foot of the bed and figure it out. As you face the head of the bed, I am on the right-hand side. This is important, because we frequently make love in the “spoon” position, and in order to competently do so, must both be laying on our left sides. We’ve done it (under extenuating circumstances) on our right sides, but it just doesn’t ‘feel right’. Go figure. 