Personally I would leave the laundry in the basement. If the washer fails or hose breaks on an upper floor, then the water will flow through those floors. If a fail happens in the basement then it's contained to the basement.

I have a large, 3 story house with a large family... we are about to downsize, all of our kids are young adults/adults now. I taught mine all to do their own laundry by the age of 13 at the latest. Most of our bedrooms are on the third floor, including the master, but our boys (3 of them) all slept in rooms in the basement. All of that to say that we were scattered all over the house and had bathrooms on every level of the house. Our laundry room is on the 2nd/ main floor (no bedrooms on that floor, but where we spend most of our time) and I’ve been perfectly happy with that! I haven’t minded schlepping dirty or clean laundry to a different floor, but I’m quite sure I would’ve been irritated with having to navigate stairs to check on my laundry. So I say to put your laundry on the floor where you spend the majority of your day if you’re the type that does your laundry during the course of the day. (I was a homeschool mom for almost 2 decades so home all day) If you do your laundry at night then my advice would likely be different. Of course, I always fantasized a little about having 2 laundry rooms... one on the main floor where the kids could do it and I could do my kitchen laundry (dish towels, cleaning rags...) and one where I could do my own laundry without having to set aside days for my kids to complete theirs. (We all had assigned laundry days during their preteen/teen years)... but that would’ve been quite a luxury. :)

Oh, wanted to add... as a mom of a large family I would NOT have wanted everyone’s laundry taking place in my master bathroom. I would, however, have zero issue with telling my kids that they could do laundry in the basement and have an extra laundry room in my master bathroom just for me. LOL!

I wouldn't want the laundry near any bedrooms because I usually set mine to run overnight, so I'd leave it in the basement. Of the two options you list, I'd say the second floor sounds better. It makes it more accessible to more people. If you can run to two laundries then one in the basement and one in the master suite would work.

Of the two choices, 2nd floor. You don’t want to be running from the first floor to the third to change a load of laundry. And, in a family house, most of the laundry, including bed and bath linens, will be from the 2nd floor, plus towels and miscellany from the first floor. And even if it’s just you in the house, you are going through the second floor anyway a few times a day.

But, IN the bathroom? Is there a way to avoid that?

Thanks to everyone for the feedback. Keeping it in the basement is out, because when I’m living there alone almost all the dirty laundry will be coming from the third floor, and I just don’t want to run up and down to the basement all the time. (I’ve also lived for years in condos and apartments with laundry on upper floors, and an automatic water shutoff tied to a flood alarm brings great peace of mind.) (And the connections will be down there if a future owner wants to move it to the basement.)

But you’ve all confirmed my instinct that the second floor is the better choice. I still have to consider the practicalities of plumbing and cost, but unless it’s impossible or too expensive to put it on the second floor, that’s what I’m planning on.

Thanks again for sharing your thoughts.