Is it "acceptable" to finish this quilt with 3 borders on 3 sides (not on the top)?
 

This was to be my daughter and SIL's Christmas present, then life got it the way! I want it finished and gone to the long-arm quilter!

I didn't want to make the braid portions extended over the end of the bed, and hated to cut them off to center them, with all the borders all the way around. I added the border to three sides (so the quilt would go under the pillows). The top just has the dark brown "sashing" on the top. It will be bound with that same brown. Opinions please!

It will be fine. I just did the same to my bitty blocks quilt. Antique quilt have only 2 borders on some. With the bed against a wall that side did not need borders. Love the colors in your quilt

Nothing wrong at all with borders on three sides. I have seen antique quilts that were made to go on a bed that is against a wall and the quilt did not have a side that went against the wall. Everything works for a purpose. The quilt is wonderful and I love the colors.
peace

Of course it's acceptable! It's your quilt & your decision. The only thing I might suggest is adding an extra 1/4" of the brown to the top so when you apply your binding (assuming you're using traditional 1/4" binding) so that way you still will see the full width of the sashing. Of course, it's completely your decision & if you're fine with skinnier sashing on the top, that's a design choice and I fully support it! At least with matching brown binding, it will blend together.

Actually I prefer it with borders on three sides. You know right away where the top is. My store bought king size comforter is kind of that way no trim on the top edge.

My only thought is that maybe you'd want a narrow, maybe 3" border at the top to give you something to grab on to when you are pulling the quilt up or making the bed instead of putting a strain on the diagonal piecing.

I had a similar situation and just could not bring myself to do the 3-sided border. I added the 4th side and made it monster-big. The decision suited my need for symmetry. Sorry I know this doesn't help you much. Just saying, if it were me, I'd add the remaining border.

it will look fine, love the colors and the natural stone look of some of them.

Being a symmetrical person I would have to put a 4th border on. With 4 borders the quilt can go on either way and save on pressure points.
at the end of the day it is what you want to do and your daughter wants.
love the colours and pattern.

I like to turn my quilts around on the bed to help with even wear and even fading. But you know best how they will use the quilt, where it will go, and how you want it. Do what you think is best! It's lovely.