The frame makes the mirror looked finished, to me. Just having a mirror will reflect the light, and I'm sure will be sufficient enough to achieve the effect of making the room appear larger. I'd frame it, though certainly there is plenty of room for personal preference here, and I think your preference is important, too.

I love the look and practicality of a frameless glass mirror in a bathroom. Less visual clutter and easier to clean I like the sconces attached directly to the mirror for a more finished look.

I was envisioning the first image Mrs. P posted when you mention one full wall. If not than yes I would frame it too.

A framed mirror can add to a theme or jazz the room up a bit. White look yile like marble and mother of pearl shell are light in color which would keep the room feeling larger.

I like the uncluttered, clean look of frameless mirrors in a small bath. But, I would take it to the ceiling and mount the light (whether it's one centered light or 2 sconces - which if it's a small bath, you may not have room for) right to the mirror.

I am reading this thread for current preferences.Not trying to jack it but the mirrors are what I am thinking of removing! I am planning a master bath remodel. I currently have a recessed 76 inch vanity with a full wall mirror behind the vanity and 1 the deepth of the vanity on each side. So basicaly the first pic with Mirrors on the sides as well, vanity to ceiling. I thought this was a very dated look.?? The lighting is pot lights above the vanity. I was going to take down the mirrors and replace with either one large mirror with center mounted sconce behind vanity and matching sconces on each side retaining pot lights above. Or replace mirrors with 2 smaller mirrors, 1 behind each sink with a sconce in the middle and on each side. The mirrors would not be vanity to ceiling, just normal size with either tile or wood trim on the wall to surround. If people still like that huge mirror look I could leave the vanity and mirrors and just change out the vanity top, remove 4x4 grouted tile top! Thoughts?

@raebutt I think the previous comment was for a small bathroom. If you have a small room like in a closet sized half bath, large mirrors do make it feel larger. Builder basic mirrors are a bit dated, but a lot of that is due to wear and tear. Many builder grade mirrors like the ones in my 30 year old town home have wear on the back since moisture has gotten to it. I'm not removing mine, since it's a hassle. I'm going to add a tile frame to cover the wear with inoxia speedtile. The color I am using is thin vein cut marble tile (real stone) that has an adhesive attachment, so no grout or mortar. It's all about the finished look. Go with what you can afford and what you like as you are the one who has to live with it.