A bathroom mirror does not have to be the same width as the vanity. A slightly narrower mirror leaves room around the edges and nearby lights; an equal-width mirror creates a fuller, more continuous look. A wider mirror can work on a broad feature wall, but it needs enough clear space and a layout that feels intentional.
Use the full vanity cabinet width as the starting point, then check the basin position, users and surrounding fittings. The sink bowl and the vanity are different measurements, as our guide to mirror width versus sink width explains.
Compare the three approaches
On a small screen, swipe the table to compare all columns.
| Approach | Best reason to choose it | What to measure |
|---|---|---|
| Narrower than the vanity | A lighter outline or room for wall lights. | Margins beside the mirror and usable reflection. |
| Same width as the vanity | A continuous, structured focal point. | Frame width, wall returns and cabinet doors. |
| Wider than the vanity | A deliberate feature across a larger wall. | The complete wall composition, not only the basin. |
There is no single percentage that suits every bathroom. A useful way to judge the choice is to mark two or three outlines on the wall. Our mirror size calculator helps compare the proportions; it does not replace the room measurements.
See what the difference looks like in practice
60 cm round dual-light mirror — £128. On an 80 cm vanity, a centred 60 cm circle leaves 10 cm on each side. Its curved edge gives a softer finish, while front and rear lighting bring practical illumination and atmosphere together.
60 × 80 cm dual-light mirror — £129. The same 60 cm width creates a taller reflection in portrait orientation. Choose this shape when height matters as much as the horizontal margin.
120 × 60 cm dual-light mirror — £249. A full-width option for a 120 cm vanity, or a narrower feature on a wider unit. Mark the whole footprint and check nearby lights before committing.
Prices and stock checked on 27 October 2026. Listed prices are before any checkout promotion.
Frame, shape and lighting affect the result
A frame adds visual emphasis and may reduce the visible glass area within the overall dimensions. Frameless designs can feel lighter, but they still need the correct mounting and clearances. Compare square mirrors, arched mirrors and rectangular mirrors using the outer size.
Light direction is a separate decision. Front illumination helps light the viewing area; backlighting creates a wall glow. Review vanity light placement alongside the mirror. If you are considering adding lighting to a mirror you already own, read round mirror lighting options before modifying its construction.
Single and double basins need different comparisons
For two basins, try one broad mirror and two separate outlines on paper. A continuous reflection can unite the vanity; separate mirrors can centre each user’s space. Neither arrangement is automatically better. A mirrored cabinet also needs door-opening and depth clearance, not just a matching front width.
Browse large illuminated mirrors for broader layouts. For specific examples, read our 48-inch vanity sizing guide and guide to mirror proportions above a vanity. The right choice gives you a comfortable reflection and a wall that feels balanced every day.