Ridge filler

A ridge filler is a base coat that contains fine particles such as silica or talc, which settle into vertical ridges on the nail plate and dry to a smoother surface for colour to go over.

Also known as: ridge filling base coat, ridge-filling base, nail ridge filler, smoothing base coat

A ridge filler is a base coat with a job added. Fine mineral particles, usually silica or talc, are suspended in the film. As the coat dries the particles settle into the low points of the nail plate, so the surface levels out before colour goes on¹. Most ridge fillers are slightly milky or nude, which also softens the colour of the plate.

Vertical ridges, lines that run from cuticle to tip, are common and usually harmless. They come with normal ageing, dry skin or eczema, and sometimes with thyroid or iron problems². A ridge filler hides them under polish. Horizontal grooves, called Beau's lines, have other causes, and a ridge filler will not level a deep one.

Crème finishes show ridges most, because a flat colour reflects every bump. Shimmer and metallic finishes hide them better. A ridge filler under a crème gives the smoothest result. Two thin coats fill more than one thick coat.

Buffing is the other route to a smooth plate, but it thins the nail with each pass. A ridge filler adds a filling layer and leaves the plate intact, so it is the gentler option for nails that are already thin. Nothing coarser than 240 grit is advised for buffing¹.

Written and fact-checked by the India Anaïs editorial team. Every number and rule is linked to its source. How the guides are made.