Smoothing primer

A smoothing primer is a clear or faintly milky gel that goes on after skincare and before foundation. Most are made largely of silicone. The fluid part is usually dimethicone, often with a volatile silicone that evaporates after spreading; the body comes from a silicone elastomer, a crosslinked silicone swollen in silicone oil, which gives the gel its dry, velvety slip. Spread thinly, it leaves a fine film over shallow lines and in the mouths of pores. That is what makers mean when they sell a primer as “blurring” or “pore-minimising”: the skin underneath is unchanged, but its surface is more even, so it catches less light, and foundation glides across it instead of collecting in it. A newer group, sold as silicone-free, aims at the same effect with water gels and fine powders.

It is the plainest of the primers, and the one the others are variations on. A pore-filling balm is the same idea in a firmer, waxier form, pressed into particular pores rather than smoothed over the face. A mattifying primer adds powders that absorb oil and is chosen for shine rather than texture; a hydrating primer is mostly water and is chosen for dryness; an illuminating primer carries pearl. A smoothing primer adds no colour and no glow. Its only job is the surface.

The first decision is how much silicone you want. The classic formulas are silicone through and through, with a dry, powdery slip and a finish that stays velvety all day. Newer “perfecting” primers carry a lighter silicone film in a water gel, and some are made without silicone at all; they feel fresher on the skin, and whether they blur as much is worth testing on your own face. If pores and fine lines are what you notice in the mirror, the heavier gel does more. If your skin is dry, either can sit on flaky patches and make them more obvious, and a hydrating primer, or simply a good moisturiser, will serve you better there.

The second is what goes on top. The usual advice is to match like with like, a silicone primer under a silicone foundation and a water-based one under a water-based formula, and it is a sensible starting point rather than a law. The real test is what happens as you blend. If the foundation rolls into small balls, streaks or refuses to settle, the two layers are working against each other, or there is too much of one of them. A primer and a foundation that both list dimethicone or cyclopentasiloxane near the top usually sit together without trouble.

Some smoothing primers add a sunscreen and are sold on an SPF number. Treat that as the maker’s claim for a layer worn thinly, not as the day’s sun protection.

Let skincare, and any sunscreen, sink in for a few minutes first; silicone smoothed over a wet cream slides about and can pill. Then take a pea-sized amount, less than seems right, and pat it into the places that need it, usually the nose, the centre of the cheeks and the forehead, rather than spreading it over the whole face. Patting and pressing leave the film where it is wanted; rubbing drags it off the pores and rolls it into flakes with whatever is underneath.

Give it a minute to settle while the lighter silicones evaporate and the film sets. Foundation then goes on best pressed or stippled, with a damp sponge or a dense brush, so that it is laid over the primer instead of dragging it away. If the foundation slips, separates or looks greasy by midday, you have used too much primer, not too little.

At night, remember that the film was made to resist water. A cleansing oil or balm, or a second cleanse, removes it more thoroughly than a single wash.

The primer as a product of its own is young, and who sold the first one is disputed. Laura Mercier’s line was launched in 1996, and a fashion site credited it in 2019 with “introducing a pre-makeup priming step to consumers in the first place, back in 1996 when the brand first launched”.^[1] Smashbox, which began as a Los Angeles photo studio in 1990 and became a make-up brand in 1996, launched its Photo Finish primer in 2000; in 2025 the brand’s general manager said that “there really weren’t primers out back in 2000”.^[2] Both accounts come from the brands or from coverage of them, they cannot both be right, and the record does not settle it.

What made the smoothing primer possible was a material. A Dow Corning patent filed in March 1996 and granted in August 1997 describes silicone elastomers swollen into gels and pastes that “spread smoothly on the skin”, names foundations among the make-up they could go into, and promises a “dry, silky-smooth” feel.^[3] The patent says nothing about primers, and nothing here shows that any primer was made from it: the likeness is one of chemistry, not a recorded line of descent. But the velvety slip it describes is the one a smoothing primer still has.

Today the primer also comes in hydrating, mattifying, illuminating and colour-correcting kinds, and in 2025 a search for “primer” on Ulta’s website returned 242 results.^[2] The clear gel is still the one the others are measured against.