Base Coat and Top Coat: What They Are, Can You Skip Them, and When to Apply Them

By Nanny Nails, nail salon in Nakhon Phanom | Updated 28 Sept 2026

You walk into a beauty shop and, next to the nail polish, there is a row of clear bottles that all look the same. One says base coat, another says top coat, and some say they do both. The first questions that come to mind: do I need to buy all of them? Can I just skip straight to the colour? And if I do buy them, which one goes on first? This article covers it all: what base coat and top coat are, how they differ, whether you can skip them, when to apply them, and how the gel base and top coats we use at the salon differ from the bottles you use at home.

The shortest answer first: if you want polish that looks good and lasts, do not skip either one, because they do different jobs. Base coat sits at the bottom against the nail. Top coat sits at the very top, facing the outside world. The colour you picked is in the middle, sandwiched between them. Leave one out and the colour is exposed on that side straight away.

The diagram below is a cross-section of a nail with every layer in place, from the bottom up. The pale pink layer is the natural nail, the thin pale blue clear layer is the base coat, the two red layers are two coats of colour, and the clear glossy layer on top is the top coat. Look at the tip too: every layer wraps over the edge instead of stopping at it.

What is a base coat?

A base coat is the clear liquid you paint on the bare nail as the first layer, before any colour. If you think of painting a house, it is the primer the painter puts on before the real colour. Nobody sees it on the day the house is finished, but it is the reason the paint is not peeling a year later. A base coat does three main jobs.

• It gives the colour something to grip. A bare nail is smooth, slippery and naturally a little oily, so polish painted straight onto it does not hold as well as it should. Base coat works like double-sided tape: one side grips the nail, the other holds the colour, so the polish lasts longer than on a bare nail.
• It stops polish staining the nail. Wearing red polish without a base coat can turn nails yellow. The base coat is a barrier between the pigment and the nail itself, and the darker the shade, the more it matters. We cover this in detail in dark polish turned my nails yellow: the step people skip.
• It smooths the surface. Natural nails have fine ridges and are not perfectly even. Some base coats are made to fill those ridges, so the colour on top goes on more smoothly.

One thin coat of base is enough. A thick layer does not grip any better. It just makes the bottom layer dry slowly, and every layer on top of it dries slowly too.

What is a top coat?

A top coat, sometimes called a clear coat or sealer, is the clear liquid painted as the very last layer over the colour. Think of the lacquer on wooden furniture that makes it shine and takes the scratches instead of the wood. A top coat does three similar jobs.

• Shine. Many colours lose some gloss once they dry. Top coat brings back a juicy shine and makes the colour look richer.
• Protection from chips and scratches. The top coat takes the friction instead of the colour. When your nails rub against keys, plastic bags or a keyboard, the top coat wears first and the colour underneath stays smooth.
• Sealing the tip. Top coat run across the edge of the tip wraps all the layers underneath. Apply top coat across the nail edges to seal the manicure, and from our gel work at the salon, nails that lift at the tip usually were not capped well.

Top coats are not only glossy. There are matte top coats too, which make colour look soft, like velvet. Same colour, different top coat, and the whole hand looks different. Below is a milky white matte set done at our salon.

Compare it with the same kind of shade finished with a glossy top coat and the difference in shine is obvious. Glossy milky white looks fresh and works every day. Matte looks calmer and more understated.

How do base coat and top coat differ?

The two bottles look so alike that many people think they are the same thing. They are made for different jobs. Here is a side-by-side summary.

Can I use top coat as a base coat?

This question usually comes from someone with just one clear bottle at home. You can, but it will not work as well, because the two are formulated differently. Used as the first layer, top coat does not give the colour as much grip as a base coat. Used as the last layer, base coat does not dry as glossy or as hard, so it will not stand up to a day of friction.

Bottles labelled as both base and top coat (2 in 1) are made to work in both positions, so use them as the label says. They suit people who paint their nails now and then and do not want several bottles. One bottle used as both the first and last layer is better than nothing at all.

Can I skip the base coat?

You can, in the sense that the colour will still go on. But you will notice two things. First, the polish comes off more easily, especially in a sheet from the base, because there is no grip layer. Second, with dark shades like red, burgundy, deep brown or black, the nail underneath may be yellow when you take the polish off, and that takes months to grow out.

If you really are going to skip it, a light, sheer or nude shade worn for a day or two for an event is lower risk than a dark shade worn for a week. But when one thin coat of base takes less than a minute and yellow nails take months to grow out, the choice is fairly clear.

Can I skip the top coat?

You can too, but the colour will go dull sooner, the tips will chip sooner, and the surface will scratch more easily, because nothing is taking the wear for it. Some polishes designed with built-in shine may look fine on day one, but after two or three days you will see the difference.

If your budget means buying only one bottle, go by the colours you wear most. If you love dark shades, get the base coat first because it prevents staining. If you prefer light colours but want shine and fewer chips, the top coat helps more. Or pick a 2 in 1 bottle. The best answer is still both layers.

When to apply them: the right order, step by step

The order of base and top coat is simple. What people usually get wrong is the step before and the step after.

1. Prep the nail. File the shape in one direction, gently push back the cuticle without cutting it, wash and dry your hands, then wipe the nail with polish remover to take off any oil. Nail technicians say any trace of oil will cause polish to lift and peel.
2. One thin coat of base. Cover the whole nail, leaving a tiny gap at the cuticle, run it across the edge of the tip, and let it set.
3. First coat of colour. Thin, cap the tip, let it set.
4. Second coat of colour. Thin, cap the tip again. Use thin coats, two at most.
5. One coat of top coat. Cover the whole nail and run it across the edge of the tip.
6. Let it dry properly, then put on hand cream and cuticle oil.

How long to wait between layers depends mainly on the label, usually just a few minutes. The simple rule is that the layer underneath should be set enough not to move when you paint over it. It does not have to be fully dry. If you paint over a layer that is still wet, the brush drags the colour underneath into grooves.

How to hold the brush and paint without streaks, bubbles or flooding the cuticle is in a separate article: streaky, bubbly and chipping fast: 7 mistakes people make painting their own nails.

Does top coat need reapplying?

With regular polish, the top coat wears away gradually as you use your hands. The shine fades first, then the tips start to chip. Reapply top coat every other day. Paint a thin layer straight over the old one and cap the tip again. There is no need for new base or colour.

After two or three top-ups, the layers start to get thick. If it looks thick or lumpy, or the tips are starting to peel, taking it all off and starting fresh looks better than piling on more.

With gel polish there is no top coat to add at home. Once the gel top coat is cured hard, it stays with the colour until the day it comes off.

How are gel base and top coats different from regular polish?

If you have had gel nails done at a salon, the steps look very similar: base, colour, top. But the products are a completely different system from the bottles you use at home.

• They do not air dry. They are cured. Gel base, gel colour and gel top coat only harden under the light of a curing lamp. Ultraviolet light is used to seal gel polish to the nail, so each layer is cured one at a time. At our salon we use a UV lamp.
• You can use your hands straight after curing. No sitting around waiting for polish to dry, and no blanket prints in the morning.
• Some gel top coats leave a tacky layer. After curing, the very top of some top coats feels slightly sticky, and the nail tech wipes it off to reveal the shine. Others are no-wipe and are glossy as soon as they are cured.
• You cannot mix the two systems. Regular base and top coats dry in the air, gel ones harden under a lamp, so using them together does not work the way it should.
• Under-curing puts the whole layer at risk. From what we see at the salon, gel that lifts off in one whole sheet can come from under-curing, from nails so thin the colour has nothing to hold on to, and polish quality plays a part too. Read more in why gel nails lift: the spot where it lifts tells you the cause.

Gel with every layer applied and fully cured gives a juicy high shine like the photos below, and that shine comes mostly from the gel top coat.

Rubber base: a gel base that does more than a base

In the gel world there is another base people ask about a lot: rubber base. It is a gel base that is thicker than a regular one, used to reinforce thin, bendy nails or very short bitten nails so they are thicker and stronger, giving the colour on top more to hold on to. If your nails are so thin that gel keeps lifting, or bitten very short, we recommend reinforcing them before the colour goes on.

We offer two kinds of reinforcement: rubber base, and builder gel, which is harder. How they differ and which suits which nails is in rubber base vs builder gel: what is the difference.

At Nanny Nails, base and top coat come with every set

Whether you pick a soft nude or a deep oxblood red, every set at the salon starts with shaping, pushing the cuticle back first and then trimming the excess skin, a base coat before the colour every time, and a top coat to finish, with every layer cured under a UV lamp. Shaping, base coat and top coat (50 baht) are already included in every price, with nothing added later.

For example, one plain colour at 200 baht plus rubber base at 200 baht comes to 400 baht. See the full menu on our services and prices page. Every set comes with our 7-day care period, so you can get on with life with peace of mind.

What customers say about our plain colour sets

Read all our reviews on the reviews page.

A quick summary before you pick up the bottle

Base coat is the first layer on the bare nail. It helps the colour grip and stops dark shades staining. Top coat is the last layer over the colour. It adds shine, prevents chips and seals the tip. They do different jobs, one cannot fully replace the other, and skipping either leaves the colour exposed on that side. The order is: prep, base, two thin coats of colour, top coat, then a thin extra layer of top coat every other day if you are wearing regular polish.

And for the days you want every layer done, fully cured and glossy for a long time, browse the plain colours and designs our customers pick most in our gallery, then send us the one you like.

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