Undercut

What an undercut is

The sides and back are clipped short, often a grade 1 or 2 (3 to 6mm), all the way up to roughly where the side of the head turns into the top. Then they stop. Everything above that line is left long, typically 8cm or more, and sits over the short hair like a lid.

That hard line is called a disconnect, which is why the cut is often called a disconnected undercut. Strictly, a classic undercut is always disconnected. The longer name just makes the point clearly when you are in the chair.

Lift the top and you can see the line. Let it fall and the long hair covers it, so from some angles an undercut looks like a long cut with tidy sides. Comb the top back or to one side and the contrast shows.

Undercut vs fade

This is the question most people need answered, and the difference is simple.

A fade blends. The sides get gradually shorter towards the bottom, with no visible step anywhere, and the top of the fade merges into the top of the head.

An undercut does not blend. The sides are one length, and there is a clear step where they meet the top.

Some barbers now cut a faded undercut, where the sides are faded from short at the bottom to longer at the top, and then still stop at a hard line under a long top. It looks less stark. It is still an undercut, because the disconnect is still there. If you want a cut with no step at all, you want a fade, and the types of fade page explains the options.

The practical difference shows when it grows out. A fade softens gradually. An undercut grows out into a shelf, because the sides are trying to catch up with a top that is many times longer.

Who an undercut suits

Hair type. Thick hair is the natural fit. The undercut takes the weight off the sides, which is where thick hair causes the most trouble, and leaves plenty on top to style. Straight hair falls cleanly over the line. Wavy hair adds texture to the top. Curly and coily hair work if the top is long enough to fall over the line rather than sit up off it, and a crisp edge helps.

Fine or thinning hair. Usually the wrong choice. Short sides under a long, heavy top draw attention to any thin areas on top, and a long top separates and shows the scalp. A shorter cut serves better, and haircuts for balding men covers the options.

Face shape. Oval and square faces carry it most easily. On a round face, combing the top up and back adds height and helps. On a long face, wearing the top swept to the side rather than straight up avoids adding more length.

Work. Combed neatly, a classic undercut with grade 2 sides passes in most offices. A very short skin-close version with a high contrast is louder. A grade 3 on the sides softens the whole thing.

Avoid it if you want a cut that grows out gracefully. It does not.

How long the top needs to be

This decides what you can do with it.

Short undercut, around 5cm. Enough for a textured top pushed forward or a small quiff. Quick, and the contrast is modest.

Classic undercut, 8 to 15cm. The usual length. Long enough to slick back, sweep to the side or push up into a pompadour. This is the version most people mean.

Long undercut, 15cm and over. Long enough to tie up into a knot at the crown. The sides stay short under it. Growing to this length from scratch takes well over a year, because hair grows about 1cm a month. For longer cuts generally, see medium and long hairstyles.

How to ask a UK barber for an undercut

1. Ask for an undercut, and say disconnected. "A disconnected undercut, one length on the sides, no blending into the top." This stops a barber helpfully fading it.
2. Give the side grade. A grade 1 (3mm) or grade 2 (6mm) is common. A grade 0 (no guard, about 0.5 to 1mm) is harsher. A grade 3 (9mm) is softer and more office-friendly. If you want a faded undercut, say so, and give the bottom and top grades.
3. Show where the line goes. Usually the top of the sides, where the head starts to curve over. Point to it. Too low and the top will not cover it, too high and the top looks like it is perched on.
4. Say what to do with the top. If you are keeping the length, ask for the top trimmed only and say how you wear it, back, to the side or up. A barber cuts a top differently depending on which way it will sit.

Also decide on the back. The undercut can run all the way round, or stop at the crown so there is more length at the back. And say whether you want a natural or squared neckline.

Styling an undercut

An undercut needs styling. The sides look after themselves, but a long top left alone just hangs.

Slicked back. Work a cream or light pomade through damp hair, comb it straight back, and blow-dry it in place for hold. The classic version. Full method on the slick back página.

Side swept. Part it on one side and comb it over. Softer, and better on a long face.

Pompadour. Blow-dry the front up and back with a round brush, then set it with a stronger clay or paste. Takes the longest. The quiff is the shorter, easier cousin.

Textured. Matte clay rubbed through dry hair with your fingers, left slightly messy. Best on wavy hair.

Curly. Curl cream on damp hair, scrunch, and let it dry. Do not brush it once dry.

Most undercut styles take two to five minutes. Start with less product than you think you need.

Upkeep and how often to cut an undercut

Two different timetables.

Sides every two to three weeks. Regrowth on short sides softens the line, and the line is the point. Some barbers will do a sides-only tidy between full cuts.

Top every six to eight weeks, or less often if you are growing it. A trim to take the ends off and keep the shape.

Between cuts, a clipper tidy on the neckline at home buys a few extra days. The line itself is best left to the barber.

Variations and growing it out

• Slicked back. Long top combed back. The classic.
• Side swept. Top swept to one side. Softer.
• Faded undercut. Sides faded rather than one grade, still disconnected at the top. Less stark.
• Undercut with a knot. Top long enough to tie. Sides stay short.
• Hard part undercut. A parting shaved in with a razor or trimmer for a sharper line.

Growing out an undercut is the hard part. With grade 1 sides and a 10cm top, the sides need the best part of a year to catch up. The middle stage is the awkward one, when the sides stick out under the top like a shelf.

The way through is gradual. Let the sides grow, and at each visit ask the barber to blend the bottom of the top into the sides so the step gets smaller. A few months in, it starts to look like an ordinary longer cut.