4B Hair: A Complete Guide

Type 4B hair does not coil. Where 4A forms small round spirals, a 4B strand bends in sharp angles, like the letter Z. The effect is a soft, full, cotton-like texture with less visible pattern and a great deal of body. It is among the most versatile hair types for styling, and among the most easily damaged by rough handling.

How to recognize it

• Sharp, angular bends instead of rounded coils. Stretch a strand and release it: it folds, where a coil would spring.
• A fluffy, cottony feel.
• Less visible definition than 4A, wet or dry.
• Shrinkage of around 70 percent.
• Fine to medium strands that break under tension.

Hair with small, clear S-shaped coils is 4A. An even tighter pattern with almost no visible definition is 4C. The line between 4B and 4C is fine, and plenty of people have both.

What 4B hair needs

Each angle in a 4B strand is a point of stress. There are a great many of them, so the hair is fragile, and the same bends stop oil reaching the lengths. The routine has three aims: keep moisture in, handle the hair as little as possible, and give it a pattern by setting it, since it will not form defined coils unaided.

The routine

Cleanse

Weekly, with a gentle shampoo on the scalp. Wash in sections, in loose twists if your hair tangles easily, so it does not mat under the water.

Condition and detangle

Work in six to eight sections. Saturate each with a thick conditioner. Separate tangles with your fingers first, then use a flexible detangling brush or wide-tooth comb from the ends upward. Twist each section when finished.

Deep condition, every wash

Thirty minutes under a shower cap, with a warm towel around it if you can.

Moisturize and seal

On damp hair, section by section: leave-in, then cream, then a little oil on the ends to slow moisture loss.

Styling: set the pattern

A wash-and-go is possible on 4B hair and takes a lot of gel and patience. Most people get better definition, with less effort, from styles that set a shape.

Twist-out. Two-strand twist damp, moisturized hair in medium sections. Let it dry fully, then unravel and separate. Gives defined, stretched waves and coils.

Braid-out. The same idea with braids, for a tighter, crimped pattern and more stretch.

Bantu knots. Small coiled knots that give springy, spiral curls when released.

Flat twists and protective styles. Low-manipulation styles that can stay in for one to two weeks.

The rule for all of them: do not take the style down until the hair is completely dry, or it will frizz.

4B hair does not form a curl on its own. Give it a shape to dry in, and it will hold that shape for days.

Common 4B problems

Breakage. Usually from detangling dry or too quickly, or from tight styles. Slow down, add more conditioner, and loosen the tension at the hairline.

Dryness that returns in a day. Seal with oil after your cream, and re-moisturize midweek with water and a little leave-in. See Hair Porosity, Explained.

Tangles and matting. Keep the hair stretched in twists or braids between styles, and never let it dry loose after washing.

No definition. Set it. Twist-outs and braid-outs do what gel alone cannot.

Hair that seems not to grow. It is growing, and breaking at the ends. Retaining length is the subject of our 4C guide, and the same principles apply.

What to avoid

• Detangling dry hair.
• Fine-tooth combs and stiff brushes.
• Sulfate shampoos every week.
• Unraveling a set before it is dry.
• Tight braids and ponytails.
• Uncovered hair at night.

At night

Re-twist loosely in large sections and cover with a bonnet or scarf. It preserves the style and keeps the hair stretched.

More options are in How to Sleep With Curly Hair.

For the wider family, see the Coily hair guide.