Hijab Undercap Guide: Types, Fabrics, Fit & How to Wear One

The hijab undercap is the least glamorous thing you wear and the one that decides how your day goes. The right cap keeps your hijab where you put it and gives even floaty chiffon a neat shape; the wrong one slides back by lunchtime or leaves you with a sore head.

This guide explains the types of undercap (also called an underscarf or hijab cap, bonnet or sous-hijab in French, Unterkopftuch in German), which suits which hijab, how it should fit and how to put it on.

What is a hijab undercap and what does it do?

An undercap is a close-fitting layer of stretch fabric worn directly over your hair, underneath the hijab. It does four jobs at once:

• Grip. A matte cap gives the hijab a textured surface to hold, so smooth fabrics stop sliding.
• Hair coverage. It keeps fringes, baby hairs and the nape tucked away, even when the hijab shifts.
• Opacity. Under semi-sheer chiffon or a light hijab, it stops hair showing through.
• Shape. It creates a smooth base, so the hijab's front edge sits in a clean line around your face.

Undercap, underscarf and hijab cap all mean the same thing in most shops.

Types of hijab undercap compared

Most undercaps fall into five shapes. Choose by the coverage you want and whether you prefer a fixed or adjustable fit.

Tube undercap

A tube undercap is a band of stretch jersey you pull on and push back to the hairline. It is fast and packs flat, but its grip depends entirely on the stretch; once that relaxes with washing it tends to creep back, so it suits grippy jersey hijabs best.

Tie-back undercap

A tie-back undercap looks like a bonnet from the front, with two ties at the nape that knot around your bun. You set the tension yourself, so it fits many head sizes and hair volumes and loosens the moment it feels tight. This is the shape of our Hijab Undercap, Modal: a tie-back cap in soft stretch cotton-modal jersey, one size to fit a head circumference of about 54–60 cm, in 25 colours.

Hijab Undercap, Modal – Sand £8.00 Hijab Undercap, Modal – Black £8.00 Hijab Undercap, Modal – White £8.00 Hijab Undercap, Modal – Navy Blue £8.00

Ninja undercap

A ninja undercap adds a neck panel that covers the throat and the back of the neck, leaving only the face open. It suits loose drapes where the neck might show, and sport, though the extra layer can feel warm on hot days. We do not currently sell a separate ninja cap.

Bonnet and built-in caps

A closed bonnet gives a smooth, rounded shape that suits turban styles. Some hijabs have the cap built in: our turbans include a tie-back bonnet hijab, a stretch cotton cap with a fine rhinestone band at the forehead and long voile tails that tie at the nape, and a pre-tied jersey turban that covers the head from forehead to nape. One-piece and instant hijabs have an integrated inner cap too, so you need nothing underneath.

Tie-Back Bonnet Hijab with Rhinestones – Plum £15.00 Pre-Tied Turban for Women – White £15.00

Which undercap for which hijab fabric and style

Match the cap to the hijab on top. Slippery or sheer fabrics need more from the cap than grippy ones. For the wraps themselves, see our step-by-step hijab styles guide.

Our chiffon hijabs are semi-sheer, so a cap in the same colour stops hair or a dark cap showing through. With satin hijabs, grip matters most: a matte cap and a firmer first wrap beat extra fastenings. If slipping is your main problem, see how to stop your hijab slipping.

Best undercap material and colour

Which fabric?

The best undercap material is soft, stretchy and matte on the outside: it grips the hijab, moves with you and does not press.

• Modal and bamboo modal. Very soft against the skin, breathable and matte, with a gentle grip. A good all-rounder for long days.
• Cotton jersey. Breathable, grippy and easy to wash; choose a stretch knit, as plain cotton loses its shape faster.
• Satin- or silk-lined caps. The smooth lining is gentle on curly or fragile hair, but gives less grip, so it needs a matte outer layer. We do not sell satin-lined caps.
• Lace and mesh. Decorative or airy, but usually less opaque.

Matching or contrast colour?

Under a sheer or light hijab, match the colour: a contrasting cap shows as a band at the forehead. The simplest way to get an exact match is a hijab sold with its own cap: our hijabs with matching undercap include modal, modal chiffon and bamboo modal hijabs, each with a stretch-jersey undercap in the same shade, plus an instant chiffon hijab sewn onto its cap.

Modal Chiffon Hijab with Undercap – Mauve £15.00 Modal Hijab with Undercap – Soft Peach £17.00 Bamboo Modal Hijab with Cap – Dusty Blue £20.00 Instant Chiffon Hijab with Undercap – Taupe £17.00

Under an opaque jersey or modal hijab, a black, white or sand cap works with almost everything, and a thin line of contrast, such as camel under navy, is a quiet style choice.

Fit: how to avoid undercap headaches

A cap that grips hard all day puts steady pressure on the forehead, temples and behind the ears. The fix is almost always fit.

How snug should an undercap be?

Snug enough that it stays put when you nod, loose enough that you forget it is there. A red line on your forehead or an ache at the temples after an hour means it is too tight; if two fingers slide under the band easily, it is too loose.

Common causes and fixes

• Cap too small. Measure around your head just above the eyebrows and ears; our undercap fits about 54–60 cm (see the size guide).
• Ties knotted too hard. Knot a tie-back cap with just enough tension to hold.
• Band on the temples. Place the front edge on your hairline, not low across the forehead.
• A tight, high bun. It pulls on the scalp under the cap. Loosen it and move it lower.
• Glasses squeezed in. Arms trapped under a tight band press behind the ears; wear them between cap and hijab.
• Pins pressing in. Fastenings pushed against the head add pressure points; magnets help.

Give your head a break at home. This is general comfort advice, not medical advice: if headaches continue even with a loose cap, speak to a doctor.

What to wear under a hijab: your hair

What sits under the cap matters too. A low, loose bun or plait at the nape gives the hijab a ledge to rest on; a high, tight bun pulls at the hairline and drags the front back.

• Tie dry hair low and loosely, with a soft scrunchie rather than a hard clip.
• Vary where you tie your hair so the same spot is not under tension every day.
• Let your hair breathe at home, and wash caps often.

Can undercaps cause hair loss? Dermatologists note that tightly pulled-back hair under a covering can contribute to thinning at the hairline, and recommend tying it loosely (see the American Academy of Dermatology's advice on hairstyles that pull). If you notice thinning, see a doctor or dermatologist.

How to wear a hijab undercap, step by step

These steps are for a tie-back undercap like ours; the notes below cover tube and ninja caps.

1. Start with dry hair. Tie it in a low, loose bun or plait at the nape; damp hair shifts as it dries.
2. Place the front edge. Hold the cap by the ties, put it over your head and set the front edge right on your natural hairline.
3. Smooth it back. Run your hands from the forehead to the crown so the fabric lies flat, and tuck any loose hairs at the temples inside.
4. Tie at the nape. Bring the ties around the bun, cross them and knot them just firmly enough to hold. Tuck the ends under.
5. Check the fit. Nod, look down and turn your head. The cap should stay put without pressing. Adjust the knot, not the front edge.
6. Put your hijab on top. Set the hijab edge a few millimetres in front of the cap and fasten the first wrap through both layers, so they move together.

Tube cap: pull it on like a headband, slide it back to the hairline and tuck the back under your bun. Ninja cap: step your face through the opening, settle the neck panel flat, then set the front edge at the hairline.

How to wear a hijab without an undercap

You can absolutely wear a hijab without an undercap. What you need instead is grip and a secure front edge.

• Choose a grippy fabric. Jersey hijabs stretch around the head and hold on bare hair far better than chiffon or satin.
• Go for a built-in cap. Our instant hijabs include a one-piece jersey hijab with an integrated undercap, an instant jersey hijab with an inner cap and crossover band, and an instant amira with a fitted inner cap. Our guide on how to wear an instant hijab shows how to get the fit right.
• Use magnets instead of relying on the cap. A magnet under the chin and one above the ear from our hijab magnets hold the wrap without piercing it.
• Texture your hair. A low plait gives more grip than a smooth bun.

One-Piece Jersey Hijab – Navy £15.00 Instant Jersey Hijab – White £13.00 Instant Amira Hijab XL – White £20.00 Matte Hijab Magnets, 6-Pack – Neutrals with Gold £14.00

Chiffon and satin are the exceptions: without a cap they slip and can show hair, so keep an undercap for those. For hot days, see our best hijab for summer guide; for training, a pull-on sport hijab replaces both layers (see the best sport hijab guide).

Washing your undercaps and building a small kit

Undercaps sit against your skin all day, so wash them more often than your hijabs: after every one or two wears, and after every wear on hot days or after sport. Check the care label first. For ours, that means a cool, gentle machine wash at 30 °C inside a mesh bag, no bleach and no fabric softener, then air-drying flat or over a rail, away from direct heat.

For stains along the band, read how to wash a hijab. A small kit covers almost every outfit:

• Two black undercaps (one on, one in the wash)
• One white and one skin-tone neutral cap
• A hijab with a matching cap for chiffon days
• A set of hijab magnets and a mesh wash bag

FAQ

What is the best undercap for a hijab?

For most people, a tie-back undercap in a soft, matte fabric such as modal or cotton jersey. The ties let you adjust the fit so it holds without pressing. Choose a ninja cap for neck coverage, and a matching colour under chiffon.

Do I need to wear an undercap with a hijab?

No, it is a choice. An undercap helps most with slippery or sheer fabrics such as satin and chiffon. Jersey hijabs and instant hijabs with a built-in cap hold well without one.

Why does my undercap give me a headache?

Usually because it is too tight, sits too low across the temples, or presses a high bun or glasses against your head. Choose the right size, place the front edge on your hairline, tie a tie-back cap loosely and tie your hair low. If headaches continue with a loose cap, speak to a doctor.

What is a ninja undercap?

A ninja undercap is a cap with an attached neck panel, so it covers the head, neck and throat and leaves only the face open. It suits loose drapes and sport.

Is a tube or a tie-back undercap better?

A tube cap is quicker to pull on and suits grippy jersey hijabs. A tie-back cap is adjustable, fits more head sizes and hair lengths, and holds slippery chiffon and satin better, so it is the more versatile choice.

Can an undercap cause hair loss?

A cap worn over hair that is pulled back tightly every day can add to tension at the hairline. Tie your hair loosely and low, avoid caps that squeeze, and give your hair breaks at home. If you notice thinning, see a doctor or dermatologist.

What colour undercap should I wear?

Match the colour under chiffon and other semi-sheer or light hijabs. Under opaque jersey or modal, black, white and a skin-tone neutral work with almost everything, and a contrast colour is a style choice.

How often should I wash my undercap?

After every one or two wears, and after every wear in hot weather or after exercise. Wash it cool and gentle in a mesh bag, skip the softener and the tumble dryer, and follow the care label.

Want to see how every hijab fabric compares? Read our complete hijab fabric guide.