Quick answer: To use a U-shaped hair pin, push the tips into the outer edge of your bun so they scoop a little hair from the bun and a little from your head, then turn the pin toward the center and slide it in. Four to six pins placed around the bun usually hold it all day.
Key takeaways
- U-pins are open, so they hold by tension inside the bun rather than by clamping.
- The scoop is everything: each pin must catch hair from the bun and hair from the base.
- Work around the bun like a clock face for even hold.
- Large single pins can hold a small bun alone; plain pins work in sets.
- U-pins are gentler on fine hair than bobby pins because they do not clamp.
What is a U-shaped hair pin?
A U-shaped hair pin, sometimes called a French pin or bun pin, is an open pin bent into a U or a narrow wave. Unlike a bobby pin, which closes and clamps a few strands, a U-pin slides into a bun or twist and holds because the hair around it pushes against both prongs. That makes it ideal for buns, chignons and French twists, where you want hold without flattening the shape.
Types of U-pins
U-pins come in three broad kinds: small plain pins used in sets, larger single pins designed to hold a bun on their own, and decorative pins with pearls, leaves or other details that double as jewelry.
| Type | Size | Use | Example |
|---|---|---|---|
| Plain U-pins | About 5 cm | Several per bun, discreet | Black U-Shaped Hair Pins, Set of 100 |
| Pearl-topped U-pins | About 6.5 cm | Decorative, used in groups | Pearl U-Shaped Hair Pins, Set of 18 |
| Large bun pins | About 8–15 cm | One pin holds a small bun | Three-Prong Pin (8 cm), Crescent Metal Pin (15 cm) |
| Statement pins | About 9 cm | Event updos | Gold Leaf Pearl Pin |
How to use U-pins in a bun, step by step
This technique works for a classic low bun and for most other updos. The movement is the same every time: insert at the edge, scoop, turn, slide. Practice on one pin until it feels natural, then work around the bun.
- Make the bun. Gather and twist your hair, coil it into a bun and hold it with one hand.
- Hold the pin. Hold the U-pin at the bend, with the prongs pointing away from you.
- Insert at the edge. Push the tips into the outer edge of the bun, pointing outward and slightly down toward the scalp.
- Scoop. Let the tips catch a little hair from the base, close to your head.
- Turn and slide. Rotate the pin so it points toward the center of the bun and push it in until only the bend is visible, or none of it.
- Repeat around the bun. Place pins at roughly 12, 3, 6 and 9 o'clock, then add more where it feels loose.
How many U-pins do you need?
It depends on how much hair is in the bun and how big the pins are. Fine hair in a small bun may need only three or four small pins, while thick hair in a large bun may need six to eight. One large bun pin can hold a small to medium bun on its own if you use the scoop technique.
| Hair | Bun size | Small plain pins |
|---|---|---|
| Fine | Small | 3–4 |
| Medium | Medium | 4–6 |
| Thick | Large | 6–8 |
The one-pin bun
A large U-pin or three-prong pin can hold a bun by itself. Twist your hair, coil it into a bun, then push the pin into the top of the bun pointing down, scoop scalp hair, turn it so it lies flat and push it through the bun. It is fast and looks deliberate, and it works best on medium hair with a bun that is not too heavy.
Using U-pins in a French twist
U-pins are the traditional way to hold a French twist. After rolling the twist, insert pins along the seam from the bottom up, each one scooping hair from the roll and from the flat hair beside it. Pins along the seam keep the roll tight without a clip. If you prefer a clip, see how to do a French twist with a claw clip.
Four U-pin styles to try
Once the scoop-and-turn movement feels natural, the same pins hold many different shapes. These four styles go from everyday to dressy and use only U-pins, with an optional bobby pin or two for loose ends. Start with the low chignon, since it is the easiest to pin evenly.
- Low chignon: coil hair at the nape and pin around the edge; smooth and polished for work.
- High top knot: twist a high ponytail into a bun and pin at four points; good for workouts at home or cleaning days.
- Half-up mini bun: twist only the top section and hold it with two or three pins, or one large pin.
- Braided bun: braid a ponytail, wrap the braid into a bun and pin along the outer edge where the braid ends.
Decorative pins for events
Pearl and leaf pins do the same job as plain pins but also decorate the style. Place them where they will be seen, usually on one side of a low bun or along a French twist, and use plain pins underneath for the real hold. For a full event look, see our wedding guest hair accessories guide.
U-pins vs bobby pins
U-pins and bobby pins do different jobs. U-pins are open and hold buns and twists by tension, so they do not flatten volume. Bobby pins are closed and clamp a few strands flat, which makes them better for securing small sections, flyaways and braids. Many updos use both. Our comparison, Bobby Pins vs Hair Pins, explains when to use each.
Tips for a secure, comfortable bun
- Add texture to clean, slippery hair before twisting.
- Do not scrape the scalp: the scoop should catch hair, not skin.
- Angle pins slightly so they point into the bun, not out of it.
- Keep it loose at the hairline. The American Academy of Dermatology recommends avoiding hairstyles that pull on the hair and switching styles regularly (AAD, updated November 6, 2024).
How to take U-pins out without tangles
Remove U-pins in the reverse order of how they went in. Hold the bun with one hand, pull each pin back along the path it entered rather than straight out, and drop it into a dish so none get lost. Only release the bun once every pin is out, then loosen the twist with your fingers before brushing. Pulling the bun down with pins still in is what causes snags.
- Find the bend of each pin with your fingertips.
- Slide it out at the same angle it went in.
- Count the pins as you go, so you know none are left in.
- Undo the twist gently and finger-comb before brushing.
Common mistakes
- Pushing pins straight in: without the scoop and turn, pins only hold the bun's surface and fall out.
- Using too few pins on a heavy bun: add more around the edge.
- Clustering pins on one side: spread them evenly.
- Using bobby pins only: they can flatten the bun and pinch fine hair.
Frequently asked questions
How do you put in U-shaped hair pins?
Insert the tips at the edge of the bun, scoop a little hair from the base, turn the pin toward the center and slide it in.
Are U-pins better than bobby pins for buns?
For buns, usually yes. U-pins hold by tension without flattening volume; bobby pins are better for small flat sections.
How many U-pins do I need for a bun?
Usually four to six small pins, or one large bun pin for a small bun.
Do U-pins work on fine hair?
Yes. They are often easier on fine hair than bobby pins because they do not clamp.
Why do my U-pins fall out?
They are probably only in the bun. Make sure each pin scoops a little hair from the base before you turn it.
Can you reuse U-pins?
Yes. Straighten any pin that has spread, keep them in a lidded tin, and replace pins whose tips have lost their smooth coating.
Shop hair pins
Find plain, pearl and statement pins in our hair pins collection, and compare every type of clip in Types of Hair Clips. Orders ship within the US for a flat $6.99, or free on orders of $79 or more.
Sources
- American Academy of Dermatology, Hairstyles that pull can lead to hair loss, last updated November 6, 2024.
