A snap button is sewn on just like a regular button, but the two halves come apart

A snap button (also called a press stud) has two metal pieces that click together—a ball side and a socket side. You sew each half to opposite sides of fabric so they meet and hold when pressed. The process takes about five minutes per snap and uses the same basic hand-sewing technique as a regular button, except you'll do it twice: once for each half.

The snap halves are usually attached to a small metal or plastic shank (a post underneath). You push the needle through the holes in that shank and through your fabric, then back up again, repeating until the snap is find. The key difference from a regular button is that snaps need to be aligned perfectly so the two halves meet in the middle when the fabric is folded or pressed together.

Key Takeaways

  • Mark the snap positions on both sides of your fabric before you start sewing, using a pen or tailor's chalk so the halves will align when pressed together.
  • Thread a needle with thread that matches your fabric, knot the end, and push up through the fabric from the underside so the knot stays hidden.
  • Sew through each hole in the snap shank four to six times, going down through the hole and back up through the fabric, then move to the next hole.
  • Finish by wrapping thread around the stitches under the snap to create a thread shank, then knot off on the underside of the fabric.
  • Test the snap by pressing the two halves together; if they don't click or align, you may need to reposition one half slightly and re-sew it.

What you need before you start

Gather a needle, thread, scissors, and the snap buttons themselves. The needle should be small enough to pass through the holes in the snap shank without bending—a size 7 or 8 needle works for most snaps. Thread should match your fabric color or be neutral (black or white works on most garments).

You'll also want a pen or tailor's chalk to mark where each snap goes. If you're working on a thick fabric like denim or canvas, a thimble on your middle finger will protect it from the needle. A small ruler or measuring tape helps you space snaps evenly if you're sewing more than one.

Mark the snap positions on both fabric pieces

Before threading the needle, decide where the snaps will sit. On a shirt or jacket, snaps usually go down the center front, spaced about 3 to 4 inches apart. On a pocket or flap, one snap goes on the flap and one on the garment underneath.

Use a pen or tailor's chalk to mark a small dot on the right side of the fabric where the ball half will go, and another dot on the underside or opposite piece where the socket half will go. The two dots should line up vertically so that when you fold or press the fabric, the snaps meet in the middle. If you're unsure about spacing, lay the garment flat, fold it as it will be worn, and mark through both layers at once.

Thread the needle and sew the first snap half

Cut about 18 inches of thread and pull it through the needle eye. Tie a knot at one end. Push the needle up through the fabric from the underside at your marked dot, so the knot stays hidden underneath. The thread should come out right where you want the snap to sit.

Place the snap ball half on top of the fabric with the shank facing down. Push the needle down through one of the holes in the shank, then back up through the fabric right next to it. Pull the thread snug but not so tight that you pucker the fabric. Repeat this motion—down through the hole, up through the fabric—four to six times, moving around the shank to hit each hole. After the last stitch, bring the needle up underneath the snap shank (between the shank and the fabric) and wrap the thread around the stitches three or four times to create a small thread shank. This gives the snap room to move slightly and makes it less likely to break. Knot off on the underside of the fabric and trim the thread.

Sew the second snap half to the opposite fabric piece

Thread the needle again with a fresh length of thread and knot the end. Push the needle up through the fabric at the second marked dot (where the socket half will go). Place the socket half on top with the shank facing down, and repeat the same sewing process: down through each hole, up through the fabric, four to six times around the shank.

Wrap the thread around the stitches underneath to create a thread shank, then knot off on the underside. Trim the thread. If you're sewing multiple snaps, repeat this process for each pair, always sewing the ball half to one side and the socket half to the other.

Test the snap and adjust if needed

Press the two fabric pieces together so the snap halves meet. You should hear and feel a small click as they lock. If the snap doesn't click or the two halves don't align, the socket half may be slightly off. You can carefully cut the stitches on the misaligned half, reposition it slightly, and sew it again.

If a snap feels loose after sewing, it may not have enough stitches. You can add two or three more stitches through the same holes to tighten it. If the snap is pulling the fabric or creating a pucker, you may have pulled the thread too tight while sewing—this is usually only a problem on very delicate fabrics, and loosening future stitches slightly will help.

Frequently Asked Questions

Can I sew a snap on by machine instead of by hand?

Most home sewing machines cannot sew snaps on because the shank gets in the way of the presser foot. Industrial machines and some specialty machines can do it, but hand sewing is the standard method for home sewers. It takes only a few minutes per snap and gives you more control over tension.

What if the snap keeps coming undone?

The snap itself may be worn out or low-quality, or the stitches may not be tight enough. Try sewing through each hole six to eight times instead of four, and make sure you're wrapping thread around the shank underneath to create a thread shank. If the snap still fails, replace it with a new one.

Do I need to use a specific thread color?

Thread that matches your fabric is least visible, but any neutral color (black, white, gray) works fine on most garments. Avoid thread colors that contrast sharply with your fabric unless you want the stitches to show. The thread color doesn't affect how the snap works.

How far apart should snaps be spaced?

On a shirt or jacket front, space snaps 3 to 4 inches apart. On a smaller item like a pocket or baby garment, 2 to 3 inches works better. The spacing depends on how much stress the snaps will take—closer spacing means each snap carries less load. Look at similar garments for reference if you're unsure.

Can I sew a snap over an existing button hole?

Yes, but you'll need to reinforce the area first. Sew a small patch of interfacing or extra fabric behind the button hole on the underside so the snap shank has something solid to anchor to. Without reinforcement, the snap may tear through the hole and come loose.