Quick answer: Use sew-through buttons (the flat kind with 2 or 4 holes) for lightweight fabrics like shirts and blouses. Use shank buttons (which have a loop on the back instead of holes) for thick or structured fabrics like coats and jackets, where the raised shank leaves room for the heavy buttonhole layer to sit underneath.
Sew-through and shank are the two most common button types, and picking the wrong one is the most frequent button mistake. This guide explains the difference, when to use each, and how to attach them correctly.
What is a sew-through button?
A sew-through (flat) button has 2 or 4 holes in the center and is stitched directly through those holes onto the fabric, sitting flat against the surface.
- 2-hole: Simple, common on shirts and lightweight garments.
- 4-hole: Stronger hold, common on heavier shirts and casual wear; allows decorative stitch patterns (parallel, cross, square).
What is a shank button?
A shank button has no visible holes on the front. Instead, it has a small loop — the shank — on the back, which you stitch to the fabric. This raises the button slightly above the surface.
- Self-shank: The loop is molded as part of the button (metal or plastic).
- Thread shank: A shank you create with thread when sewing a flat button onto thick fabric.
Sew-through vs. shank: side-by-side comparison
| Feature | Sew-through (flat) | Shank |
|---|---|---|
| Attachment | Stitched through 2 or 4 holes | Stitched through a back loop |
| Profile | Sits flat against fabric | Raised above fabric |
| Best fabric weight | Light to medium | Medium to heavy |
| Typical garments | Shirts, blouses, light dresses | Coats, jackets, suits |
| Front appearance | Holes and stitches visible | Clean, no visible holes |
| Fastening ease on thick fabric | Can pull and pucker | Easy — leaves room underneath |
When to use sew-through buttons
- Lightweight, thin fabrics (cotton shirts, blouses, linen)
- When you want a flat, classic look
- When decorative stitching is part of the design
- High-volume shirting where machines sew flat buttons quickly
When to use shank buttons
- Thick or structured fabrics (wool coats, denim jackets, suiting)
- When the button needs to stand off the fabric so the buttonhole layer fits beneath it
- Premium or decorative buttons where you don’t want visible holes
- Leather and upholstery, where a clean front is preferred
Rule of thumb: If the fabric is thicker than a few millimeters, choose a shank button — or add a thread shank to a flat button.
How to attach each type
Sewing a flat (sew-through) button
- Mark the button position and thread a needle (double the thread, knot the end).
- Bring the needle up through the fabric and through one hole.
- Stitch across to the opposite hole and back down through the fabric. Repeat 4–6 times.
- For a 4-hole button, repeat for the second pair of holes.
- On thicker fabric, create a thread shank: place a toothpick across the top before stitching, remove it, lift the button, wrap the thread several times around the threads beneath, then knot off.
Sewing a shank button
- Mark the position and thread the needle as above.
- Bring the needle up through the fabric and through the shank loop.
- Pass back down through the fabric. Repeat 6–8 times for a secure hold.
- Knot off underneath the fabric. No thread shank is needed — the button’s own shank provides the lift.
Frequently asked questions
What is the main difference between sew-through and shank buttons?
Sew-through buttons have visible holes and stitch flat to the fabric; shank buttons have a loop on the back that raises the button so thick fabric can fit underneath the buttonhole.
Are shank buttons better than sew-through buttons?
Neither is universally better — they suit different fabrics. Shank buttons work best on thick or structured garments like coats, while sew-through buttons are ideal for lightweight shirts and blouses.
Can I use a flat button on a thick coat?
Yes, but you should add a thread shank — a wrapped column of thread beneath the button — so it sits high enough for the heavy buttonhole layer to close without pulling.
Why do my coat buttons pull and pucker the fabric?
This usually means a flat button was sewn too tightly to thick fabric. Use a shank button or add a thread shank to give the buttonhole layer room.
Which is easier to sew for beginners?
Flat sew-through buttons are the easiest to start with. Shank buttons are also simple since you only stitch through one loop, but require a secure knot to stay put.