How to Sew Pockets in Side Seams: In-Seam Pocket Tutorial
Side seam pockets are hidden pockets sewn into a side seam. Easy to add to skirts, dresses, and trousers. Step-by-step tutorial.
In-seam side pockets are the hidden pockets you find in well-made skirts, dresses, and trousers. From the outside, you see only a small slit at the side seam; from the inside, two fabric pockets hang invisibly behind the side seam. They are a relatively simple addition that dramatically improves the wearability of any garment with a side seam.
What an in-seam pocket looks like
The construction is simple: two pocket bag pieces, one attached to each side seam edge. The side seam is sewn closed above and below the pocket; the pocket area is left open. The two pocket bags sew together to form a closed pocket reachable through the side seam slit.
When in-seam pockets work well
Skirts (A-line, gathered, fitted), dresses with side seams, classic trousers, long tunics. They work less well with heavy fabric, very fitted garments, or prominent side seam decoration.
What you need
Garment with side seams not yet sewn. Pocket bag fabric: 0.5 m of cotton lawn, broadcloth, or matching garment fabric. Pocket bag pattern piece.
Pocket bag dimensions
A standard pocket bag is about 15 cm wide at the side seam attachment, 22 to 26 cm tall, with a curved bottom for smooth movement.
Step-by-step construction
Step 1: Cut the pocket bags
Cut two pocket bags. They should be mirror images.
Step 2: Attach pocket bags to the side seam edges
Place the pocket bag right side together with the front skirt’s right side, aligning along the side seam edge. Pin where the pocket opening will be (typically 18-22 cm down from the waist). Sew with a 1 cm seam allowance. Repeat for the back skirt.
Step 3: Press pocket bags away from the body
Press each pocket bag toward the inside of the garment.
Step 4: Sew the side seam (with pocket area open)
Place the front and back skirts right sides together. Sew the side seam from the top down to the top of the pocket attachment. Skip the pocket area. Continue from the bottom of the pocket attachment down to the hem.
Step 5: Sew the pocket bags together
With the garment inside-out, pin the two pocket bag pieces together along their outer edges. Sew with a 1 cm seam allowance, going around the curved bottom.
Step 6: Reinforce the pocket opening
Backstitch firmly at the top and bottom of the pocket opening, then bar tack each end.
Step 7: Press the pocket toward the front
This tucks the pocket into the front of the skirt — easier to access and less visible from outside.
Common mistakes
The pockets gape open: adjust placement to 8-12 cm below the waist (the natural drop of the hand).
The pocket bags push the side seam outward: use lightweight cotton lawn instead of heavier fabric.
The pocket opening tears at the corners: re-bartack with more passes.
The pockets feel small: cut them larger (18 by 24 cm or 20 by 26 cm).
Pocket bag fabric choice
| Fabric | Pros | Cons |
|---|---|---|
| Cotton lawn | Lightweight, breathable | Can fray |
| Cotton broadcloth | Sturdy, doesn’t shift | Slightly bulkier |
| Pocketing fabric | Designed for the purpose | Less eco-friendly |
| Matching garment fabric | Visually invisible | Adds bulk |
| Lining fabric | Smooth, slippery | Can fray |
For most purposes, lightweight cotton lawn or broadcloth is the right choice.
Closing thought
In-seam pockets are one of the smallest improvements to a garment that delivers the largest practical benefit. A skirt with pockets is dramatically more useful than the same skirt without.
For the broader intermediate skill set, see our complete intermediate techniques roadmap. For the alternative welt pocket style, see our welt pockets guide.