Beginner · 2–3 hours · 8 steps
How to sew a pyjama trousers
Pyjama trousers are the quickest wearable garment there is — two seams, a casing and a hem. Because they're loose, the fit forgives almost everything, which makes them the ideal project for learning the crotch seam.
How it's constructed
- Silhouette
- Straight, roomy leg, full length or shorts
- Shaping
- Front and back crotch curves only
- Waist
- Folded casing with elastic, drawstring, or both
- Pockets
- Optional in-seam pockets
- Hem
- Double-turned hem
Fabrics that work
- Cotton flannel for winter pyjamas
- Cotton poplin or lawn for summer
- Double gauze for the softest possible version
What you'll need
- 25–40 mm flat elastic, or cord for a drawstring
- A bodkin or safety pin
- Matching thread
The steps, in order
- 01
Pick your size by hip measurement
With an elastic waist, the hip is the measurement that decides fit. Measure the fullest part and choose from that.
- 02
Cut two fronts and two backs
Back pieces are wider with a deeper curve. Mark front and back straight away — mixing them up is the most common pyjama mistake.
- 03
Add in-seam pockets if you want them
Stitch pocket bags to the side seam allowances before the side seams go together, then press them towards the front.
- 04
Sew the inseams
Join each front to its matching back along the inside leg. Finish the allowances and press.
- 05
Sew the side seams
Join the outer leg seams, catching any pocket bags. Press and finish the edges.
- 06
Join the legs at the crotch
Turn one leg right side out and slip it inside the other, right sides together, matching the curve. Stitch it in one pass, then stitch a second reinforcing line — this seam takes all the strain.
- 07
Make the waist casing
Fold the waist edge down twice, slightly wider than your elastic, and topstitch close to the fold leaving a 5 cm gap at centre back. Add two small buttonholes at the front first if you want a drawstring.
- 08
Thread the elastic and hem
Feed the elastic through, try them on, overlap 2 cm and stitch. Close the gap, add vertical stitches through the casing so the elastic can't twist, then hem both legs to your length.
Mistakes worth avoiding
Sewing the crotch seam before the leg seams
The curve becomes almost impossible to feed through the machine evenly.
Mixing up front and back pieces
The deeper curve ends up at the front and the trousers pull uncomfortably when you sit.
Cutting the elastic to the fabric width
Cut it to your relaxed waist instead, or the waistband won't hold anything up.
Techniques used in this project
Each one is explained on its own page, step by step.
Want this plan for your measurements?
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