Tapered pull-on trousers are the smart version of the elastic-waist trouser: a relaxed hip, a leg that narrows from the knee to a 36 to 40 cm (14 to 16 in) hem, and a flat elastic waist with no zip, fly or buttons. You sew the in-seam pockets, the side seams and inseams, join the legs along the crotch curve, fold a casing for the elastic and turn up a 3 cm (1 1/4 in) hem. In a cotton twill or a Tencel twill, the project takes four to five hours.

The pattern pieces for size EU 38 / US 6, drawn by Sewly's drafting engine (seam allowances included). Pull-on trousers →

What do you need to sew tapered trousers?

The pieces:

  • Front leg, a mirrored pair, with the casing extension above the waist.
  • Back leg, a mirrored pair, with a longer and more scooped crotch curve than the front.
  • Pocket bags, four pieces, from the main fabric or a lightweight cotton.
  • Elastic, 3 to 4 cm (1 1/4 to 1 1/2 in) wide woven elastic, cut to your waist minus 5 to 7 cm (2 to 2 3/4 in).

Full-length tapered trousers in a women's medium take about 1.8 m (2 yd) of 140 cm (55 in) wide fabric; a men's large takes 2.1 m (2 1/4 yd). The narrow leg lets the pieces nest front against back, so tapered trousers use less fabric than a wide leg of the same length. Add a universal needle in 80/12 or 90/14, polyester thread and a safety pin.

Which fabric suits a tapered leg?

A tapered leg needs fabric with enough body to hold its line down the shin without clinging. Cotton twill at 220 to 280 g/m² (6 1/2 to 8 oz/yd²), a Tencel or viscose twill, a linen-cotton blend or a lightweight wool flannel all work. Very drapey fabrics, such as viscose challis, collapse against the leg and show every fold; save them for a wide leg. Firm canvas is too stiff to gather under an elastic waist.

Pre-wash and tumble dry cotton twill, which shrinks along the length. If you are choosing between fabrics, the trouser fabrics comparison lines them up by weight, drape and crease recovery.

How do you get the elastic waist to lie flat on trousers?

The flat look comes from three things. First, a waist that is not cut much wider than it needs to be: the casing only has to pass over the hips, so the gathers are limited to the difference between hip plus ease and waist. Second, a wide elastic, 3 to 4 cm, which gathers in fewer and shallower ripples than a 2 cm (3/4 in) one. Third, stitching through the elastic at the side seams and center back after it is threaded, so it cannot roll.

Cut the elastic shorter than your waist by 5 to 7 cm for a woven elastic. Pin the loop around your waist and sit down in it before sewing the ends: it should hold the trousers up without leaving a mark. The elastic waistband casing guide covers the fold, the gap and the final stitching.

How do you sew tapered pull-on trousers, step by step?

Seam allowances are 1.5 cm (5/8 in) on a woven. Use a straight stitch at 2.5 mm, and finish the allowances with a zigzag, pinking shears or a serger before pressing them open.

  1. Mark and staystitch. Transfer the pocket notches and the knee notch, then staystitch the front and back crotch curves 1.2 cm (1/2 in) from the edge so the bias of the curve cannot stretch.
  2. Sew the pocket bags to the side seam edges of the front and back legs at the notches, right sides together, with a 1 cm (3/8 in) seam so the pocket sits inside the finished seam line. Press the bags out and understitch.
  3. Sew the side seams. Pin a front to a back, right sides together, and sew from the waist to the top pocket notch, around the pocket bag, and from the bottom notch to the hem. Press the seam open above and below the pocket and the bag toward the front.
  4. Sew the inseams from the hem up to the crotch, matching the knee notches. The back inseam is slightly longer; ease it to the front between the crotch and the knee. Press open.
  5. Join the legs. Turn one leg right side out and slide it into the other, right sides together, with the inseams matched. Sew the crotch curve from the front waist to the back waist, then sew the lower curve a second time inside the first. Trim the curve to 1 cm, clip it, and press the upper parts open.
  6. Make the casing. Finish the top edge, fold it to the inside by the elastic width plus 1 cm, press, and stitch close to the fold's lower edge, leaving a 6 cm (2 3/8 in) gap at the center back.
  7. Thread the elastic, overlap the ends by 2 cm (3/4 in), sew a square through the overlap, and close the gap. Even out the gathers and stitch in the ditch of the side seams and the center back seam through the elastic.
  8. Hem. Try the trousers on with the shoes you will wear and mark the length; a tapered leg looks best ending at the ankle bone or a touch above. Press up 1 cm, then 3 cm (1 1/4 in), and stitch by machine or with a blind hem. The hemming guide covers both.
  9. Press the creases, if you want them: fold each leg along the center of the hem and the center of the knee and press a crease from the hem to about 10 cm (4 in) below the crotch on the front, and to the seat on the back.

What are the common mistakes with tapered trousers?

  • Taking the taper too far. A hem under 34 cm (13 1/2 in) will not pass over a heel without a slit or a zip. Measure your foot around the heel and instep before narrowing a pattern.
  • Hemming before trying them on. A tapered leg that is 2 cm too long puddles at the ankle; one that is too short exposes the sock. Mark the hem on the body, standing.
  • Pressing the crotch seam flat all the way down. The lower curve must be pressed to one side, not open, or the seam allowances show through at the seat.
  • Pulling the elastic too tight. Elastic cut 10 cm (4 in) or more short of the waist leaves deep gathers and a red line on the skin.

If the trousers pull across the seat or drag at the front crotch after the first fitting, the post on common trouser fitting problems shows how to read the drag lines before you cut the next pair.

Can the tapered trousers be drafted to your measurements?

Sewly's pull-on trousers pattern drafts the tapered leg from your waist, hip and seated crotch depth, with in-seam or patch pockets, an elastic width you choose from 1 to 5 cm (3/8 to 2 in) and a length from full to ankle to cropped. The guide gives the elastic length and the fabric needed for 110, 140 and 150 cm (45, 55 and 60 in) wide fabric, with a cutting layout that nests the legs. Switch the leg option to wide and the same pattern becomes the linen trousers of summer, with a different fabric and a different press.