Fitting: back drag lines on trousers

Sewing a perfectly fitting pair of trousers is a way bigger challenge than sewing a well-fitting skirt. Luckily, you only need to study your body features and how to adjust patterns to fit them once, and – voila – every new pair of trousers you sew will fit you well!

One of our customers messaged us with a fitting issue, “I’ve made the Maria trousers out of the heavy jersey. There are diagonal drag lines under the butt that are pointing to the hips. I see this issue in all of my trousers. Either I do something wrong when I sew, or there’s a body feature that makes it look this way…”

In the photo we can see several fitting problems:

1. Under the butt, there are diagonal drag lines pointing to the side seams.
2. In the front, there are drag lines radiating upwards from the inseam.
3. The upper edge of the waistband is at an angle to the center front.

The fitting issues, in this case, come from individual body features, such as a full tummy and the shape and location of the buttocks. Nevertheless, these issues can be easily solved.

What can you do?

On the front leg:

1. Raise the upper edge of the front trouser leg, pocket, and pocket facing by 0.5 cm (1/4”). Draw a smooth line that will be your new front upper edge.
2. Move the front crotch line 0.5–1 cm (1/4–3/8”) towards the side edge and drop it by the same number you drop the back crotch line.

On the back leg:

1. Raise the upper edge by 0.5 cm (1/4”) at the side seam and smoothly taper it towards the center back seam.
2. Drop the back crotch edge by the size of the back drag line. When you do the fitting, pin the fold and measure its width – this is the number you need to deepen the back crotch.
3. Make your trousers wider at the inseam level. To do this, move the upper section of the inseam 1–1.5 cm (3/8–5/8”) outwards and draw the new inseam line.

Make a new trouser toile using your modified pattern. You can check the article “How to transfer pattern markings onto fabric” for some help. If the alterations were done right, you’re ready to sew trousers using your main fabric!

Take a look at more ways to adjust patterns:

Trouser fitting issues: horizontal and vertical drag lines

Flat seat pattern adjustment