Understitching facings and linings

Understitching sews the seam allowance to the facing, close to the seam, so the facing rolls to the inside and doesn't peek out.

Improver15 minutes

ResearchedSewSift editorialChecked 1 Nov 2026

Pinny's tip
Grade the seam allowances before understitching: trim the facing's allowance narrower than the main fabric's.

What you'll need

Iron: press the allowance towards the facing first.
Edgestitch foot (optional): to stay close to the seam.

Step by step

Sew the facing to the garment, trim and clip the seam allowance.
Press the facing and the seam allowance away from the garment.
From the right side, stitch on the facing about 2 to 3mm from the seam, catching the allowance underneath.
Turn the facing inside and press. The seam rolls just to the inside.

Watch

How to Understitch a Facing (1:38)
By Threads Sewing · Open on YouTube

The video this technique page has always pointed to, a 1-minute one from Threads Sewing. Embedded from YouTube with credit; we don't host it. It only loads when you press play.

Common mistakes

Stitching on the garment side. It must go on the facing or lining.
Skipping the clipping. The facing pulls and puckers.
Not pressing first. The allowance slips out from under the stitching.

Watch it done

How to Understitch a Facing by Threads Sewing on YouTube. Opens on YouTube; the video belongs to its creator.
How to Sew an Understitch for a Facing or Lining - Updated by Professor Pincushion on YouTube. Opens on YouTube; the video belongs to its creator.
WHAT IS UNDERSTITCHING? Why you don’t want to skip this crucial sewing step (esp. for pro finishes)! by Evelyn Wood on YouTube. Opens on YouTube; the video belongs to its creator.

Sources

All checked 1 November 2026. We read these; we did not test the products ourselves.