Q: What is the difference between a blanket stitch and a buttonhole stitch? I have a feeling the terms are sometimes used synonymously, but they must be different stitches.
—Nayla Morin, via email

A: Threads Senior Technical Editor Carol J. Fresia replies: You’re correct on both counts: They are different stitches, and they are often misidentified. I’m not surprised you’re confused. Most often, a blanket stitch, which is a bit simpler, is misrepresented as a buttonhole stitch. In fact, I have a vintage stitchery encyclopedia that lists the buttonhole stitch in two chapters. In one, it’s shown as a close-set blanket stitch; in the other it’s illustrated accurately as a buttonhole stitch.

The blanket stitch is an embroidery stitch often used as a decorative edging. Each stitch runs along the fabric edge, then curves away from the edge; it is held at the edge by the following stitch. It is typically worked left to right, with the edge to be stitched facing you, or top to bottom, with the edge on the left.

The buttonhole stitch looks similar but it has an extra loop, or purl, along the edge to secure the stitch more firmly and to add thread where a buttonhole receives the most wear. It is usually worked from right to left, with the edge facing away from you.

Lefty stitchers can reverse the directions.

Threads’ seamstress Norma Bucko distinguishes between the stitches by remembering that, in the blanket stitch, the needle point goes down into the fabric from the right side. In the buttonhole stitch, the needle’s point comes up through the fabric from the wrong side.
In most instances, you may replace a blanket with a buttonhole stitch. However, for buttonholes, you need the buttonhole stitch’s purl for a durable edge. Be sure to wax the thread for added strength.