Mastering Mattress Stitch

Proper finishing is the key to beautiful knitted garments, and working a perfect mattress stitch is and important skill. In the Spring 2002 issue of Interweave Knits, technical editor Charlotte Morris authored a wonderful article about seaming knitted garments.

Mattress stitch on stockinette fabric
Mattress stitch on garter fabric

Properly worked, a seam should blend in with the garment’s stitch pattern, without stretching or puckering. It should be strong and durable with minimal bulk. Here’s how you can become a mattress stitcher extraordinaire.

Mattress Stitch Seam

To begin mattress seaming, work seams upward from the lower (cast-on) edge. Work the first part of the seam with the tail leftover from the cast-on row. Doing so will eliminate one end to weave in later and will help make a smooth seam join. If the tail left from the cast-on row is not long enough to work the seam, join a length of yarn about twice as long as the length to be sewn. Do not make a knot or tie ends; instead, leave a few inches of the seaming yarn hanging—when the seam is sewn, go back and tighten the end, then work the tail into the seam. Begin by catching the cast-on stitch on each piece.

If the cast-on loops are difficult to see, begin with the first row you can see clearly, and the corresponding one on the other side, then when the seam is established, go back and work the first part of the seam.

Mattress stitch, worked with a tapestry needle and with the right side of the knitting facing, is aptly called an invisible seam. Because it is worked from the right side, this is the best method for matching stitches from one side of the seam to the other. When worked correctly, the rows of stitches line up beautifully without distortion and the seaming yarn is concealed in the seam. Ideally, the two pieces to be seamed should have the same number of rows. If one piece is a row longer, begin and end the seam on the longer piece. This type of seam can be blocked flat.

At the end of a seam, secure the working yarn by darning it into the wrong side of the seam for a few inches. Do not tie a knot. If, despite efforts for perfect matching, there is a slight displacement between the two pieces at the end of the seam, take another stitch back through the top of the lower side to even them out.

Stockinette Stitch: Working with the right sides of the knitting facing you, use the threaded needle to pick up one bar between the first two stitches on one piece (Figure 1), then the corresponding bar plus the bar above it on the other piece (Figure 2). *Pick up the next two bars on the first piece, then the next two bars on the other (Figure 3). Repeat from * to the end of the seam, finishing by picking up the last bar (or pair of bars) at the top of the first piece. To reduce bulk, pick up the bars in the center of the edge stitches instead of between the last two stitches. To prevent a half-row displacement at the seam, be sure to start the seam by picking up just one bar on the first side, then alternate two bars on each side.

Mattress Stitch on Stockinette Fabric

Garter Stitch:

Working with the right sides of the knitting facing, use the threaded tapestry needle to pick up the lower purl bar between the last two stitches on one piece (Figure 1), then the upper purl bar from the stitch next to the edge stitch on same row on the other piece (Figure 2). To reduce bulk, work into the upper bar from the edge stitch (Figure 3) instead of the second-to-last stitch, but keep in mind that the seam will be less firm.

Mattress Stitch on Garter Fabric

Here are some tips for working mattress stitch:

For a smooth, even seam without puckers, take care to alternate row for row from one side of the seam to the other, taking stitches of even lengths on each side.
Work along the same column of stitches, being careful not to stray to one side or the other.
Do not pull the seaming yarn too tight. Doing so will cause the seam to gather, alter the length of the seam, and distort the garment.
Take care not to split the yarn of knitted stitches as you sew (or crochet). Doing so may weaken the yarn and will make the seam look sloppy.

—Charlotte Morris, Interweave Knits Spring 2002

Once you get the hang of it, you’ll be a master mattress stitcher.

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P.S. What’s your favorite seaming technique? Leave a comment and let us know!


Finishing & Construction
Kathleen Cubley

About Kathleen Cubley

Hello daily knitters! I'm the editor of Knitting Daily. I've been obsessed with knitting for about ten years now and my favorite projects are sweaters. I like the occasional smaller project, but there's nothing like yards of stockinette with a well-placed cable or a subtle stitch pattern here and there. I crochet a bit now and then—especially when I need to produce a baby blanket in time for the baby shower. I've been in publishing for 20 years and I'm finally exactly where I want to be: at the crossroads of knitting and communication. I live in Spokane, Washington and when I'm not knitting I enjoy gardening, snuggling with my dogs, swimming, reading, and playing in the snow in the winter. But, really, I'm pretty much always knitting!

4 thoughts on “Mastering Mattress Stitch

  1. Hi, Kathryn.

    Your description of mattress stitch for stockinette contained several disjunctures with the accompanying diagram, alas.

    First, you say to pick up the bar between the first and second stitches; the diagram show picking up the bar within the first stitch.

    Second, you say to pick up the next two bars on each side; the diagram shows inserting the needle into the same place as the yarn came out of the last time, i.e. the next two picked-up bars include the last bar of the last pick-up.

    These small things make all the difference in the world to how the results look!

    Nancy Spies

  2. Kathleen did not write the article!! The article is written by Charlotte Morris. I have finished many sweaters using the above technique, and the above technique is described in many knitting books. Judy in SE WI

  3. I wonder if you can help me. I knitted a sweater for my Husband in Icelandic wool but find it very difficult to put together. The wool I knitted the sweater with just seems to fray and not keep the seams together. I was wondering if I should put it together with thread or would this damage the sweater.
    I like the technique you show of the mattress stich and wonder it this would solve my problem, but with a different type of wool.