Mattress Stitch Seaming
Mattress stitch is the standard invisible vertical seam in knitting. Worked from the right side with a tapestry needle, it joins two pieces of stockinette by picking up the bars between stitches at the edge.
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Method
Lay the two pieces side by side, right side up, edges aligned. Thread a length of project yarn onto a tapestry needle. Pick up the bar between the first and second columns of stitches on the right piece, then the corresponding bar on the left piece. Pull the yarn through to draw the two edges together. Repeat row by row.
Tension
Pull the seam taut every 2–3 rows. Pulled too loose, the seam will gap. Pulled too tight, the seam will pucker. Aim for a seam invisible from one metre away.
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When to use
Joining the side seams of a sweater. Joining sleeves to body. Any vertical seam in stockinette where invisibility matters.
Limitations
Best for stockinette. For garter stitch, use a different seam (matching the bumps row by row). For ribbing, alternate between knit columns and purl columns.
Abbreviation reference
| Abbreviation | Meaning |
|---|---|
| st(s) | stitch(es) |
Tips
- Pull the seam taut every 2–3 rows to maintain consistent tension.
- Use the project yarn for the cleanest match — a contrasting yarn will show.
- Mattress stitch only works on stockinette; for garter, match bumps to bumps row by row.
In depth
Mattress stitch is invisible because it picks up the horizontal bars between stitches rather than the stitches themselves. The seam yarn travels along the channel between the columns, locking the two edges together without disturbing the stitch columns.