What SSK means and why you use it
SSK stands for slip, slip, knit — a technique that decreases one stitch by leaning it to the left instead of the right. You slip two stitches one at a time, then knit them together through the back loop. The result is a left-leaning decrease that mirrors the right-leaning decrease you get from knitting two stitches together (K2tog).
Knitting patterns use SSK and K2tog as a pair because they lean in opposite directions. When you decrease on both sides of a piece — say, on a sleeve cap or the sides of a sweater — using SSK on the left side and K2tog on the right side creates a balanced, symmetrical look. Without SSK, both decreases would slant the same way, and your shaping would look lopsided.
SSK is also gentler on yarn than K2tog because you're not pulling two loops through a single stitch opening. If you're working with delicate yarn or a lacy pattern where the decrease itself is meant to show, SSK gives you a cleaner line.
Key Takeaways
- SSK is a left-leaning decrease made by slipping two stitches, then knitting them together through the back loop.
- You use SSK on the left side of a piece and K2tog on the right side to create balanced, symmetrical shaping.
- The technique works the same on knit rows and purl rows, though the setup looks different.
- SSK is easier to tension correctly than K2tog and puts less strain on delicate yarn.
The step-by-step motion on a knit row
Start with your working yarn in the back and your needles in the standard knitting position — left needle holding the stitches, right needle ready to work. Insert your right needle through the first stitch on the left needle from left to right, as if you were going to knit it. Slip that stitch onto the right needle without knitting it.
Repeat: insert your right needle through the next stitch on the left needle from left to right, and slip it onto the right needle. You now have two slipped stitches on your right needle, sitting in the same direction they were on the left needle.
Insert your left needle through both slipped stitches from left to right — you're going in through the front of the loops. Wrap your working yarn around the right needle and pull it through both loops at once. You've now knitted two stitches together through the back loop, and the result leans to the left.
How to do SSK on a purl row
The principle is the same, but the needle direction changes because you're purling instead of knitting. Insert your right needle through the first stitch on the left needle from right to left (the purl direction), and slip it onto the right needle. Slip the next stitch the same way.
Now insert your left needle through both slipped stitches from right to left — again, the purl direction. Wrap your yarn and purl through both loops. The decrease still leans left, even though you're working on the back side of the fabric.
Many knitters find purl-side SSK harder to see and harder to tension evenly. If your pattern calls for SSK on a purl row and you're struggling, you can work the row in stockinette (knit the right side, purl the wrong side) and do your decreases only on the knit rows. This changes the row count slightly, so check your stitch count against the pattern to make sure you're still on track.
Common mistakes and how to fix them
The most common error is slipping the stitches in the wrong direction. If you slip them knitwise (left to right), they twist as they sit on the needle, and when you knit through the back loop, you're actually working into a twisted stitch. The decrease still works, but it looks tighter and less even than it should. Always slip both stitches purlwise (right to left) — this keeps them untwisted and ready to work.
Another frequent problem is pulling too tight on the first stitch after the decrease. SSK uses two stitches to make one, so there's less yarn in that area than in the stitches around it. If you yank the working yarn hard on the next stitch, you'll create a visible hole or a puckered line. Tension the stitch after the decrease the same way you tension any other stitch — firmly enough that it doesn't slip, but not so hard that it distorts the fabric.
If your SSK decreases look uneven compared to your K2tog decreases, the problem is usually tension rather than technique. SSK and K2tog should look like mirror images of each other. If one is loose and one is tight, adjust your tension on the stitch after each decrease until they match.
When to use SSK instead of other decreases
Use SSK when your pattern specifically calls for it, or when you're decreasing on the left side of a piece and want the decrease to lean left. On the right side of a piece, K2tog (knit two together) is the standard choice because it leans right. Together, they create the balanced look most patterns expect.
If your pattern calls for a centered decrease — one that doesn't lean either direction — you'll use a different technique like slip 1, knit 2 together, pass slipped stitch over (skp) or slip 2 together, knit 1, pass slipped stitches over (sk2p). These are less common but appear in lace patterns and some shaping.
For most everyday knitting — sweaters, scarves, hats — you'll use SSK and K2tog as a pair and won't need to think about other decreases. Once you're comfortable with both, you can recognize which one a pattern is asking for just by reading the abbreviation.
Practicing SSK until it feels natural
The best way to get comfortable with SSK is to practice it on a swatch in a yarn you like working with. Cast on 20 stitches in a worsted-weight yarn and knit a few rows in stockinette. On the next row, place a marker, knit 5 stitches, do an SSK, knit to the end. On the next row, purl across. Repeat this every other row for several rows, and you'll see the decreases stacking up in a neat column.
Once the motion feels automatic on a knit row, practice it on a purl row the same way. Many knitters find purl-side SSK awkward at first because the needle angles feel less natural. Practicing on a swatch means you're not racing against a important date or worrying about messing up a project.
After a few swatches, SSK becomes as automatic as knitting itself. You'll stop thinking about the individual steps and just feel the motion. At that point, you're ready to use it confidently in any pattern.
Frequently Asked Questions
Is SSK the same as K2tog?
No. Both decrease one stitch, but they lean in opposite directions. K2tog leans right; SSK leans left. In most patterns, you use them as a pair on opposite sides of the piece to create balanced shaping. Using K2tog on both sides would make your decreases all lean the same way and look unbalanced.
What if I can't get SSK to look as neat as K2tog?
The problem is usually tension on the stitch after the decrease, not the technique itself. After you complete an SSK, the next stitch you work should be tensioned the same way as any other stitch — not pulled tight. If your SSK still looks loose, try slipping the stitches a little more snugly, but don't twist them.
Can I use SSK on every decrease, or do I have to alternate with K2tog?
You can use SSK for every decrease if your pattern calls for it, but most patterns ask you to use SSK on one side and K2tog on the other. This creates a symmetrical look. If your pattern doesn't specify which decrease to use, you can choose, but balanced shaping usually looks better than all decreases leaning the same direction.
Do I slip the stitches knitwise or purlwise?
Always slip them purlwise — right to left — even on a knit row. Slipping knitwise twists the stitches, and when you knit through the back loop, you're working into a twisted stitch. This makes the decrease look tighter and less even. Purlwise slipping keeps the stitches untwisted and ready to work.