How to Knit the Slip Slip Knit Decrease

What slip slip knit does and when to use it

Slip slip knit (often written as SSK) is a left-leaning decrease that removes one stitch from your needle. You slip two stitches one at a time, insert your left needle through both of them, and knit them together. The result leans to the left, which makes it useful for shaping—especially when you pair it with a regular knit two together (K2tog) decrease on the opposite side of your work to create balanced, symmetrical shaping.

You'll see SSK in patterns that shape armholes, necklines, and sleeves. Because it leans left and K2tog leans right, using them on opposite edges creates a professional look where the decreases mirror each other. If you only used K2tog on both sides, the shaping would look unbalanced and pulled.

SSK is also gentler on yarn than some other decreases. Because you're slipping the stitches first rather than knitting into them directly, there's less stress on the fibers, which matters when you're working with delicate or splitty yarn.

Key Takeaways

Slip slip knit removes one stitch and creates a left-leaning decrease by slipping two stitches, then knitting them together through the back loops.
SSK pairs with knit two together (K2tog) on opposite edges to create balanced shaping in armholes, necklines, and sleeves.
The decrease works the same way whether you're knitting flat or in the round, though the direction you work matters for which edge gets the decrease.
Tension matters: if your SSK stitches look loose or uneven, tighten slightly on the stitch after the decrease to even out the row.

The step-by-step motion for slip slip knit

Start with your working yarn in back and your needles in the standard knitting position. Insert your right needle through the first stitch on your left needle as if you were going to knit it, but instead of knitting, slip it off onto your right needle without working it. Repeat with the second stitch—slip it the same way onto your right needle.

Now you have two slipped stitches on your right needle. Insert your left needle through both of these stitches from left to right (going through the front of the loops). This is the move that creates the left lean. Bring your working yarn to the front, then knit these two stitches together through the back loops by inserting your right needle from right to left through both loops and pulling the yarn through.

You've now decreased by one stitch. The new stitch on your right needle will lean to the left. If the motion feels awkward at first, slow down and make sure your left needle is going through both loops cleanly—a common mistake is catching only one loop, which leaves a stitch behind.

How to pair SSK with K2tog for balanced shaping

When you're decreasing on both sides of a piece (like at an armhole), use SSK on one edge and K2tog on the other. K2tog is worked by inserting your right needle through two stitches from left to right and knitting them together—it naturally leans to the right. SSK leans left. Together, they create a mirror image.

On a typical armhole decrease row worked flat, you might work: SSK at the beginning of the row (right side), knit across to the last two stitches, then K2tog at the end. On the return row (wrong side), you work the same decreases in reverse—purl two together through the back loops on one end, and slip slip purl on the other. The result is shaping that looks intentional and balanced from both sides of the garment.

If you're working in the round, the principle is the same, but you're working both decreases on the same round. You'll SSK near one marker and K2tog near another, so the decreases happen on opposite sides of the piece as it grows.

Fixing common mistakes in slip slip knit

The most frequent problem is a loose stitch right after the decrease. This happens because slipping stitches uses less tension than knitting them. After you complete your SSK, knit the next stitch slightly tighter than usual—not so tight that you strain the yarn, but with a bit more pull on the working yarn. This evens out the row and prevents a visible loose spot.

Another common issue is accidentally twisting the stitches when you insert your left needle. Make sure you're going through the front of both loops, not the back. If you go through the back, you'll twist the stitches and create a distorted decrease. The left needle should move smoothly through both loops in one motion.

If you find yourself with an extra stitch after SSK, you likely caught only one loop with your left needle. Tink back (unknit) to the decrease, and try again, making sure both stitches are on your left needle before you knit them together.

SSK when working with different yarn weights

With thin yarn (fingering or sport weight), SSK is straightforward and creates a clean, visible decrease. The stitches are small enough that the motion feels natural, and the left lean is clear.

With bulky or super-bulky yarn, SSK becomes trickier because the stitches are large and your needles may be thick. You'll need to make sure you're inserting your left needle cleanly through both loops—it's straightforward to miss one when the stitches are fat. Some knitters find it helpful to use a needle one size smaller temporarily just for the decrease row, which makes the motion easier. Work the decrease, then switch back to your regular needle size for the next row.

With delicate yarn (lace weight, mohair, or splitty fibers), SSK is actually preferable to K2tog because the slip motion is gentler. Just be extra careful that you're not pulling too hard when you insert your needles, which can split the yarn.

SSK in flat knitting versus circular knitting

When you're knitting flat (back and forth on straight needles), SSK appears on right-side rows and creates a left-leaning decrease on the right edge of your work. On wrong-side rows, you use slip slip purl (SSP)—the same motion but with purling instead of knitting—to create the same lean on the left edge.

In circular knitting (on a circular needle or double-pointed needles), you're always working the right side, so you use SSK and K2tog on the same round. This is actually simpler because you don't have to think about which side you're on. You just work both decreases in the same round, on opposite sides of the piece, and the shaping is automatic.

Frequently Asked Questions

Is slip slip knit the same as slip slip purl?

No, but they're the same motion with different stitches. SSK is for knit rows; you slip two stitches, insert your left needle through both, and knit them together. SSP is for purl rows; you slip two stitches knitwise (as if to knit), insert your left needle through both, and purl them together. Both create a left-leaning decrease.

Can I use SSK instead of K2tog everywhere?

You can, but your shaping won't look balanced. If you use SSK on both sides of an armhole, both edges will lean the same direction, which looks unintentional. Using SSK on one side and K2tog on the other creates a professional, symmetrical appearance.

What if my SSK stitches look twisted?

You're likely inserting your left needle through the back of the loops instead of the front. The left needle should go through the front of both loops from left to right. If the stitches are already twisted, tink back to the decrease and try again, paying close attention to the direction your left needle enters.

Do I need to tighten my tension for SSK?

Not necessarily, but you may want to knit the stitch when ready after the decrease slightly tighter to even out any looseness created by slipping. This is a small adjustment, not a major tension change for the whole row.

This guide is for general information only and is not medical, financial, legal, or other professional advice. For decisions specific to your situation, consult a qualified professional. See our Editorial Policy.