How to Knit an Afterthought Heel!

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Whether you are a seasoned sock knitter, or a beginner sock knitter, it’s never too late to add a new heel into your sock knitting skill library!

Afterthought heels used to be so intimidating to me! The idea of SNIPPING YOUR KNITTING?!? NO THANK YOU. But then I actually tried it and realized I was being a baby 😂. They’re so easy, and have quickly become one of my go-to heels! Want to try for yourself? Read on!

First, you need a sock tube, so follow the cuff, leg, and foot portion of your pattern. If the pattern already calls for an afterthought heel, lucky you! If your pattern calls for a different heel, then just skip that part. Knit your leg, then go directly to the instructions for the foot and toes.

Once you’ve closed up your toes (or bound off your cuff if you’re knitting toe-up socks), you should have a long tube! Now you need to identify where to place your heel. For me, I simply use my foot measurements. I know that the foot of my sock needs to be 9″ / 8cm long, from the tip of the toe to the back of the heel. The toe of my sock takes up 1.5″ / 4 cm. My heel will also take up 1.5″ / 4cm. This means when I follow the “foot” portion of a pattern, I need to knit for 6″ / 5cm.

1.5″ / 4cm (toes) + 1.5″ / 4cm (heel) + 6″ / 5cm (foot) = 9″ / 8cm total

So I simply measure back 6″ / 5cm from when I started my toe decreases, and that’s where I place my heel!

Take your sock tube and flatten it out. You should have a cuff at one end and a toe at the other end. You should have half your stitches facing up at you, and the other half facing down. Your toe should look like a wedge, with the decrease lines on the sides of the wedge.

A flattened sock tube

Measure back from where you started your toe decreases to determine where to place a marker for your heel placement (use that handy formula above! Again, I measure 6″ / 5cm from when I start my toe decreases). Clip a marker on a stitch in the middle of your tube, on the row you’ve identified as the perfect spot for your heel.


Identify the line of stitches directly below the line of stitches you’ve marked. Select the first stitch at the edge of your tube on that line of stitches directly below your marked line, and with US Size 1 (2.25mm) needles, insert the tip of your needle into the right leg of that first
st. Next insert the needle into the right leg of the second stitch, and then into the right leg of the third stitch. Continue inserting your needle into the right leg of every stitch until you have picked up half the number of your total sts. If you are following one of my patterns, use these numbers!

Kid (S, M, L, XL): 24 (28, 32, 36, 40) stitches.

Now, repeat the same process for the line of stitches on the other side of your marked line. You should have 48 (56, 64, 72, 80) stitches total divided evenly on your needles. If you are working magic loop, slide all your stitches down to the cables.

Now for the fun (but also kinda scary!) part! Remove your marker and pick out a stitch roughly in the middle of your marked line. Tease that stitch up with your tapestry need le and then snip it with your scissors, being very careful not to snip anything else!

Using your tapestry needle, tease out the yarn you’ve snipped from the stitches. Start in the middle where you snipped and go to the end. Then go back to the middle and tease out the stitches to the other end.

You now have a gaping hole in your sock tube, and live stitches on your needles, ready to knit your heel!

The Afterthought Heel is knit in a wedge just like your toes! The below instructions are a basic guide using the stitch counts I listed above!

Rnd 1: K1, ssk, k 18 (22, 26, 30, 34) sts, k2tog, k1, pm, k1, ssk,
k 18 (22, 26, 30, 34) sts, k2tog, k1.
Rnd 2: K.
Repeat rnds 1 and 2, slipping your markers as you come to them, until 16 (20, 24, 28, 32) sts remain. Use Kitchener stitch to graft your heel closed.

NOTE: You can adjust the depth and fit of your heel by working more or less decrease rnds. Try the sock on occasionally as you work your decreases to see how it’s fitting! Stop your decreases when you can easily pinch the fabric closed. You can also adjust the depth by knitting even with no decreases for a few rounds before starting the decreases! I have a high arch, so I typically knit 3 rounds even before beginning my decrease. This gives my heel more depth and a better fit.

And that’s all there is to it! Pictures below so you can see the steps in action! 👇

Identify the line of sts just below your marked st. Insert your knitting needle into the right leg of the first st at the edge of your tube. Then insert it into the right leg of the second st, then the third st, and so on until you have half your total sts picked up.
Now repeat that same process for the line of sts on the other side of your marker!
Now for the exciting (scary!) part! Tease up the st you marked and snip that poor little guy!
Now take your tapestry needle and start unraveling the yarn from that line of sts in between your needles.
Now you’ve got a big ol’ hole in your sock tube! You’ve got live sts on your needles, ready for you to knit the heel!

One comment

  1. I have definitely got to try an afterthought heel!! Thanks for sharing these detailed instructions. I know you can also just knit in waste yarn so you don’t have to cut (shiver) the yarn.

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