What Is an I-Cord Cast On?
An i-cord cast on creates a neat, rolled, cord-like edge along the bottom of your knitting — the same round, tidy tube as a regular i-cord, but attached directly to the cast-on row of your project. Rather than casting on and knitting your first row in the usual way, you knit a short i-cord and simultaneously pick up stitches from a provisional cast-on edge, joining the cord to the base of the fabric one stitch at a time.
The result is a beautiful, polished edge that looks handmade in the best sense — architectural and clean, adding a decorative detail that elevates the project without requiring additional finishing work. It is particularly beloved for shawls, where the cast-on edge is highly visible and often one of the first things an admirer notices.
I-cord cast ons also work beautifully on: blanket and throw edges, the lower hem of a rectangular yoke cardigan, any project where a decorative trim at the start is wanted, and square or rectangular pieces where all four edges will be finished identically (working an i-cord trim on each edge after the fact).
Understanding How It Works
The i-cord cast on works on a simple principle. You begin with a provisional cast on — a temporary foundation of stitches that will be unraveled later. These stitches represent the number of stitches your project needs.
Separately, you cast on a small number of stitches (usually 3) for the i-cord itself. You then work the i-cord back and forth while at the end of each i-cord row, picking up one stitch from the provisional cast-on and working it together with the last i-cord stitch (k2tog). This joins the cord to the provisional stitches, one at a time, across the entire width of the project.
When you have worked across all provisional stitches, the i-cord is attached along the entire bottom edge, and you have a set of live stitches ready to begin your project in the usual way. The provisional cast-on yarn is then removed, leaving only the attached i-cord and the live stitches above it.
What You Need
- Your main project yarn and needles
- A contrasting waste yarn for the provisional cast on (smooth, similar weight)
- A crochet hook (for the provisional cast on)
Step by Step
Step 1 — Provisional cast on. Using waste yarn and a crochet hook, work a crochet provisional cast on for the total number of stitches your pattern requires. If your pattern starts with 80 stitches, provisionally cast on 80. These stitches will sit on your needle ready to be worked.
Step 2 — Cast on i-cord stitches. At the beginning of the provisional stitches (the right end, if you will be working left to right), use your main yarn to cast on 3 additional stitches using a simple cable cast on or backward loop. These 3 stitches are your i-cord.
You now have 80 + 3 = 83 stitches on the needle. The 3 i-cord stitches are at the right end.
Step 3 — Work the first i-cord row. Knit the 3 i-cord stitches only. Do not touch the 80 provisional stitches yet.
Step 4 — Slide and join. Without turning the work, slide all stitches to the right end of the needle (you are working on double-pointed needles or a circular needle used as a DPN). The yarn is now at the left side of the i-cord stitches. Knit 2 of the i-cord stitches. For the third i-cord stitch, work k2tog — knitting the last i-cord stitch together with the first provisional stitch. One provisional stitch has been incorporated into the cord edge.
Step 5 — Repeat. Continue: slide, knit 2 i-cord stitches, k2tog with the next provisional stitch. Repeat until all provisional stitches have been worked into the cord.
You will work this sequence 80 times (for 80 provisional stitches). Each repeat incorporates one more provisional stitch into the cord edge. After 80 repeats, you have the 3 i-cord stitches remaining plus the attached cord running across the bottom of the project.
Step 6 — Remove waste yarn. Carefully remove the provisional cast-on waste yarn. The stitches that were provisionally cast on are now attached to the i-cord below and will form the live stitches for your project body above.
Step 7 — Begin your project. Place the live stitches back on the needle and begin knitting your project pattern from the first row/round.
Working with Double-Pointed Needles vs. Circular Needles
The i-cord cast on requires that you can slide stitches back and forth along the needle without turning — this is how i-cord is always worked. Double-pointed needles make this most intuitive. If you prefer to use circular needles, use a short circular (40cm or less) and treat it as a flexible DPN, sliding stitches to the right tip when needed.
The key is not to turn the work between i-cord rows. The yarn will always be at the wrong end when you finish each row, but sliding the stitches puts it back in position. This "wrong end" is what creates the i-cord tube.
Troubleshooting
If your i-cord is twisting rather than lying flat, check that you are always working the stitches with the right side of the cord facing you and that you are not accidentally turning the work. The cord should spiral slightly as you work — this is normal — but it should resolve and lie flat when you stretch it gently.
If the join between the cord and the provisional stitches looks loose or gappy, try pulling the yarn slightly more firmly when working the k2tog join. The join stitch should be snug but not tight.
If the cord itself is too loose, try going down half a needle size for the i-cord stitches only, or tension the yarn more firmly as you slide and work.
The Payoff
The i-cord cast on requires more setup than a simple long-tail or cable cast on. It is genuinely slower, especially the first time. But the resulting edge — that clean, rolled cord running along the entire base of your project — is one of those details that makes a handmade piece look as though it was professionally designed and finished. For a shawl that will be worn and admired for years, a few extra minutes at the beginning is always worth it.