The two main ways to connect stitches for circular knitting
When you cast on stitches for knitting in the round, your working yarn and needle form a line, not a circle. You have to join that line into a loop before you knit the first row. The two methods that work are the loop join (slip the last stitch over the first) and the backward loop join (knit into the cast-on edge to close the gap). Both take less than a minute and produce a nearly invisible seam at the start of your project.
The loop join is faster and leaves almost no visible join line. The backward loop join gives you a slightly tighter connection and works better if your cast-on edge is loose. Neither method requires special tools or yarn. You choose based on how tight your cast-on usually runs and how much you care about a perfect join.
Key Takeaways
- The loop join works by slipping your last cast-on stitch over the first stitch, then knitting the first stitch through the loop to lock it in place.
- The backward loop join involves knitting into the cast-on edge between your first and last stitches to close the gap before you start the first round.
- Both methods work with any cast-on type and any needle size, and neither creates a visible bump or hole if done correctly.
- You must join before you knit the first stitch, or your stitches will not form a continuous circle.
The loop join: slip, knit, and lock
The loop join is the fastest method and the one most knitters reach for. After you cast on all your stitches, your working yarn hangs from the last stitch you made. Slip that last stitch onto your right needle (the one holding the cast-on stitches). Then slip it back over the first stitch on your left needle, the way you would bind off. This creates a loop that connects the end of your cast-on row to the beginning.
Now knit the first stitch on your left needle through the loop you just made. The loop tightens around that stitch and locks the join in place. You are now ready to knit the second stitch, and your stitches form a circle. The join line runs between the first and last stitches and is nearly invisible if your cast-on tension was even.
This method works with any cast-on and any yarn weight. It produces the least visible join and is the standard choice for most circular projects. The only drawback is that if your cast-on edge is very loose, the join can feel slightly loose too — but a gentle tug on the working yarn after you knit the first few stitches usually tightens it.
The backward loop join: knit into the edge
The backward loop join takes a few extra seconds but creates a tighter connection, especially if your cast-on runs loose. After you cast on, hold your needles so the cast-on edge faces you. Insert your right needle under the loop between your first and last cast-on stitches (the gap at the edge of your circle). Knit through that gap as if it were a stitch. This creates a new stitch that bridges the gap.
Once you have knitted into the edge, you have a complete circle of stitches. Knit the first cast-on stitch as normal, and you are ready to continue the first round. The join sits at the edge of your cast-on and is barely visible because it blends with the cast-on edge itself.
This method works best when your cast-on edge is loose or when you are using a stretchy yarn that tends to relax. It also works well for very small circumferences (like the top of a hat) where a tight join matters more. The trade-off is that it takes a few extra seconds and requires you to find the exact spot between the first and last stitches.
Avoiding common join mistakes
The most common mistake is twisting your stitches before you join. If your cast-on stitches spiral around the needle instead of lying flat, your join will twist too, and you will knit a spiral instead of a flat circle. Before you join, lay your needles flat and check that all your stitches sit in a single layer around the needle, not wrapped around it.
The second mistake is joining too loosely. If your join loop is slack, the gap between your first and last stitches will be visible and your fabric will have a hole there. After you join and knit the first stitch, gently pull the working yarn to tighten the join. You may need to tug a few times as you knit the first three or four stitches.
The third mistake is joining in the wrong direction. Your working yarn should come from the last stitch you cast on, not from the first. If you are holding the needle with the working yarn on the wrong end, slip your stitches to the other end of the needle before you join.
Which join to use for different projects
Use the loop join for most projects: hats, socks, sleeves, and any circular knitting where the join sits at a seam or edge that will not be highly visible. It is fast, reliable, and produces a clean join that disappears into the fabric. Use it as your default unless you have a reason to choose otherwise.
Use the backward loop join when your cast-on edge is very loose, when you are working with a stretchy yarn, or when the join sits in the middle of a visible area (like the top of a colorwork hat). It also works better for very small circumferences where every bit of tightness matters. If you are new to circular knitting, try both methods on a practice swatch and see which feels more natural to your hands.
Fixing a twisted join
If you knit a few stitches and realize your join is twisted, you can fix it without ripping back to the cast-on. Drop the stitches you just knit off your needle and unravel them back to the join. Untwist your cast-on stitches so they lie flat, then rejoin using either method. This takes about a minute and saves you from ripping back to the beginning.
To prevent twisting in the first place, lay your needles flat on a table after you cast on and before you join. Check that your stitches form a flat circle, not a spiral. This one extra step catches most twists before they happen.
Frequently Asked Questions
What if I cast on using a long-tail cast-on and the tail is in the way?
The tail sits at the edge of your cast-on and does not interfere with the join. Use it to weave in later. If it is very long and gets tangled in your needles, tie a loose knot in it to keep it out of your way while you join and knit the first few stitches.
Can I join in the round with straight needles?
No. Straight needles have a stop at one end, so you cannot slide stitches around to form a circle. You need circular needles (a cable connecting two needle tips) or double-pointed needles (a set of four or five short needles). Circular needles are easier for beginners.
Does the join create a weak spot in the fabric?
No. Once you knit a few stitches past the join, the connection is as strong as the rest of your fabric. The join is not a seam — it is straightforward the point where your cast-on edge closes into a circle. Tension it properly and it will hold.
What if my join keeps coming loose as I knit?
Pull the working yarn tighter after you join and after you knit the first stitch. If it still loosens, your cast-on edge may be too loose. Try the backward loop join next time, or cast on one extra stitch and decrease it away on the first round to tighten the join area.
Can I join in the round with a provisional cast-on?
Yes. Join using either method, then knit your rounds normally. When you are ready to pick up the provisional stitches, unravel the cast-on edge and place those stitches on a needle. The join point will be part of your fabric and will not unravel.