Casting on with circular needles works the same way as with straight needles, but the needle itself is different

A circular needle is two short needle tips connected by a flexible cable. When you cast on, you use only one tip to loop yarn onto the needle, just as you would with a straight needle. The cable stays out of your way during casting on — it does not participate in the cast-on row. Once your stitches are on the needle, you can distribute them around the cable and begin knitting in the round, or you can knit flat using both tips as you would with straight needles.

The most common cast-on methods — long-tail, cable, and thumb cast-on — all work identically on circular needles. The only real difference is that a circular needle gives you more room to hold stitches without them falling off the end, which is helpful when you are casting on a large number of stitches for a hat, sweater, or blanket.

Key Takeaways

  • Cast on using only one needle tip, holding the cable out of the way, exactly as you would with a straight needle.
  • The long-tail cast-on is the fastest method and works well on circular needles because the cable gives you space to hold many stitches.
  • Make sure your cable is not twisted before you start knitting in the round, or your stitches will spiral and cannot be fixed.
  • If you are knitting flat with a circular needle, treat both tips like straight needles and ignore the cable entirely.
  • Circular needles come in different cable lengths — choose one where your cast-on stitches fit comfortably without bunching or stretching.

Set up your needle and yarn before you begin

Hold the circular needle in your dominant hand, gripping one of the two needle tips between your thumb and forefinger. Let the cable and the other tip hang down. This is the tip you will use for casting on. The other tip will stay empty until you have finished casting on all your stitches.

If you are using the long-tail cast-on, measure out a length of yarn from the ball. A rough guide: for every stitch you plan to cast on, you need about one inch of yarn. So if you are casting on 60 stitches, measure out roughly 60 inches (5 feet) of yarn. Tie a loose loop at the end of this measured length — this loop will go on your needle first.

If you are using the cable cast-on or thumb cast-on, you do not need to measure yarn in advance. You can begin casting on directly from the ball.

Long-tail cast-on: the fastest method for circular needles

Make a loop with your measured yarn tail. Hold the loop in your left hand with your thumb and forefinger, keeping the yarn tail and the working yarn (the yarn attached to the ball) separate. Insert the needle tip through the loop from front to back, then pull the loop onto the needle. This is your first stitch. Tighten it gently so it sits on the needle without sliding.

Now hold the needle in your right hand and the two yarn strands in your left hand. Pinch the yarn tail between your left thumb and forefinger, and pinch the working yarn between your left middle finger and forefinger. Your left hand should look like you are making a "V" with your thumb and two fingers, with yarn running over each one. This is called the "V-hold" and it is the foundation of the long-tail cast-on.

Insert the needle tip upward through the loop on your thumb, then over the yarn on your forefinger, then back down through the thumb loop. Pull the yarn tail gently to tighten the new stitch on the needle. Repeat this motion — up through the thumb loop, over the forefinger yarn, down through the thumb loop, tighten — until you have cast on the number of stitches you need. Each motion creates one stitch.

This method is fast because both hands work at once, and the cable on a circular needle gives you plenty of room to hold stitches as they accumulate. Stop when your stitches reach the cable, and they will not fall off the end of the needle.

Cable cast-on: a sturdy edge for structured projects

The cable cast-on creates a firm, neat edge and works well for projects that need structure, like the cuffs of socks or the edges of blankets. Start by casting on two stitches using the long-tail method or by straightforward looping yarn onto your needle twice.

Hold the needle in your right hand. Insert the tip between the two stitches on the needle (not through them, but between them), wrap the working yarn around the tip as if you were knitting, and pull a new loop through to create a third stitch. Slip this new stitch onto the left needle tip (the empty one). Repeat: insert between the last stitch and the one before it, wrap yarn, pull through, slip onto the left tip. Continue until you have cast on all your stitches.

The cable cast-on is slower than the long-tail method because you are working with both hands and the needle tips, but the result is a very stable edge that does not curl or stretch.

Thumb cast-on: the simplest method with no measuring

The thumb cast-on requires no measuring and no special hand position. Make a loop with the working yarn, slip it onto your needle, and tighten it gently. This is your first stitch. Now wrap the working yarn around your left thumb, holding it in place with your left forefinger and middle finger. Insert the needle tip upward through the loop on your thumb, then pull the yarn to tighten the new stitch on the needle. Repeat until you have cast on all your stitches.

This method is the easiest to learn because it uses only one hand (your left hand holds the yarn loop, your right hand works the needle). The edge is less sturdy than the cable cast-on, but it is perfectly fine for most projects. The downside is that it is slower than the long-tail cast-on, so it is best for projects where you are casting on fewer than 30 stitches.

Check that your cable is not twisted before you knit in the round

Once you have cast on all your stitches, lay the circular needle flat on a table and look at it from above. The stitches should form a circle, and the cable should lie flat without any twists or loops. If the cable is twisted, your stitches will spiral as you knit, and you cannot fix this mistake after you have started knitting.

To untwist the cable, gently slide all your stitches off the needle tips onto the cable itself, then straighten the cable by hand. Once it is flat, slide the stitches back onto the tips and begin knitting. If you are knitting flat (not in the round), the cable twist does not matter because you are turning the work at the end of each row.

Common mistakes and how to avoid them

The most common mistake is casting on too many stitches for your cable length. If your stitches are bunched tightly on the tips and stretched across the cable, they will be uncomfortable to work with and may slip off. Choose a cable length that matches your project: a 16-inch cable for hats and small circumferences, a 24-inch cable for sweaters and medium circumferences, and a 32-inch or longer cable for blankets and large circumferences.

Another mistake is twisting the cable before you start knitting in the round. Check for twists before you knit the first stitch, because once you have knitted a few rows, the twist is permanent and you will have to rip out your work.

A third mistake is casting on too tightly. If your cast-on stitches are very tight, they will be hard to knit into on the first row, and your edge will look bunched. Cast on with a relaxed tension, letting each stitch sit loosely on the needle. You can always tighten the edge later by weaving in the yarn tail.

Frequently Asked Questions

Do I have to knit in the round with a circular needle, or can I knit flat?

You can knit flat with a circular needle by treating it exactly like two straight needles. Knit one row, turn the work, and knit the next row in the opposite direction. The cable straightforward stays out of the way. Many knitters prefer circular needles for flat projects because they distribute the weight of the work more evenly across both hands.

What if I cast on too many stitches and they do not fit on the cable?

Slide all the stitches onto the cable itself, bunching them together temporarily. Once you have cast on all your stitches, you can distribute them more evenly around the cable. If the cable is still too short, you will need a longer one — measure your cast-on stitches and choose a cable that is slightly shorter than that circumference.

Can I use the same cast-on method I use for straight needles?

Yes. Every cast-on method works on circular needles. The only difference is that you have more room to hold stitches on the cable, so you are less likely to drop them off the end. Choose the cast-on method you are most comfortable with.

How tight should my cast-on stitches be?

Cast on with a relaxed tension so that each stitch slides easily on the needle and you can insert your working needle through it without struggling. If your cast-on is too tight, your first row will be difficult to knit. If it is too loose, your edge will look sloppy. Aim for the middle ground — stitches that sit comfortably on the needle without bunching or sliding.

What if my cable is kinked or stiff?

Soak the circular needle in warm water for a few minutes, then gently straighten the cable by hand and lay it flat to dry. Most cables become more flexible with use. If a cable is permanently kinked or cracked, the needle is no longer usable and should be replaced.