Knitting Tutorial: How to Do the Knitted Cast On

Learn how to do the knitted cast on with this beginner-friendly tutorial. All my tutorials are on this page: Knitting Tutorial Page.

If you’ve ever knit a raglan sweater from the top down, you’ve probably hit that point at the underarms where you have to cast on extra stitches—and if you’re like me, you want something sturdy, simple, and smooth for that spot. That’s exactly why I love using the knitted cast on. In this post, I’ll walk you through how to do the knitted cast on step-by-step, with written instructions that work for both right-handed and left-handed knitters.

Personally, I use the knitted cast on every single time I design a top-down raglan sweater, especially for underarm stitches. It blends right in, gives structure, and doesn’t get weirdly tight or loopy. You’ll see it in action in sweaters like the Youth Michael Pullover, the Rosemary Cardigan, and the Deborah Tee—all of which come in baby, youth, and adult sizes. I’ll include a link to those patterns a bit further down so you can try them out yourself.

Before we jump in, let’s talk materials. In the tutorial photos and my YouTube video, I used KnitPicks Heatherly Sport yarn (affiliate link) because it’s smooth, springy, and perfect for showing each step clearly. I’m also using KnitPicks Interchangeable Circular Needles (affiliate link), which are my go-to for almost every project.

What Is the Knitted Cast On?

The knitted cast on is a method of adding new stitches to your needle using your working yarn and one of your knitting needles. It’s beginner-friendly, simple to remember, and works great in places where you need to add stitches mid-project (hello, raglan underarms!).

You don’t need a long tail or any fancy prep. Just your working yarn and the needles you’re already using.

When to Use the Knitted Cast On

Here are a few of my favorite ways to use this method:

Underarms of raglan sweaters (like the Youth Michael Pullover, Rosemary Cardigan, or any version of the Deborah Tee)
Casting on stitches at the edge of a button band or neckline
When you’re mid-project and need to cast on extra stitches for a sleeve or body shaping
When you just don’t feel like estimating how much yarn to leave for a long-tail cast on (been there…)

Basically, if you need to add stitches and want something that looks neat and behaves well, the knitted cast on is a solid go-to.

Materials I’m Using in This Tutorial

Yarn: KnitPicks Heatherly Sport (affiliate link)
Needles: KnitPicks Interchangeable Circular Needles (affiliate link)

These materials make it easy to see your stitches and handle the cast on without splitting the yarn or fighting with your tools. I highly recommend both if you’re looking to upgrade your knitting setup.

How to Do the Knitted Cast On (Written Instructions)

Before we get into it, let’s clarify our terminology:

Working Needle: This is the needle doing all the knitting.
Holding Needle: This is the needle holding your stitches—whether you’re starting with a slipknot or adding on mid-row.

These instructions are written for both right-handed and left-handed knitters—just remember the working needle is the one doing the action, regardless of hand dominance.

Step-by-Step: How to Do the Knitted Cast On

Make a Slipknot and place it on the holding needle. This is your first stitch.

Insert your working needle into the stitch on the holding needle, just like you’re about to knit.

Wrap the working yarn around your working needle.

Pull a loop through as if you’re knitting a stitch.

Now, don’t slide the stitch off the holding needle. Instead, take the loop on your working needle and place it onto the holding needle next to the original stitch.

You’ve now added one stitch! Repeat steps 2–5 for each new stitch you want to add.

That’s it! It’s essentially like knitting, but instead of finishing the stitch, you’re transferring the new loop back to your holding needle.

Left-Handed Tutorial Video on YouTube

If you’re a left-handed knitter (like many of my readers), you’re not alone. I filmed a step-by-step left-handed video tutorial for how to do the knitted cast on, and you can watch it on my YouTube channel.

I show the cast on from the left-handed perspective, so you don’t have to mirror anything or try to translate it as you go. (And I promise, no confusing “just do it backwards” instructions here!)

Why I Use the Knitted Cast On in My Patterns

Let’s circle back to why this technique is so useful for raglan sweaters—especially top-down designs. When you’re working top down, you often reach the point after separating the sleeves where you need to cast on extra stitches for the body under the arms. This is where the knitted cast on shines. It creates a smooth, non-gappy foundation that transitions beautifully into the body of the sweater.

You’ll see it used in these three of my favorite top-down raglan sweater patterns:

👉 Youth Michael Pullover Free Pattern – a simple wide ribbed raglan pullover that’s comfy and classic.

👉 Rosemary Cardigan Free Pattern – a long sweet open cardigan that layers perfectly in every season.

👉 Deborah Tee Free Pattern – a short-sleeve tee that works up quickly and comes in baby, youth, and adult sizes.

If you’re working on any of these patterns (or anything with raglan shaping), try using the knitted cast on when you reach the underarms. It keeps everything neat and consistent.

Troubleshooting Tips

Here are a few quick fixes in case things don’t feel quite right:

Too tight? Loosen your tension as you pull the new loop through before placing it on the holding needle.
Too loose? Make sure you’re not stretching the loop too much before placing it back on.
Twisted stitches? Double-check that you’re not accidentally wrapping your yarn in the wrong direction.

The more you practice, the more muscle memory will kick in. It gets easier fast!

Practice Makes Progress

If you want to try this technique before diving into a full sweater, here’s a little practice idea:

Cast on 10 stitches using the long-tail cast on.
Work a few rows in garter stitch.
Then, use the knitted cast on to add 5 stitches at the start of the row.
Keep knitting and see how it looks and feels.

It’s a great way to see how the edge forms and to get comfortable with the motion before doing it in a real project.

Final Thoughts

Learning how to do the knitted cast on was a turning point in my knitting journey. It unlocked top-down sweaters, mid-project shaping, and so much more. Once you try it a couple of times, it’ll be second nature—and you’ll find yourself reaching for it in all sorts of projects.

Don’t forget to check out the Youth Michael Pullover, Rosemary Cardigan, and Deborah Tee if you want a great excuse to use this cast on in action. All three patterns (and their baby and adult versions) are free to download along with many others. head over to the free pattern page for over 200 free knitting patterns to practice on.

Did you try this cast on yet? I’d love to hear what project you’re using it for! Drop a comment below and let me know if you found the tutorial helpful—or if you’re trying it for the first time.

Happy knitting!

This post contains affiliate links, which means I may earn a small commission at no extra cost to you if you purchase through those links. Thank you for supporting my blog!

The Knit in the Womb Blog