How to Sew a Beanie with Mattress Stitch (Step-by-Step + Video).

Learn how to sew a beanie with mattress stitch for a neat, stretchy seam. Simple steps for beginners, plus a video tutorial.

Sewing the seam is the last step of a flat-knit beanie, and it can make or break the finished look. A messy seam shows on the outside. A neat one almost disappears.

In this post, I’ll show you how to sew a beanie with mattress stitch, the method I use for all my straight-needle hats on Vimla Knit. It’s easy to learn, and it gives you an invisible seam that stays stretchy.

This is mattress stitch for beginners, so you don’t need any special skills. I’ve added simple steps and a video tutorial to help you along. And if you’re still looking for something to knit, you can find all my free beanie patterns on Vimla Knit. Let’s get started!

What Is Mattress Stitch?

Mattress stitch joins two knitted edges from the right side. You pick up the little horizontal bars between the stitches, going back and forth from one edge to the other. When you pull the yarn, the edges come together and the seam almost vanishes.

It’s the best choice for a knit hat because it keeps the fabric flexible. A tight, bulky seam can make a beanie feel stiff or pinch your head.

What You Need

• Your finished beanie, still flat
• A yarn needle (tapestry needle)
• The long tail of yarn from your cast-on or bind-off, or a new strand about three times the length of your seam

How to Sew a Beanie, Step by Step

1. Lay the beanie flat. Put the right side facing you, with the two side edges next to each other. Make sure the brim edges line up.

2. Join the bottom corner. Insert the needle into the bottom of one edge, then the bottom of the other edge. This anchors your seam.

3. Find the bars. Look one stitch in from the edge. Between the first and second stitch, you’ll see small horizontal bars, like the rungs of a ladder.

4. Go back and forth. Pick up one bar on one side, then one bar on the other. Repeat for 3 or 4 rows.

5. Pull gently. Tug the yarn until the edges meet. Don’t pull too hard, or the seam will pucker.

6. Keep matching the rows. Work up to the crown, picking up the same number of bars on each side so the rows stay level.

7. Weave in the end. Finish at the top, then weave the tail into the inside of the beanie.

Seaming the Ribbed Brim

If your beanie has a ribbed brim, take extra care. Line up the rib columns on both sides so the pattern continues across the seam without a break. A seam that cuts through a rib is the most noticeable mistake.

Video Tutorial

If you’d rather watch than read, this video shows the whole process slowly. It covers seaming stockinette and rib, smoothing out the seam, and fixing uneven lengths.

[Watch: How to Invisible Seam a Knit Hat with Mattress Stitch]

Video credit: All credit goes to Craft Fix knitting & crochet on YouTube. Thank you for this helpful tutorial!

Useful moments in the video:

• 2:41 Seaming a stockinette hat
• 10:04 Mattress stitch for rib
• 14:38 Weaving in the end

Tips for a Neat Seam

Sew from the right side so you can see how the seam looks as you go.

• Use the same yarn as your beanie, so the seam blends in.
• Check as you go. After a few rows, pull the seam closed to see how it looks. If it’s uneven, undo a few stitches and redo them.
• Keep the tension relaxed. The seam should stretch as much as the rest of the hat.

Final Thoughts

A good seam takes a little patience, but it’s worth it. Once you try mattress stitch, you’ll use it on every hat. I hope this helps you finish your beanie with a neat, comfortable seam.

If you’re ready to knit your next one, take a look at my free beanie patterns on Vimla Knit. There’s something for every skill level.

If you try it, please tell me in the comments how it went. Share your finished beanie on Instagram and tag me. I would love to see it!

FAQs