Mattress Stitch in Knitting: A Beginner's Guide

by Janice Jones   

The mattress stitch in knitting is a useful way to sew two pieces of fabric together in a way that is nearly invisible.  It is a  professional way to finish your knitted projects such as a sweater or vest. 

But as a beginner, you might be asking why should I learn it.  The words "expert, professional or experienced," conjures up feelings of "difficulty, complex, or intricate."

Those are the feelings I had when first encountering this knitting technique. I am going to break it down so the mattress stitch does not evoke such thoughts for you.

Why is the Mattress Stitch in Knitting Important in Knitting?

A small sample of the mattress stitch worked in stockinette stitch.

The mattress stitch is essential in knitting because it allows you to seamlessly join knitted pieces.

Instead of using a visible and bulky method like whipstitch or backstitch, the mattress stitch creates an invisible seam that blends seamlessly with the surrounding stitches. 

In this article we will concentrate in using the mattress stitch to sew up two swatches in the stockinette stitch fabric.  You can also use this to sew swatches in other stitch patterns such as garter or rib, but that is a skill for a different article.

Guide to the Mattress Stitch Technique

For the purposes of this tutorial, you will need:

supplies needed for the mattress stitch in stockinette pattern

Step One:  Prepare Two Swatches to be Seamed

For this tutorial, you will need to create two small swatches of stockinette stitch.  I knit two swatches in a light colored acrylic yarn, but you can use whatever scrap yarn you have.  Both swatches need to have the same number of rows.

My swatches are 2.5 x 4 inches each worked on US 8 (5.0 mm) needles and #4 Worsted Weight Yarn. I used Lion Brand, Schitt's Creek, Color 4100 (Rose Apothecary).

For each swatch I cast on 15 stitches and worked a total of 34 rows.  Your two swatches do not need to be exactly the same as mine. Bind off but do not weave in ends.  Leave a long tail on at least one swatch about 3 times the length of your swatch.  

Step Two:  Block Your Swatches

I find it easier to make the mattress stitch if the swatches are blocked.  Acrylic yarn is not as easy to block, but blocking will still help as the stockinette stitch tends to curl making it difficult to work with when sewing swatches together.

Step Three:  Identify the Cast on and Bind off Edges and Match Up

Lay the pieces you want to join side by side with the right sides facing up. Make sure the edges you want to seam are even and aligned, and that the cast on edges are match up.  

You will work from the cast on edge towards the bind off end.

Swatch of stockinette stitch showing the cast on and bind off rows

Step Four:  Identify Where You Will Stitch

The mattress stitch seam is made between two columns of stitches, the selvage stitches and the edge stitches.

A stockinette stitch swatch with the selvage and edge stitches labeled

Grab Your Tapestry Needle and Get Started

Thread your tapestry needle with either the long tail still attached. For demonstration purposes, I am using a contrasting color so it is easier to see.

You can start seaming on either side, though I find it easier to start on the right because I am right handed.

Study the side edges of either swatch. There should be a little bar between the stitches or "Vs." Think of them as a little ladder. You will be working with the bars or rungs of the ladder only.

To make the mattress stitch, locate the little bars between the column of stitches or little VsYou will work the mattress stitch by picking up these little bars, one at a time.

Step Five:  Begin with a Figure 8 to Connect Both Swatches

But first, you will create a figure 8 at the base of the cast on edge. To make the figure 8 join, lay the two swatches side by side, lining up the two swatches so that both cast on eduges are at the bottom and both bind off (cast off) edges are at the top. Always work on the right side of the fabric.

You will make the figure 8 join in the cast on edge and then work the seam up towards the bind off edge.

Insert the needle between the first stitch of the right swatch from back to front. 

Then insert the needle from back to front between the first stitch on the left swatch.

Bring the tapestry needle back to the left swatch and go through the exact same stitch that you did initially. You've created a figure 8.

Beginning the mattress stitch with a figure 8.
Two stockinette stitch pattern swatches are being sewn together with the mattress stitch

Step Six:  Sew the Mattress Steam

Move from the stitch on the right piece to the corresponding bar on the left piece, being careful not to miss any bars.

Pick up that bar and then move to the corresponding bar on the right piece of fabric. 

Continue to pick up the bars, one by one but do not tighten the seam.

The mattress stitch as been worked about one inch without tightening

Step Seven:  Pull the Seam Closed

After you've worked about an inch, tug on the yarn to close the seam, but don't pull too tightly! Your seam will buckle and not lay flatly if you pull too tightly. If this happens gently stretch it out before creating another stitch.

The mattress stitch has been worked and now is being tightened manually
The mattress stitch has been pulled tight

Continue to the top of the seam.

Step Eight:  Secure the Seam

Secure the seam: To secure the seam, repeat the figure 8 and then weave in the ends.

The Appearance of the Mattress Stitch Seam

When finished, the join you created with the mattress stitch should be mostly invisible on the right side.  On the wrong side, it will look like a column of stockinette stitch.  

The right side of the mattress stitchMattress Stitch Seam: Right Side
The wrong side showing of the mattress stitch seam on stockinette stitch fabricMattress Stitch Seam: Wrong Side

Tips and Tricks for Perfecting the Mattress Stitch.

Here are some tips and tricks to help you perfect the mattress stitch technique:
1. Tension is key: Pay attention to the tension of your stitches as you work the mattress stitch. Aim for a tension that matches the surrounding stitches to create an invisible seam.

2. Block your pieces: Before seaming, it is recommended to block your knitted pieces. Blocking helps even out any discrepancies in size and shape, making the seaming process easier and ensuring a more polished finish.

3. Use removable stitch markers: To keep track of your stitches and ensure accurate seaming, place removable stitch markers at regular intervals along the edges of your knitted pieces.

4. Pull the seams apart:  Pull the edge seams from the selvage stitches to show the little bars.

5. Practice on scrap yarn: If you are new to mattress stitching, practice it before attempting it on your project. This will help you get a feel for the technique and build confidence.

Common Mistakes to Avoid When Using the Mattress Stitch in Knitting

While the mattress stitch is a relatively straightforward technique, some common mistakes can affect the quality of your seams. Here are a few to watch out for:

  1. Skipping stitches: Stitch through each corresponding stitch on both pieces. Skipping stitches can result in a visible gap or uneven seaming.
  2. Pulling too tight: Avoid pulling the yarn too tight when working the mattress stitch. This can distort the fabric and create puckering along the seam. Aim for a tension that matches the surrounding stitches.
  3. Misaligning edges: Ensure that the edges of your knitted pieces are correctly aligned before seaming. Misaligned edges can lead to wonky seams and an uneven finished product.  

Projects that benefit from the mattress stitch

The mattress stitch is a versatile technique used in various knitting projects. Here are some examples of projects that benefit from the mattress stitch:

  • Sweaters, vests, and cardigans: Seaming the sleeves to the body of a sweater or cardigan using the mattress stitch creates a seamless and polished finish.
  • Scarves and shawls: Joining the ends of a knitted scarf or shawl using the mattress stitch ensures an invisible and uninterrupted pattern.
  • Hats and caps worked flat: When making a hat that is worked flat and then seamed, a mattress stitch creates an invisible join.
  • Afghans and blankets: When knitting Afghans or blankets in separate squares, panels, or pieces, the mattress stitch allows you to assemble the pieces seamlessly into a cohesive whole.


The mattress stitch is a knitting technique every knitter should have in their repertoire. It allows you to achieve seamless seams that elevate the overall look of your knitted projects.

By following the step-by-step guide, practicing the tips and tricks, and avoiding common mistakes, you can master the art of mattress stitching and create beautifully finished garments and accessories. 

Happy Knitting, Smart Knitter!


Mattress Stitch in Knitting:  Pin for Future Reference

Three photos of the mattress stitch on a pin imageMattress Stitch in Knitting

If you found this tutorial helpful, may I suggest some of my other articles

About Janice

Hi, I’m Janice, the voice behind Smart-Knit-Crocheting. I love to knit and crochet and even more, I love teaching others what I know.

Though I learned to knit and crochet as a child, I didn’t get serious about these amazing hobbies until I retired. I’m a certified knit and crochet instructor through the Craft Yarn Council and am working on becoming a Master Hand Knitter through The Knitting Guild Association.

I’m currently living with my husband of over 50 years and our 7 Shih Tzu dogs.

I love hearing from you, so please drop me a line and let me know what you’re working on, whether you love knitting or crocheting more, and if you have any questions. Please visit my about me page for more information.

Happy Crocheting