Knit fabrics are some of the most comfortable and versatile fabrics you can sew. They’re used for everything from T-shirts and pajamas to leggings, dresses and activewear. But many sewists avoid knits because they stretch, curl, shift and sometimes seem impossible to control.
The good news? Sewing knit fabric is much easier once you understand a few basics.
I still remember the first time I tried sewing knit fabric on my sewing machine. It was a disaster! This was way before YouTube and Facebook groups for help. I sat and cried for a bit, and then I called my mommy! Having a mom that’s a professional tailor does have its perks. After regaining my composure and pulling out some test fabric I was ready to go. In this post I’ll share my top tips to make sewing with knits easy.
In this guide, you’ll learn:
- What knit fabric is
- The best needles and thread for knits
- Which stitches and machine settings to use
- Helpful tools and supplies
- Common mistakes to avoid
- Whether you need a serger
What Is the Best Way to Sew Knit Fabric?
The best way to sew knit fabric is to use a ballpoint or stretch needle, quality polyester thread, and a stretch-friendly stitch such as a narrow zigzag or lightning bolt stitch. Let the machine feed the fabric without pulling it, and always test your settings on scraps before starting your project.
What Is Knit Fabric?
Knit fabric is made by looping yarn together instead of weaving threads over and under each other. This construction gives knits their natural stretch and flexibility, which makes them ideal for comfortable garments.
Common knit fabrics include:
- Jersey knit
- Rib knit
- Interlock knit
- Ponte knit
- French terry
- Double-brushed polyester (DBP)
- Athletic knit
- Sweater knits
Some knits stretch in only one direction, while others stretch both ways. Two-way stretch knits stretch across the width; four-way stretch knits stretch in both length and width.
Stretch percentage matters too, because many patterns need a specific amount of stretch to fit properly. Learn how to measure knit fabric stretch percentage before you buy fabric for a knit pattern.
Knit Fabric vs Woven Fabric
| Knit fabric | Woven fabric |
|---|---|
| Naturally stretches | Little or no stretch |
| Made with interlocking loops | Made with threads crossing at right angles |
| Soft and flexible | More structured |
| Sewn with stretch stitches | Sewn with straight stitches |
| Common in T-shirts, leggings, loungewear | Common in shirts, pants, bags and home decor |
For a closer look at both, see my guide to the types of fabric for sewing.
Why Can Knit Fabric Be Difficult to Sew?
Knits can be challenging because their stretch makes them shift, curl or stretch out while you sew. Most problems come down to the wrong needle, the wrong stitch settings, or pulling the fabric through the machine.
Common issues include:
- Wavy seams
- Skipped stitches
- Curled edges
- Popped stitches
- Uneven hems
- Fabric stretching out of shape
What Needle Should You Use for Knit Fabric?
Most knits sew best with a ballpoint (jersey) or stretch needle. These needles have a rounded tip that slides between the fibers instead of piercing them. Skip the universal needle: the wrong needle is the most common cause of skipped stitches, holes and frustration.
Knit fabric needle quick guide
| Knit fabric | Needle type | Size |
|---|---|---|
| Lightweight jersey | Ballpoint | 70/10–75/11 |
| T-shirt knit | Ballpoint | 80/12 |
| Stretch knits with spandex | Stretch | 75/11–90/14 |
| Ponte knit | Stretch | 80/12–90/14 |
| French terry | Ballpoint | 80/12–90/14 |
| Rib knit | Stretch | 75/11–80/12 |
| Heavy sweater knits | Ballpoint | 90/14 |
Schmetz stretch and ballpoint needles are a reliable choice, and Organ stretch needles are another good option.
Signs you need a different needle
- Skipped stitches
- Snagged fabric
- Uneven stitching
- Holes in the fabric
- Popping sounds while sewing
What Thread Works Best for Knit Fabric?
Polyester thread is usually the best choice for knits. It has a little “give,” so it stretches with the fabric. Cotton thread has less stretch and can break when the seam stretches.
Use: quality 100% polyester or a poly-blend thread.
Avoid: old thread, cheap thread, and heavy-duty thread unless your project needs it.
For more on choosing thread, see my Ultimate Sewing Thread Guide.
What Stitch Should You Use for Knit Fabric?
Use any stitch that lets the fabric stretch after sewing. A regular straight stitch can pop when the fabric stretches.
Narrow zigzag stitch
If your machine doesn’t have a stretch stitch, a narrow zigzag works beautifully.
- Width: 0.5–1.5
- Length: 2–2.5
Works well for: T-shirts, basic garment construction and general knit sewing.
Lightning bolt stitch
This is the stretch stitch on many machines. It looks like a narrow lightning bolt and stretches with the seam.
Best for: stretchy fabrics, athletic fabrics and leggings.
Triple stretch stitch
This stitch sews each stitch three times for extra strength.
Best for: high-stress seams, activewear and children’s clothing.
Twin needle stitch
A twin needle gives you professional-looking hems. It sews two rows of stitching on top with a zigzag underneath, so the hem can stretch.
Perfect for: T-shirt hems, sleeve hems and knit dresses.
Want professional hems? Learn how to hem knit fabric with a twin needle.
Sewing Machine Settings for Knit Fabric
Every machine is a little different, so treat these as starting points and test on scraps of your actual fabric.
- Stitch length: 2–2.5 for a narrow zigzag. A slightly longer stitch helps prevent wavy edges when topstitching.
- Stitch width: 0.5–1.5 for a narrow zigzag. For a stretch stitch, start with your machine’s automatic setting.
- Tension: start with your machine’s normal setting. If seams pucker or look tight, lower the tension slightly.
- Speed: sew slowly and steadily, especially when you’re starting out.
Can You Sew Knit Fabric on a Regular Sewing Machine?
Yes! You can absolutely sew knits on a regular sewing machine. You just need the right needle and stitch settings. Many sewists make knit garments for years without ever owning a serger.
Should You Use a Serger for Knit Fabric?
You don’t need a serger to sew knits, but it makes sewing faster and gives a more professional finish. Knits are where sergers really shine.
For most knit seams, I use a 4-thread overlock stitch. It sews, trims and finishes the edge in one pass, and it stretches with the fabric.
Benefits of a serger:
- Faster sewing
- Professional seam finishes
- Built-in stretch
- Trims and finishes seams at the same time
Great serger projects: T-shirts, pajamas, loungewear, leggings and baby clothes.
Ready to finally learn your serger?
If your serger is still in the box or collecting dust, my Serger 101 course walks you through:
- Threading your machine
- Understanding differential feed
- Adjusting tension settings
- Beginner-friendly projects
- Professional finishing techniques
What Tools Help When Sewing Knit Fabric?
These tools make knits much easier to handle:
- Walking foot
- Sewing clips
- Wash-away sewing tape
- Twin needle
- Rotary cutter and cutting mat
Walking foot
A walking foot feeds the top layer of fabric at the same rate as the bottom layer. On knits, that keeps the top layer from stretching ahead of the bottom one, which is one of the main causes of wavy seams. Learn more in my guide on how to use a walking foot, and see what other feet can help in my Sewing Machine Feet Guide.
Sewing clips
Sewing clips hold layers together without piercing or distorting the fabric the way pins can. I do have several containers of them, but I don’t use them as often as pins. That’s mostly because I was taught with pins and I’m in the habit of reaching for my pincushion.
Wash-away sewing tape
Wash-away sewing tape holds fabric in place while you sew, and it’s especially handy for knit hems and necklines. It lies flat, so it won’t distort the fabric the way pins can, and you can usually stitch right through it. It dissolves in the wash and leaves no residue. Follow the directions for your brand, since they vary a little.
Rotary cutter and mat
A rotary cutter cuts knits without lifting them off the table, so the fabric doesn’t shift or stretch while you cut. Keep your blade sharp and your mat in good shape with these tips on how to care for a rotary cutter and cutting mat.
Tips for Cutting Knit Fabric
- Keep the fabric fully supported on the table, so it doesn’t hang off the edge and stretch.
- Use pattern weights instead of pins when you can.
- Cut slippery knits in a single layer.
- Pay attention to the direction of greatest stretch, which usually runs around the body.
- Test how your fabric behaves before cutting.
Common Mistakes When Sewing Knit Fabric
Pulling the fabric while sewing
Let the machine feed the fabric on its own. Guide it gently, but don’t push or pull.
Using the wrong needle
Skipped stitches are usually a needle problem. Switch to a ballpoint or stretch needle.
Ignoring stretch percentage
A knit pattern’s fit depends on the fabric having the right amount of stretch, so check it before you cut.
Stretching hems while sewing
Stretching the fabric as you hem creates wavy edges. Wash-away tape or a twin needle helps.
Skipping test stitches
Always test your settings on scraps of the same fabric first.
What Is the Easiest Knit Fabric for Beginners?
Ponte knit and French terry are usually the easiest knits for beginners. They’re more stable and less likely to curl than lightweight jersey.
Start with a simple project before moving on to fitted garments. Good beginner projects include:
- Pajama pants
- Lounge shorts
- Simple skirts
- Headbands
- T-shirts
- Pajama sets
Frequently Asked Questions
Why does knit fabric get wavy when sewing?
Wavy seams usually happen when the fabric stretches as you sew. That can come from pulling the fabric, too much presser foot pressure, or the wrong stitch settings. A walking foot and a slightly longer stitch can help.
Do I need a serger to sew knit fabric?
No. A regular sewing machine with the right needle and stitch settings sews knit fabric successfully.
What needle should I use for knit fabric?
Use a ballpoint (jersey) needle for most knits, and a stretch needle for knits with spandex.
Can I use a straight stitch on knit fabric?
It’s best not to for seams that need to stretch, because a straight stitch can pop. Use a narrow zigzag or stretch stitch instead.
Do I need to adjust my presser foot pressure?
Usually not. The right needle and stitch matter most. If your seams are still wavy and your machine has adjustable pressure, lowering it slightly can help.
Give Knit Fabric a Try!
Knit fabric can seem intimidating at first, but the right needle, stitch settings and techniques make a huge difference. Start with a beginner-friendly knit, test your settings on scraps, and practice before moving on to full projects.
Soon you’ll be confidently sewing comfortable T-shirts, pajamas, dresses and stretchy garments.
Learn More About Fabric
- How to Measure Knit Fabric Stretch Percentage
- How to Hem Knit Fabric With a Twin Needle
- Types of Fabric for Sewing: Woven, Knit & Nonwoven
- Ultimate Fabric Sewing Guide: Tips for Sewing Every Fabric Type
- How to Choose Fabric for a Sewing Project
- How to Use a Walking Foot
Learn to Sew or Improve Your Skills
Do you want to start sewing but need a helping hand with the basics? Our Sewing 101 course has everything you need to start sewing confidently and improve your skills. Ready to tackle your serger? Check out Serger 101.
