The 4 Essential Serger Stitches Every Beginner Must Know

A serger can look intimidating with its multiple cones of thread and complex loopers. But surprisingly, you only need to master four basic stitches to handle 95% of your sewing projects.

Once you understand these four, you’ll be able to tackle everything from rugged activewear to delicate silk scarves.

1. The 4-Thread Overlock (Safety Stitch)

This is the default setting on most machines and the one you will use most often.

• Setup: Uses 2 needles and 2 loopers (4 threads total).
• Why use it: It creates a strong, durable seam that stitches the fabric together and finishes the edge at the same time.
• Best for: Constructing garments, especially knits (t-shirts, leggings) and woven fabrics that need strength. It’s called a “safety” stitch because the second needle adds an extra line of security.

2. The 3-Thread Overlock

Take out one of the needles, and you have the 3-thread overlock.

• Setup: Uses 1 needle (left or right) and 2 loopers.
• Why use it: It’s stretchier and less bulky than the 4-thread version. However, it’s not as strong for seams that will be under tension.
• Best for: Finishing raw edges of fabric before sewing them on a regular machine (like pressing seams open), or for blind hemming. It saves thread compared to the 4-thread.

3. The Rolled Hem

This is the “magic trick” of the serger world. It transforms a raw edge into a tiny, tight, beautiful finish.

• Setup: Uses 1 needle (usually right) and 2 loopers. You usually need to remove the stitch finger (or flip a switch) and tighten the lower looper tension significantly.
• Why use it: It rolls the fabric edge under itself and wraps it completely with thread.
• Best for: Lightweight fabrics like chiffon, silk, or voile. It’s perfect for the edges of napkins, scarves, or the bottom of a airy summer dress.

4. The Flatlock

The flatlock is a unique stitch that looks like a seam on the outside but can be pulled flat.

• Setup: Uses 2 or 3 threads with very specific tension settings (usually loose needle tension).
• Why use it: You sew the fabric with the wrong sides together, and then pull the two pieces apart. The stitches flatten out, creating a ladder effect on one side and loops on the other.
• Best for: Decorative seams on sportswear (like yoga pants), or for joining bulky fleece where you don’t want a thick seam allowance pressing against your skin.

Getting Started

Don’t try to learn them all at once. Start with the 4-thread overlock—it’s likely what your machine is threaded with right out of the box. Get comfortable with the speed and the cutting knife.

Once you are confident, try removing a needle for the 3-thread, and then—when you’re feeling brave—tackle the tension adjustments for the rolled hem.

Want to know more about how these machines differ from your standard setup? Check out our guide on Serger vs. Sewing Machine or learn exactly what a serger is.