Our quick guide to stitch types - AE Sewing Machines

Stitches are often small and sometimes invisible, but they are at the core of every sewing operation! If you aren’t using the correct stitch for your application, the whole thing may fall apart or else not be fit for purpose. In this quick guide to stitch types, we run through several categories of industrial sewing stitches and the most commonly used within them. Stitch classifications aren’t the most interesting topic but understanding the advantages and disadvantages of the various stitch types which can be used will help you to choose the right one for your project!

Single thread chain stitches:

Chain stitches fall into class 100. They are created when two or more threads are combined to produce a stitch which is chain-like in appearance. They are formed by one continuous thread which is looped back on itself, meaning there is no bobbin thread. The stitches created are slightly larger than other types and have a distinctive “roping” effect consisting of a thick textured line. They are frequently used for stitching decorative details on clothing and sometimes found on the waistband and leg seams of jeans.

Advantages: Distinctive decorative look. More seam elasticity than lockstitches.

Disadvantages: Unravels relatively easily. Can be laborious to sew.

101 – A single thread chainstitch. This stitch is formed using one sewing thread which comes from the sewing needle. The thread interloops with itself to create a neat stitch which is commonly used for temporary stitching or tacking. It is also used for decorative purposes.

103 – A single thread blind stitch. This stitch is a derivative of stitch type 101 is used for blind hemming. The stitch is formed using a curved needle which enters and exits the fabric from the same side carrying a needle thread. This thread interloops with a blind looper on the surface of the material. It is often used for applications such as hemming on trousers and skirts. This stitch is invisible on the surface of the garment, which is where the term blind hemming comes from.


Lockstitches fall into class 300 and are made when two threads lock together at minor intervals. They are formed with a needle thread and a bobbin thread which lock together. The needle thread is introduced from one side of the fabric, then caught by a rotary hook and interlaced with a thread underneath, which forms the stitch. It is arguably the most commonly used stitch type!  

Advantages: Does not unravel easily. Is reversable as it appears the same on both sides of the material. Uses the least amount of thread. Provides excellent seam security. Has a wide range of uses. Is quick and cheap. Produces a flat stitch.

Disadvantages – Has poor extension (301). Can be more susceptible to thread breakage. Low productivity due to need to frequently change the under-thread bobbin.

301 - The classic single needle lockstitch, this stitch appears as a neat straight line of stitching with the two threads twisting together in the centre of the seam. It is a popular choice for top stitching and general all-round sewing. The 301 twin-needle lockstitch is essentially the same except the second needle means it produces two parallel lines of stitching.

304 - The lockstitch zigzag stitch, this stitch works in a similar way to the 301 lockstitch but instead forms a zigzag pattern. It is formed by the interlocking of a needle and bobbin thread, with the needle bar moving laterally as the material is fed to creating a symmetrical zigzag pattern. The main difference in application between this and the 301 class is that this variation can be stretched and therefore is often used when a higher seam elongation is required. It is therefore a popular choice for attaching elastic/lace to lingerie.

Multithread chain stitches:

Multithread chain stitches (or double locked chain stitches) fall into class 400. They are formed when one or more needle threads move through the fabric and interconnect with a group of looping threads on the underside of the garment. The resulting stitch appears different on the top and bottom of the fabric. It is used for a wide variety of applications such as sewing blazers and adding decorative stitching to belts.

Advantages: Appears similar to a standard chain stitch but has increased durability and elongation. When sewn correctly, it is less likely to result in puckered seams than a standard chain stitch.

Disadvantages: Consumes more thread than a standard chain stitch. Still unravels easily. Isn’t reversable. Bulkier seams than a lockstitch.

401 – A two thread chainstitch, formed with one needle thread and one looper thread. The threads cross over on the underside of the fabric. It is used for applications such as joining trouser panels, sewing waist bands and the inseams of jeans.  

402 – Forms a stitch similar to 401 but in a zigzag pattern for higher elasticity. It is used to attach waist band lining to men’s trousers.

406 – A twin needle coverseam stitch. It is formed using two needle threads and one looper thread. It is often used to cover a raw edge on bottom hems. It produces a flat and comfortable seam which is useful for cover seaming, sewing belt loops, binding, and attaching elastic to underwear.

407 – A three needle coverseam which is a variation of stitch 406. It is formed with 3 needle threads and one looper thread. It is stronger and more elastic and is also used for undergarments.

Overlock stitches:

Overlock stitches fall into class 500 and are also known as overedge, overlock, serge, overcast or Merrow stitches. They are typically used to create a stitch over the edge of cut fabric. Each of these stitches resembles a series of loops, and they are generally used for hemming and seaming, stitching over the edge of cut fabric to neaten the edges. The inner stitches are reinforced by thread around the edge of the fabric to ensure it is contained. Overlock machines usually trim the edges of the fabric as it is being stitched to prevent frayed or uneven edges. Overlock stitches are very common and often seen on the side seams of t-shirts and on other jersey or knitted fabric items.

Advantages: Secure seams. Good extension. Decorative. Prevent fraying on the edges of garments. Can be sewn quickly. Don’t unravel easily. Can usually run at high speeds.

Disadvantages: High thread consumption. The seams can be bulky.

503 - Also known as a 2-thread overedge stitch, this stitch type is created when the needle thread interlocks with the looper thread on the edge of the fabric. It is used to prevent the edges of material from fraying and is often used for blind hemming on t-shirts. It is not used for seaming as it is designed to collapse and flatten when a seam is loaded laterally.

504 - Also known as a 3-thread overlock stitch, this stitch is formed by 1 needle thread and 2 looper threads which interlock at the edge of the fabric. It used to stop the edges of fabric from fraying, and for joining 2 or more edges together, for example in the seaming of knit fabrics. It creates quite bulky seams which are not as secure as the 4-thread alternative.

512 - Also known as a 4-thread mock safety stitch and is created with 2 needle threads and 2 looper threads. In this stitch, the upper side of the stitch resembles the upper side of a true safety stitch (stitch type 516). It is used to create strong seams on the edges of fabric with very good extension. It has high thread consumption but creates a more secure seam than the 504 stitch.

514 - This overedge stitch is formed by 2 needle threads and 2 looper threads. This is known as four thread overedge (full cover). This is due to the top looper extending its thread to the left hand sewing needle whereas stitch type 512 only extends its upper looper thread to the right hand sewing needle. Then we have stitch type 515 which is class as the four-thread (safety-stitch) – formed by one row of stitch type 401 (chainstitch) and one row of 503 (two-thread overedge. It is a strong seam with high elasticity.

516 - Stitch type 516, or a 5 thread “full safety” stitch, is another combination stitch type. It is formed with 2 needle threads and 3 looper threads. This stitch type combines 401 chainstitch with 504 three thread overedge (overedge full safety stitch). The chainstitch (401) part is what holds the weight while the three-thread over-edge (504) element covers the edge of the material and provides additional seam security. It is used for joining panels where elasticity and seam security are important.


Coverstitches fall into class 600 and are also known as flatlock stitches or covering chain stitches. They are formed with multiple threads and are the most complicated of all stitch types with some having up to nine threads including four needles, looper and spreader threads! Coverstitches are usually used for hemming and are popular for making items such as sweatshirts, sportswear, and tshirts, as well as for attaching lace and elastic to knit fabric. They are basic coverseam stitch types with the addition of a top covering thread produced using a spreader device. This top cover element provides decoration and protection to reinforce the seam.

Advantages: Good for working with stretchy fabrics. Have high elasticity. Produce a professional finish on garments such as activewear and childrenswear. Secure. Produces a flat comfortable seam which doesn’t irritate skin.

Disadvantages: High thread consumption. Can require more skill to use the machines so training sometimes required.

602 –Also known as a twin needle coverseam stitch with top cover, this stitch is very similar to the 406, with the addition of a top covering thread. This is often used for attaching collars to knit garments, as it produces a neat top and bottom cover and flat seam. It is formed with 2 needle, 1 looper and 1 spreader thread. It is used as a decorative stitch on nightgowns and sweatshirts, for stitching the legs of athletic wear and straps on swimwear.

605- This stitch is also known as a three needle coverseam stitch with top cover. It is formed with five threads, three from the needles, one from the looper, and one top covering thread. It is often used for cut edge binding and attaching elastic. Seams which use this stitch have high elasticity, which makes it a good choice for stretchy garments. It can also be used to create decorative seams. Has a high seam elasticity and very high thread usage.

607 - This flatseam stitch is formed with 6 threads, four from the needles, one from the looper, and one top covering thread. This type of stitch has a higher thread consumption but produces flat, comfortable seams which can handle a lot of stretching and seam elongation.

Leave a comment

All comments are moderated before being published