How To Choose The Right Thread For Your Sewing Project


Thread is a fundamental ingredient for any sewing project. Whether by machine or by hand, we can't sew without thread! How many times, though, have you found yourself at the checkout counter of your favorite fabric store, uttering, "Oh, yes, I need thread!?" And you simply grab a spool from the nearest rack, in a matching color of course, but without much thought as to what type or brand might produce the best results for your project. I know I'm guilty.

Does it really matter which thread you use? Yes, it does. Thread comes in a wide variety of fibers, sizes and quality levels.

My Old Thread Collection

My Old Thread Collection

In order for your thread to produce strong and durable seams without being obtrusive on your fabric, you need to choose it wisely. Let's outline the most commonly used types of thread and talk about why thread quality is important, allowing your sewing machine to weigh in. We'll touch briefly on a few specialty threads and then share some helpful tips about choosing the right thread for your sewing project.


Cotton Thread
Cotton thread (in a medium thickness, size 50) is best suited for projects using lightweight to medium-weight, natural woven fabrics such as cotton, linen and rayon. Most cotton thread is mercerized - a finishing process that leaves the thread smooth and lustrous. Cotton thread is softer than polyester. It also has very little "give" (elasticity) and will ensure your project, such as a pieced quilt, holds it shape. This said, it is not a good choice for stretchy fabrics!  

Cotton thread is a favorite among quilters who are sewing with high-quality quilting fabric. The 50-weigh in a neutral color is ideal for piecing, appliqué and binding, whereas a heavier 28-weight is best for quilting. It must withstand the stress of pulling and stretching. Quilting cotton is available coated, allowing the thread to pass through quilt fabric and batting with ease, or you can wax your thread as you go. ***Only use coated quilting cotton for hand quilting, as the coating will gum up your sewing machine.



Polyester Thread
Polyester thread is truly an all-purpose thread and is suitable for most sewing projects. It is a good choice for woven synthetics, knits and fabrics with stretch in them because it has some "give" to it and won't break easily. Most polyester threads are treated with a wax or silicone coating, which enables the thread to slide through fabric easily. Polyester thread is widely available and offered in a vast spectrum of colors, making fabric coordination a breeze.

Cotton Covered Polyester Thread
Cotton covered polyester is an all-purpose thread combining the strength and elasticity of a polyester core with an exterior wrapping of cotton filament for durability and heat resistance. If your fabric requires high heat for pressing, this is a good thread variety to use. Blended threads are well suited for nearly all fabrics, including natural or synthetic, wovens or knits. 

Silk Thread
Pure silk thread is made from natural fibers and is recognized for its beauty and durability. It is very fine and comes in a variety of weights and colors. Silk thread has elasticity and is well suited for thin delicate fabrics such as those used in lingerie. Use it when sewing with silk fabrics and wool. It is also an excellent choice for basting, as it won't leave imprint "holes" in your fabric once it is removed. Silk thread is a popular choice for hand and machine appliqué projects because the thread "melts" into your fabric, making your stitches nearly invisible.
**Do not confuse pure silk thread with "silk finish" cotton thread, a soft and lustrous top quality sewing thread made of double-mercerized 100% cotton. This thread has low shrinkage, provides seam elasticity, is exceptionally colorfast and safe to iron.




Heavy-duty Thread
Heavy-duty threads are more coarse, usually a size 40 or thicker, and stronger than all-purpose threads. They can be cotton, polyester and cotton/poly blends. Not suited for most garment construction, this type of thread is a great choice when using upholstery-weight fabrics for home decorating projects such as couch cushions or window shades. It is also a great choice for heavy denim projects and items such as backpacks where a finer thread will break. 

Button and Craft Thread
Button and craft thread is exceptionally strong and thicker than all-purpose threads.  It is most commonly used to sew on buttons by hand. It is also used for top stitching and soft sculpture sewing when a strong thread is needed. Don't be tempted to use it for regular sewing projects, even when you think a stronger thread is needed. A thread too thick for your project will appear obtrusive. 

Invisible Thread
Invisible thread is intended for just that purpose - to be invisible! No longer compared to "fishing line," today's invisible thread is soft and light. It is available in polyester or nylon and comes in different colorations and sheen levels. It is commonly used for sewing garment labels, multi-colored bindings, tapes and patches. Also a favorite for machine quilting, it allows the sewer to span multi-colored piecework without changing colors. 

Nylon Thread
Nylon thread is a synthetic fiber appreciated for its strength and flexibility. This thread is lightweight, smooth and suitable for light to medium weight synthetic fabrics such as nylon tricot, suede cloth, faux fur and fleece. A nylon seam will "last forever."

Wool Thread
Wool thread is most often used for embroidery. For sewing projects, it works best with heavy fabrics such as wool or canvas. 

Metallic Thread
Metallic threads are used to create exciting needlework and crafts with decorative stitching. 

Hand-Me-Downs From My Mom

Hand-Me-Downs From My Mom

Bobbin Thread
For most sewing projects, we use the same thread in our bobbins as we do in the upper threading of  our sewing machines. So what is "bobbin thread" and why would I use it? Bobbin thread is a thin, lightweight sewing thread and it can be nearly as strong as regular sewing thread, depending on the quality. It is available in cotton, spun poly (cotton-wrapped polyester) and filament polyester.

Four common uses for bobbin thread include: 

  • Machine Embroidery - Using a thin thread in your bobbin allows the back side of the embroidery stitches to be less dense than the front, especially on lightweight fabrics. This keeps your embroidery design less rigid and your fabric more pliable.
  • Machine Basting - Using a thin, delicate thread creates less impact on your seam and allows you to leave the basting thread, rather than removing it.
  • Sewing very fine fabrics - A lighter weight thread will be more invisible.
  • Hems - Bobbin thread is commonly used for hemming, providing a smooth lightweight finish.


I love a bargain. Who doesn't? But when it comes to sewing, I want a quality finished product and the best way to achieve that is to use quality components. Your sewing machine would agree with me. 

Among other characteristics, better quality threads are made of long, tightly woven fibers while economical ones have short, loose, stray  fibers - fibers that can get stuck in your fabric and in your sewing machine while you sew. You can't see these loose fibers with the naked eye but I can assure you they are there. These little "strays," we'll call them,  rub against the thread, leaving it weak and subject to breakage, both while you're sewing and later in the seam itself. These little fibers also clog your sewing machine's tension disks - the little devices that control the pressure as your upper thread travels through your machine - and affect your machine's ability to maintain an evenly formed stitch.

There is nothing more frustrating than broken thread, skipped stitches and uneven tension. Choosing quality thread will greatly reduce the negative affects of stray fibers, allowing your machine to maintain even thread tension and eliminating weakness and breakage.

My Favorite Spools! - A Thrift Store Find/Christmas Gift from Bailey 

My Favorite Spools! - A Thrift Store Find/Christmas Gift from Bailey 


  • Quality Matters - Choose the best thread you can afford.
  • Understand what type of fabric you will be using for your project before you select a thread. Your thread type should blend with the properties of your fabric, (fiber, weight and weave). For example, use a thread with "give" in it for a stretch knit. Many sewers use only cotton thread on cotton fabric, synthetic threads on synthetic fabrics.
  • Your pattern or tutorial may recommend a specific thread type for suggested fabrics. Try and match this recommendation whenever possible.
  • The higher the number, the finer the thread is. Sometimes letters are used to indicate size; A is a fine thread while D is a heavy thread.
  • Be sure to use the right needle when using specialty threads and adjust your tension accordingly if sewing on a machine. Also check to see if the thread you are using is suitable for machine use. Some are not, like hand quilting specialty threads.
  • Choosing the color for your thread is a subjective decision: match the fabric or use a contrasting color? It's your choice!  For solid fabrics, the vast majority will select a color that is the closest match. Most print fabrics have a predominate or background color and this color is chosen. Either way, if you cannot find the exact color, choose one slightly darker; a lighter color will be more noticeable.
  • Use these same principles when selecting thread for your serger. Use only quality serger thread! It is finer and does not produce as much lint and dust as regular thread. Serger thread is specially wound and glides quickly, preventing knots.
  • Your thread ages! Make sure that spool of thread kicking around in the bottom of your sewing basket is still good! See if a strand of it feels smooth or if you can break it. If it feels lumpy or breaks easily, throw it away.