Sewing thread does expire eventually. Read more below to discover all the factors at play. Then take the simple test to see if your thread is still good!

Piecing and quilting thread can last 50+ years. But if the thread has not been stored correctly, that time length significantly goes down. Thread should be stored out of sunlight, as light can fade and weaken the fibers. If it was stored in a humid place, such as garage or attic for a period of time, it can get sticky or too thick from moisture intake. Similarly, if it was stored in a very dry or cold climate, the fibers can become brittle and break.

Generally, if you've bought thread or own thread that's covered in dust, it's a good sign that it hasn't been stored properly. Here are other important factors that clue you in to whether the thread is still good:

  • The quality of the thread (cheap versus a more high-quality thread)
  • The coating on the thread (a polyester thread won't deteriorate as quickly as a cotton one)
  • The materials of the spool (plastic spools help threads last longer than wood or Styrofoam ones)
  • Date it was made (older threads weren't made with the technology we have now, so they don't last as long as threads you buy new in the store today)

Here's a quick test you can perform on a spool to see if it's in good shape for your next quilt! Cut a 12"-piece of thread from the spool. Tie a knot in the center of the thread. Then gently pull the thread from both ends – if the thread breaks or tears in any way, it's too old to use.