If you’ve ever inherited a box of thread from your mom, grandma, or stumbled across a great-looking spool at an estate sale, you may have asked yourself: Does thread go bad?

The short answer is yes—thread doesn’t exactly have an expiration date, but it does have a lifespan. How long it lasts depends greatly on how it’s stored. In her recent Tipsy Tuesday episode, Gudrun shared some eye-opening tips on keeping your thread strong, reliable, and ready for your next quilting project.

How Long Different Threads Last

Each fiber type has its own lifespan when stored properly:

• Cotton thread: About 5–10 years (up to 12 with great storage).
  
  

• Polyester thread: 20–50 years—this one’s the winner for durability.
  
  

• Silk thread: 10–20 years, but requires special care.
  
  

• Rayon thread: 5–8 years, and particularly sensitive to storage conditions.
  
  

Natural fibers like cotton and silk are more prone to drying out, fading, or breaking down than synthetic ones.

Signs Your Thread Has Gone Bad

Not sure if that spool in your stash is still usable? Do a quick check:

• Breaks easily when tugged → fibers are dried out.
  
  

• Looks faded or dusty → UV damage and dust weaken the thread.
  
  

• Feels rough or stiff → fiber structure has deteriorated.
  
  

• Snaps during machine quilting → the tension integrity is compromised.
  
  

• Shreds or fuzzes easily → the ply or twist is breaking down.
  
  

• Mildew or sticky residue → it’s been stored in high humidity.
  
  

Unfortunately, once thread is past its prime, there’s no way to “rehydrate” it. It’s best to retire it rather than risk it in a quilt you’ve worked hard on.

How to Store Thread Properly

The way you store your thread makes all the difference:

• Keep it cool, dry, and dark – Light and dust are thread’s biggest enemies.
  
  

• Avoid open racks near windows – as pretty as they look, they invite UV damage and dust.
  
  

• Skip the attic or basement – extreme temperature and humidity swings will shorten thread life.
  
  

• Use airtight containers if humidity is an issue. Toss in a silica gel pack for extra protection.
  
  

• Be mindful with silk – don’t store it in wooden drawers (tannins in wood can damage it).
  
  

Pro tip: If you buy thread assortments that come in plastic cases, save the boxes! They’re perfect for ongoing storage.

The Tug Test

Not sure if your thread is still strong enough? Try Gudrun’s tug test:

1. Pull about 18 inches of thread.
   
   

2. Hold it taut between your hands.
   
   

3. Apply moderate pressure.
   
   

If it snaps easily, feels stretchy, or gummy—it’s time to let it go.

A Note on Secondhand Thread

Estate sale finds may be tempting, but beware: you don’t know how old the thread is or how it was stored. Even if it looks fine, it may already be past its lifespan. Better to invest in fresh thread than risk your quilt falling apart.

Wrapping It Up

Thread may not come with an expiration date, but with good storage habits, you can get the most out of every spool. Keep it out of light and dust, control humidity, and check it before stitching. With these simple practices, your thread will stay strong and ready to support your quilting for years to come.

✨ Quilter’s Tip: Think of thread like fabric—it deserves the same thoughtful storage to keep it beautiful and functional!