How old is too old to use thread? Recently took household items out of storage after 8 years. Storage wasn't as climate controled as we thought it would be so am concerned about the thread. Should I just pitch it?

pull some off the spool, and try to break it. Did it break easy? if so pitch it.

Some of it holds up just fine. Some doesn't. Do the test above and check it our before using.

sew a seam and try pulling it apart

Temperature shouldn't effect fabric or thread...it would be moisture and humidity that would have the negative effect....
I agree with what the others have said...I have some thread that is on wooden spools that my mother had that is just fine!

The only test I have ever heard of was pull it and see if it breaks .

That's the only way that I've been taught to test thread also!!

I also wanted to welcome you to this wonderful board from Florida!!

Eight years is a drop in the bucket. Some of mine is eight times that old and is still sound. The outside layer weakens first so you may want to "unpeel" it a bit before you try the snap test.

I pick up a lot of thread at garage/estate/auction sales & when it is older thread I check to see if it breaks & if it does I just keep unwinding it until I can't break it anymore. Usually once you get that first layer off the rest is good.

Very good info ladies!!!!