I have a large assortment that I have acquired from thrift stores, yard sales, auctions... I just used some from a spool last week that had a price of $0.30 on it. So will let you figure out how old. LOL! I just do the strength test. If it isn't weak and easy to break, I use it. The only thread I have bought in years is my basic neutral color that I use for all my piecing.