How long can I keep unused canning lids before they are unsafe to use?
Unused lids will work well for at least five years from the date of manufacture. Older lids may fail to seal. Try to buy only the quantity of canning lids you can use in one year. Examine lids carefully before you use them. Don't use old, dented or deformed lids or lids with gaps or defects in the colored sealing gasket.
Barbara Willenberg, Nutritional
Sciences, University of Missouri-Columbia
Last update: Tuesday, May 05, 2009