How long do black olives last once opened? I opened a can of sliced black olives for my pizza and only used half. I put the leftovers into a sealed container with the liquid and put it in the fridge. Under those conditions how long will the olives last? Is there a better way to store leftover olives?
Olives are basically cured in salt, so they will last a very long time.  They will last even longer if kept in an air-sealed container in a refrigerator.  They will last even longer than that if kept in a salty brine which covers them with liquid and minimizes exposure to air.