Pecans can last from two months to two years. How long they last depends on the storage method and the temperature. Shelling the pecans gives them a shorter shelf life.
Store pecans in clean, tightly sealed dry bags or jars; nuts easily absorb strong smells. Small pieces spoil more quickly, so buy pecan halves or whole, uncracked nuts. Packaged pecans often have a use-by date.
Pecans in the shell last for up to two years when frozen in airtight containers. Frozen shelled pecans should be used within 18 months. Refrigeration preserves pecans for about two months. Storing nuts at room temperature is the least effective method and is not recommended.