How long do cigarettes last unopened in a fridge?

Unopened they can last a few months. In the fridge even longer, probably 6-12 months. Opened, they will only last 4-7 days before they start to tast funny and go stale if you dont put them in a fridge. You can still smoke them but it wont taste as fresh as the first few you had from the pack.

Stay Lit!