Depending on circumstances, some seeds can last several years (*3-5 on average*) before any noticeable change in germination. Gradually over time the germination rate (*number of seeds that sprout*) will decrease. The temperature seeds are exposed to is a significant factor in how long that will take, the colder the seeds can be stored the better.
**Good practices for seed storage**
- Dark location (pantry, basement or closet)
- Cool and dry (a fridge or freezer if you have the space)
- Airtight container (seal all bags securely, lids affixed)
Attached is an article that gives further details: https://www.trueleafmarket.com/blogs/articles/what-makes-a-seed-bad