Film Has An Expiration Date
All film should ideally be used and developed before the “develop by” date on the box it came in. This provides the best results. Film can be left inside the camera until that date.
Film Can Last For Decades
Film has a remarkably long life, if it is stored properly. If kept cool and dry, some unused film can last for decades. If you want the film inside your camera to hold its quality over time, keep the camera in a cool, dry place (not over 70 degrees Fahrenheit).
Bottom Line
Using film as quickly as possible, and before the expiration date, will ensure optimal results. However, if you find old, undeveloped film, don’t fret (unless it’s been in your hot attic): use and develop it as soon as possible.