Indoor tanning lotion does expire, and most brands have an expiration date printed on them. The lotion should be used within 1 year of purchase if no date is available.
Tanning lotion for indoors or outdoors can lose its effectiveness if it is not used by its expiration date. Using expired lotion can cause a poorly colored tan.
Sunscreens also have an expiration date, typically printed on the bottom of the bottle. If no date is visible, then the general rule is to use the sunscreen within 3 years of the date of purchase. Using the sunscreen after this time may reduce the amount of protection it offers.