Sunscreens definitely have an expiry date. The expiry date may be 2 or 3 years from the day you purchased it, but always check the bottle. How can you tell if the sunscreen ingredients have gone bad? Try spreading some on your skin – does it seem to thin, too thick, or too clumpy? Has it developed a gritty texture? If your sunscreen seems “off” in texture, it may be a good idea to throw out that bottle and purchase a new one.