Kara from Snellville, Ga writes
The Seresto Dog Flea and Tick Collar does not have an expiration date as long as it has remained in its original container and stored in cool/room temperature conditions. Once the collar has been opened placed on your animal, it will last 8 months according to the manufacturer. You may contact Bayer Animal Health at 800-255-6517 for more questions on their product.
Answer last updated on: 03/18/2016