It can expire One of the strictest Delta Companion Certificate rules is that travel for any companion pass must be booked and completed by the expiration date listed on the certificate. Note that its validity is not based on the calendar year.

Yes, almost all airline companion tickets (such as those from Delta, Southwest, or British Airways) have strict expiration dates, typically aligned with your credit card anniversary or the date of issuance. For the Southwest Companion Pass, the benefit is valid for the remainder of the year in which you earned it plus the entire following calendar year. Once that period ends, the "ticket" or privilege disappears unless you re-qualify. For Delta Companion Certificates (Amex Platinum/Delta Reserve), they usually expire 12 months from the date they are deposited into your SkyMiles account. It is crucial to note that the travel must be completed by the expiration date, not just booked. In 2026, most airlines do not offer extensions for unused certificates, even for medical reasons, as they are considered "perks" rather than paid assets. Always check the "Certificates and Vouchers" section of your loyalty profile to track the exact "use-by" date and avoid losing a benefit that can be worth hundreds or even thousands of dollars.