Using United Club Passes After They Expire
Update: Some offers mentioned below are no longer available. View the current offers here.
Airlines aren't known for being especially generous when it comes to honoring expired perks, but I recently discovered one major exception to this rule: One-time passes for the United Club. These paper certificates are issued each year as a benefit of the United MileagePlus Explorer Card — as of 2015, Hyatt Diamond members (of which there are now many) are also entitled to two passes each year. Typically, passes expire at least a year after they're issued, but if you aren't able to use them before that date, they're not entirely worthless.
Currently, you can use an expired pass to enter a United Club with a $25 co-pay. Regular single-use passes run $50, so that's a pretty decent savings. Of course, a visit to the United Club may not be worth $25 to you, but with renovated lounges and improved food offerings, you can certainly get your money's worth with a longer layover or flight delay. Note that expired passes (plus the co-pay) must be redeemed within one year of the expiration date.
It's sometimes also possible to get a year (or more) of free access by taking advantage of a status match, and you can get access with the United MileagePlus Club card (which recently raised its annual fee to $450). You can also get access by purchasing a full United Club membership, but unless you have elite status, that'll run you a whopping $550 each year (plus a $50 initiation fee).