Earn 25,000 United or Continental miles after you sign up the Chase United MileagePlus Explorer Card. That's enough for a domestic round-trip ticket. The $95 annual fee is waived for the first year. You also get 5,000 miles for adding an authorized user and using your card within 2 months. Spend more than $25,000 in your first year, and you'll get an an additional 10,000 mile bonus. Card members get their first checked bag free on United or Continental flights, priority boarding, and 2 United Club daypasses annually, You earn 2 miles for every $1 spent with United or Continental, and 1 mile for every $1 spent elsewhere. Miles never expire.