United Airlines is offering a free Treo 650 smartphone to those Mileage Plus members who purchase a United ticket for $500 or more.

Through Dec. 31, 2005, members have the opportunity to receive a free Treo 650 smartphone. The phones offer a compact mobile unit with email, an organizer, messaging, access to the Internet, a camera and a MP3 player. The offer requires customers to activate the Treo 650 on a qualified Cingular Wireless data and voice plan with a two-year agreement. The plans run between about $50 and $100 a month.

To register for the offer, visit united.com/treo. Once registered, members should complete a paid, qualifying roundtrip or one-way flight on United, United Express or Ted before Jan. 6, 2006 at a value of $500 or more.