Complimentary Upgrade Terms & Conditions

Availability:
Unlimited Complimentary Upgrades are subject to availability, may not be available on all flights or in all markets, and are not valid for travel to/from Hawaii, Transatlantic and Transpacific destinations. Complimentary Upgrades are not available on flights to/from South American cities that are serviced with our BusinessElite® product (i.e., Buenos Aires, Argentina; Rio de Janeiro and Sao Paulo, Brazil; Santiago, Chile; Lima, Peru; Caracas, Venezuela).

http://www.delta.com/skymiles/about_...ades/index.jsp