Southwest Airlines and Coca-Cola announced the Atlanta-based beverage company’s Vitaminwater brand will be offered on Southwest flights as a premium drink option. Terms of the deal were not disclosed.

Southwest also announced a sweepstakes to give away a year’s worth of Vitaminwater and travel on the carrier. Contest entry ends May 31.

Dallas-based Southwest acquired AirTran in 2011 and started its own flights to Hartsfield-Jackson International Airport last year. AirTran also has served Vitaminwater and a variety of other Coca-Cola products. Southwest will charge $3 for Vitaminwater.

Southwest is gradually replacing AirTran’s routes with its own. AirTran is the second-largest carrier serving Atlanta behind Atlanta-based Delta Air Lines.