The flight attendants union at AirTran Airways said it has reached a tentative agreement on a new labor contract, which would give the flight attendants new terms for pay and benefits until they complete their transition to Southwest Airlines.

The next step is for flight attendants at AirTran to vote on the agreement.

Southwest, which acquired AirTran in 2011, said the deal gives flight attendants "rewards and incentives for increased productivity and perfect attendance, while remaining mindful of AirTran's low cost structure," according to a written statement from Southwest's vice president of cabin services Mike Hafner.

Meanwhile, the Association of Flight Attendants union called the negotiations “difficult.” In a written statement, the union did not boast about improvements reached in the deal.

The two sides had been in talks since February 2013 on a deal to “serve as a bridge” for AirTran flight attendants until they transition to Southwest. About 400 AirTran flight attendants have already shifted over to Southwest, and the process is expected to be complete by early 2015.

“Working in the limited time frame left for AirTran, it became clear it was time to make some difficult decisions, and bring these negotiations to a close…. Flight attendants will make the final decision through their vote.”

Some 1,700 flight attendants remain on the AirTran side. Southwest flight attendants are represented by the Transport Workers Union, which is in negotiations with Southwest on a new contract.