About 99% of US Airways Group shareholders who voted Friday supported the merger with American's parent company, AMR Corp.
The vote was not surprising as it was US Airways that first proposed the merger after AMR Corp. filed for bankruptcy in 2011.
"This approval is a major milestone on our path to completing the merger, and we continue to make excellent progress overall thanks to the focused efforts of the dedicated representatives from both companies," said Doug Parker, chairman and chief executive of US Airways and incoming chief executive of the combined company.
The deal must still win approval from federal regulators and the U.S. Bankruptcy Court, which is overseeing the bankruptcy of AMR.
Under the proposed merger, the new company would be called American Airlines, with headquarters in the Dallas-Fort Worth area, nearly 950 planes and more than 100,000 workers.
The holders of more than 132 million shares voted Friday for the merger, with 257,757 shares voted against the union and 256,523 abstaining, according to US Airways.
The two airlines hope to complete the merger by September.
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