However, pilots will not be paid during the month of October if that deal does not pass, according to a memorandum of understanding between United and the union representing its 13,000 pilots that was seen by Reuters.

"Our pilots are voting right now on a tentative agreement that, if approved, would avoid all pilot furloughs for at least nine months," United spokesman Frank Benenati said on Wednesday. He noted that the company continues to push for an extension of federal payroll support.

If lawmakers fail to agree to extend $25 billion in payroll aid for airlines this month, tens of thousands of employees are set to be furloughed on Oct. 1.

Delta Air Lines agreed with its pilots to delay furloughs until Nov. 1, the union said on Monday, but will continue to pay them in October even without an extension of $25 billion in payroll support for airlines.

(Reporting by Tracy Rucinski; Editing by Chris Reese and Tom Brown)