United Continental Holdings Inc. on Tuesday raised its fourth-quarter passenger unit revenue guidance to an expected decline of between 1.25 percent and 1.75 percent from 3 percent to 4 percent, pushing up its expected pre-tax profit margin compared to the fourth quarter of 2015.

United, the No. 3 U.S. airline by passenger traffic, credited its improved outlook to strengthened last-minute bookings and ticket yields in November and December.

Business demand was stronger than expected in the two weeks leading up to Christmas, the company said in an SEC filing posted to its website, and the winter holidays brought better-than-expected demand for leisure travel.

The carrier now expects its profit margin to be between 9.25 percent and 9.75 percent, up from its earlier prediction of between 7.5 percent and 8.5 percent.

United shares were up in after-hours trading at US$75.48 from a closing price of US$73.66.