A total of 1.05 million people made border crossings on Christmas Day.
Of these, 575,119 were departures, while 474,476 were arrivals, according to Immigration Department statistics.
The number of people coming into Hong Kong and leaving increased by 10.7 percent compared to 944,306 on Christmas Eve.
This was a 13.8-percent increase compared with Christmas Day last year.
A total of 92,592 people crossed the Hong Kong-Zhuhai-Macao Bridge, an increase of 26 percent in comparison to Christmas Eve.
Some 68,004 people traveled by the Guangzhou-Shenzhen-Hong Kong Express Rail Link on Christmas Day, marking a 4 percent increase from Christmas Eve.
Meanwhile, sales at shopping malls under Sun Hung Kai Properties increased over Christmas holidays.
Revenue at 15 of its malls reached HK$230 million between Friday and yesterday, marking a 13 percent rise when compared to the same period last year, the developer said.
"December is a high season for festive spending, and the retail industry has been stable," said Maureen Fung Sau-yim, the executive director of Sun Hung Kai Real Estate Agency.
"The employment market was also good, with many companies giving bonuses at the end of the year. Many people stayed in Hong Kong to celebrate the festival, which drove up consumer spending during Christmas."
Fung said APM mall in Kwun Tong attracted 1.9 million people over the six days, an increase of 15 percent from last year, while foot traffic at Tai Po Mega Mall hit 1.3 million, up 13 percent from the same period in 2017.