It will come as no surprise to Canberrans flying over the Christmas period to visit family or for a summer holiday that the route between Sydney and the national capital is among the most commonly cancelled in the country.

The latest figures from the Infrastructure Department show 38 flights were cancelled on the Sydney-to-Canberra route in November, down from 43 flights in October.

And September was a particularly bad month to be flying from Sydney to the territory, with 59 flights not cleared for take-off.

According to the department, the Sydney-to-Canberra route had the second highest cancellation rate in the country last month, after flights from Dubbo to Sydney.

People flying the opposite way from Canberra to Sydney also did not have much luck last month, with 36 flights cancelled in November.

That is a combined total of 74 cancelled flights between the two cities in 30 days.

Most of the cancelled flights were courtesy of QantasLink, which was responsible for more than 60 per cent of cancellations between the cities last month.

But the airline has taken steps to improve reliability, resulting in a slight improvement in the cancellation rate last month compared to previous months.

Qantas said the company was expecting to see the decrease in cancellation rates continue for December.

"We're seeing improvements as a result of the recent adjustments we've made to our network and schedule, and our teams remain focused on ensuring this trend continues," QantasLink chief operating officer Jenny Chamberlain said.

Nationally, routes between Melbourne and Sydney had the highest number of flights cancelled — 133 last month alone — but due to the large volume of flights the cancellation rate remains fairly low at just about 2.7 per cent.

The cancellation rate for flights between Sydney and Canberra was 5.1 per cent in November.