Porter Airlines says its services are coming back online after a computer network outage caused dozens of flight delays and cancellations on Tuesday.

The outage affected the airline's website and call centre Tuesday evening, as well as passenger check-in.

About 40 departures and arrivals were cancelled or delayed.

Officials at Porter, which has its headquarters in Toronto, told CBC News that the cancellations are due to outages affecting their system provider, Navitaire, which manages bookings for several small low-budget airlines.

Navitaire is used by about 50 flight companies around the world, several of which are also experiencing problems.

Just after midnight, Porter tweeted that its services were coming back online, though six flights out of 200 that were scheduled for Wednesday were cancelled.

Porter spokesman Brad Cicero said the airline isn’t expecting much of a disruption for travellers on Wednesday morning.

“Everything returned to normal overnight and we’re in the process of moving people from flights that were cancelled yesterday to flights that are operating today," he told CBC News.

Porter is advising passengers to call 1-888-619-8622 on Wednesday morning to find out the status of their flights.

With files from The Canadian Press