Porter Airlines is extending its suspension of all flights by another four weeks until June 29 due to the COVID-19 pandemic.
The Toronto-based carrier stopped flying on March 21 as travel controls and rising public health concerns choked off demand.
"While there are many promising signs about how COVID-19 is being contained, it is also clear that border restrictions, government-imposed stay-at-home orders and bans on non-essential travel will remain in place for many regions through much of May and into June," Porter CEO Michael Deluce said in a release Monday.
His move follows WestJet's announcement last week to cancel some 18,000 flights between May 5 and June 4 due to record-low passenger numbers.
Air Canada cancelled all flights to the U.S. starting Monday after Ottawa extended its border closure with the United States by 30 days, with most international flights also halted and seat capacity down more than 90 per cent.
Air Transat and Sunwing Airlines Ltd. have cancelled all trips until May 31.
The International Air Transport Association predicts global revenues will fall by US$314 billion this year, or 55 per cent from 2019.
Like other Canadian airlines, Porter is offering two-year vouchers for flights it cancelled as a result of the virus, as well as waiving change and cancellation fees.
However, Porter is not advertising refund options for the suspended trips -- also in line with other carriers.
The approach stands in contrast to Porter's tariff -- a carrier's contract with its passengers -- that requires the company to offer the choice of a refund or alternative transportation to customers whose flights it has cancelled. Most Canadian airlines have comparable tariffs.
"Our policy is unchanged, offering travel credits for up to 24 months for flights cancelled due to COVID-19," the company said in an email.
The Canadian Transportation Agency said last week that the country's new passenger rights charter does not oblige airlines to refund customers for flights cancelled as a result of the pandemic, but reiterated customers' right to demand a refund based on the terms of the tariff.
A Porter spokesman said some laid-off employees would come back on the payroll to receive the federal wage subsidy but would remain "inactive until there is available work."
The company was not able to specify the number of workers who will return from layoffs.