If you've noticed that Canadian airliners seem to be flying fuller than ever these days, you'd be right.

On Tuesday, both Air Canada and WestJet reported record load factors for January — traditionally a slow month for air travel.

Air Canada said 77.9 per cent of its available seats on its mainline carrier and Jazz were filled with paying passengers last month. That's a record for the month of January.

Air Canada and Jazz together boosted capacity by 3.7 per cent last month. Traffic, as measured in revenue passenger miles, rose slightly more.

"System-wide traffic, on a combined basis, increased 3.8 per cent from the previous year, outpacing capacity growth," Air Canada CEO Montie Brewer said.

Similarly, WestJet said its January load factor was a record 76.2 per cent. WestJet's fuller planes came despite a 15.7 per cent increase in capacity.   

"Our strategy of seasonally adjusting the deployment of our capacity continues to produce improved year-over-year results," WestJet CEO Sean Durfy said.

Despite the strong traffic reports, shares of WestJet fell 32 cents to $17.99 on the TSX. Air Canada's Class A shares slipped 33 cents to $7.89. Air Canada presents its fourth-quarter and full-year financial results on Thursday.