Alaska Air Group Inc. said it lost $19.2 million, or 53 cents per share in the first quarter and added that it will begin charging passengers $15 for their first checked bag.

The first-quarter loss compares with a loss of $27.3 million, or a loss of $1.01 a share a year earlier.

In the latest quarter, the Seattle-based company (NYSE: ALK) reported a one-time mark-to-market fuel hedge gain of $10 million. Without one-time items, the company reported a loss of $25.4 million, or a loss of 70 cents per share. Analysts polled by Thomson Reuters First Call expected a loss of 49 cents a share.

“While our first quarter financial results improved over last year due to a significant decline in fuel cost, we’re disappointed to report a loss for the quarter. To minimize the impact of the steep decline in air travel demand, we have reduced our schedules, reallocated capacity and taken fare actions. We are responding to the continued economic uncertainty by maintaining a healthy level of liquidity, retiming some capital expenditures, controlling costs, reducing capacity and actively pursuing revenue opportunities,” said Bill Ayer, Alaska Air Group’s chairman and CEO, in a statement.

One of the revenue opportunities the airline will institute effective July 7 is to begin charging passengers $15 for their first checked bag.

Alaska was one of the last U.S. airlines to begin charging passengers for checking luggage. The airline said it will offer a “bag guarantee,” which will guarantee that a bag will be at baggage claim within 25 minutes after a passenger’s plane parks at the gate, or the passenger will receive $25 or 2,500 of the airline’s mileage plan miles.

First Class Alaska MVP and MPV Gold mileage plan members will be exempt from the baggage fee, Alaska said.

Alaska Air Group’s Horizon Air is the largest and Alaska Airlines is the third largest commercial-passenger airline at Portland International Airport, according to the Portland Business Journal’s 2009 Book of Lists.