Only a few days into the new year, Delta Air Lines has launched the first airfare hike of 2016, an increase of up to $4 per flight.
The hike, which Delta initiated Monday morning, was matched a few hours later by Southwest Airlines. American and United Airlines both matched the increase Tuesday morning.
In the past, fare hikes have typically been matched by most of the major carriers when Southwest, the nation's most popular domestic carrier, has gone along with an increase.
Rick Seaney, founder of the travel site Farecompare.com, said the increase was surprising, considering that nearly every major carrier has been collecting record profits recently because of low fuel costs.
"What the airlines are doing is what they've always done: probing consumers' appetite for travel by determining their pain-point on price," he said on his website.
The nation's 10 largest commercial carriers reported a net profit of $9.3 billion in the third quarter of 2015, up from $3.1 billion in the third quarter of 2014, according to the latest data reported by the U.S. Department of Transportation.
The most recent price increase will be added to nearly every type of flight, including short, medium and long-haul flights.
In 2015, various airlines initiated five fare hikes but only two were matched by the country's largest carriers, according to Farecompare.com.
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