Southwest Airlines will start assigning seats to passengers, ending its longstanding policy of allowing passengers to pick their seats once they have boarded, the airline said on Thursday.

The new procedure will be implemented to increase revenue and in response to feedback from customers, 80 percent of whom report preferring an assigned seat, Southwest said.

“This is the right choice — at the right time — for our customers, our people and our shareholders,” said Bob Jordan, the president and chief executive of Southwest. Even though the airline has been known for its unique seating model for more than 50 years, preferences have evolved, with more customers taking longer flights where they prefer a seat assignment, the statement said. The new policy was reported earlier by The Wall Street Journal.

The changes bring Southwest, which for years has distinguished itself by offering low prices and a simple business approach, more in line with conventional airlines like American Airlines and United Airlines.

Airlines have tinkered with ways to make boarding more efficient since they started charging for checked bags 15 years ago. That change led more people to bring carry-on luggage and increased demand for early boarding to compete for space in overhead bins.

United Airlines last year updated its boarding process so that passengers in economy with window seats and exit rows would board the plane before people in the middle and aisle seats. The change, which affected domestic flights and some international ones, was expected to cut up to two minutes from boarding time on each flight, according to an internal memo shared with The New York Times in October.