China's top airlines are reporting a surge in interest among passengers wanting to pay extra to reserve preferred seats on both domestic and international flights.
Hainan Airlines Co Ltd became the first major Chinese carrier to charge extra for seat selection on long-haul flights in May 2013, and the option has now become so popular with passengers, the country's other top airlines have followed suit.
Mao Yi, head of public relations at Shanghai-based low-budget carrier Spring Airlines Co, said: "It may be a new phenomenon for Chinese commercial airlines to charge extra for a particular seat-but it is common industry practice globally, especially on budget airlines."
Spring Airlines started offering paid seats as far back as 2005, and over the years Mao said its most loyal customers have become used to paying extra for a more spacious or better-positioned seat.
Wang Zhenghua, Spring Airlines' founder and chairman, said: "It is only a matter of time before add-on products such as the seat selection services will account for a significant part of airline revenue."
Yu Nan, an industrial analyst from Haitong Securities Co, said: "The seats on the first row of the economy cabin, for instance, and those located near the emergency exit, are a lot more spacious than others.
"To charge more money to get one of the roomier seats is good business, and certainly helps bring in more revenue. I expect the service to become normal and more generally accepted."
Officials at Hainan Airlines, which also offers the booking option on its domestic services, said travelers can pay to book preferred seats by phone 48 hours before departure, and also some seats are available to reserve at counters, China National Radio reported.
At China Southern Airlines Co, meanwhile, a spokesman said: "We launched a paid-seat product on our official website in April this year. It is now available on 12 long-haul flights from Guangzhou to Australia, Europe and America."
China Southern's costs are between 300 yuan ($46) and 600 yuan for a prime seat on the first row or near an emergency exit, for instance.
"It is likely we will expand the seat selection service to more routes in the future, but there are still no plans for our domestic flights."
Shanghai-based China Eastern Airlines Corp Ltd started charging an average 500 yuan in January to choose seats on 12 of its international flights departing from Shanghai Pudong International Airport, but it too has no plans to offer the service domestically.
Beijing-based Air China Ltd also offers seat-booking services on some of its flights.
Wang Wen in Beijing contributed to the story.