Shanghai's relaxed visa policies paid dividends in 2017, with the city's ports handling a record number of passenger visits, according to the latest official data.

People entered or exited China more than 43.7 million times via the eastern metropolis, up from 42.4 million in 2016 and 37.5 million in 2015, the Shanghai General Station of Immigration Inspection said on Monday.

The vast majority - 35.6 million - traveled through Pudong International Airport.

Combined, the number of overseas passengers who passed through Pudong and Shanghai's other international airport, Hongqiao, accounted for nearly 28 percent of the national total in 2017, according to the Shanghai Transport Commission.

The immigration station said people traveled through the city's cruise liner port more than 4 million times, making it the busiest in Asia in terms of traveler numbers and the fourth-largest in the world.

Authorities have attributed the increase in visitors to the six-day transit visa for nationals from 53 countries and regions, which started in January 2016, as well as the city government's decision in October 2016 to allow tourists on foreign cruise tours to stay for 15 days without a visa.

Statistics from the city government show 83,000 transit visas were issued in 2017, up by 135 percent year-on-year, while 8,500 entry permits were given to cruise passengers, up by 40 percent.

"The visa policies are expected to attract more foreign tourists to Shanghai and neighboring regions, contributing to the economy and tourism development in the Yangtze River Delta," said Wang Meng, an information officer with the immigration inspection station.

Shanghai was the first city in China to introduce a cross-region transit visa. It permits foreign visitors to travel through the entire Yangtze River Delta.

The waiver for cruise passengers, available for groups of at least two on tours arranged by registered Chinese travel agencies, allows tourists to explore the country's coastal regions and even as far as Beijing.

The policy was devised after authorities noticed that the number of visitors entering and exiting the cruise liner port grew 35 percent year-on-year in 2015, but the number of foreign passengers remained almost the same.

"We believe the policy will inspire cruise operators to design new products with more stops at Chinese ports that offer foreign tour groups a variety of options on the cities they want to visit," a spokesman for the immigration inspection station told thepaper.cn in September 2016.

To save time for air passengers, Pudong and Hongqiao airports also began replacing manned immigration desks with electronic channels in February 2016. There are now 113 e-channels across both airports.

"Passengers just need to scan their boarding passes, passports, scan their fingerprints and have a portrait picture taken at the checkpoint and the gate will open," Wang said. "It takes only 10 seconds, compared with about 45 minutes at a manual desks."