BEIJING — Beijing and the neighboring Tianjin municipality have launched a service that enables metro passengers to use the same QR code to pay for tickets in both cities.

It is common in China for subway passengers to pay using QR codes, which are usually scanned at ticket gates. However, codes are often on different apps developed in different cities and cannot be used interchangeably.

The service, effective on Feb 6, allows QR codes on the latest apps in Beijing and Tianjin to be accepted in the subway systems of both cities.

Beijing's transport authorities have noted significant passenger flows between the two cities and said that the new payment method is expected to improve the subway experience for passengers and help in promoting the cities' integrated development.

Beijing is expected to expand the metro payment method to more Chinese cities this year, including Shijiazhuang, capital of the neighboring Hebei province, and Guangzhou, according to authorities.