One card, two cities: Shanghai and HK unify transit payments
Shanghai and Hong Kong have integrated their public transportation payment systems, allowing seamless travel across the two cities.

With Hong Kong's MTR (Mass Transit Railway) joining the China T-union network, Shanghai residents can now use their Shanghai Public Transportation Card — whether physical or NFC cards — with a "China T-union" logo to tap and ride on Hong Kong's MTR system without purchasing tickets or exchanging currency.
Likewise, Hong Kong residents holding Octopus cards featuring the "China T-union" logo can now use them across Shanghai's public transportation network, including buses, metro, and ferries.
The China T-union network connects 336 cities and over 1,700 counties and districts across the Chinese mainland, streamlining inter-city travel across various modes of public transportation.

Hong Kong's inclusion, following Macao's integration into the network in December 2024, is expected to further enhance connectivity between the two special administrative regions and the Chinese mainland, while also fostering greater economic, cultural, and social exchanges.
Sources: Shanghai Observer, WeChat account of Shanghai Jiushi Group Co Ltd