Shenzhen’s tax authority and tech juggernaut Tencent jointly announced on March 18 that China’s first blockchain-based electronic ‘fapiao’ (invoice) has been issued at the Futian Station of the city’s metro network, according to a press release from Tencent Financial Technology.

The new service has been integrated into Shenzhen’s public transportation system, including the metro,taxis and airport shuttles. Starting Monday, passengers who use Tencent’s WeChat to pay for rides and file invoices, they can now obtain blockchain-based electronic invoice with just one click.

By replacing the traditional paper invoices, the blockchain-based e-invoice system is estimated to reduce the cost for the Shenzhen metro by nearly 400,000 yuan each year (about $59,577 ). As of 8:17 pm,March 18, more than 10,000 blockchain-backed e-invoices have been issued for the transport system.

In addition to Tencent that develops the underlying blockchain infrastructure, the Shenzhen Municipal Taxation Bureau has been trialing the blockchain-based e-invoicing system in cooperation with Hainan Golden Tech, a start up that offers invoice digitization and big data solutions. Shenzhen Metro Group,MTR Corporation (Shenzhen) and GRG Banking also contribute to the blockchain use case in public transportation.

“ Blockchain e-invoice is a new convenient and environSmentally friendly service that is integrated with the Shenzhen metro passenger QR codes, and further upgrades the smart travel experience for passengers,” said Song Lingyun, general manager of Tencent’s smart transit arm.

Shenzhen has become the pilot city for launching blockchain-based e-invoice as the nation’s first such invoice was issued to a local restaurant in August,2018. Since that time, the blockchain e-invoicing system has since rolled out to more than 1,000 merchants covering finance, retailing, catering and hotel industries. Data from Tencent shows the number of invoices has surpassed one million with a total value of 1.33 billion yuan.

According to Cai Yige, general manager of Tencent’s blockchain operations, blockchain e-invoices boast ‘whole-chain’ traceability and data immutability, which can reap significant efficiency gains by streamlining the invoice process and reducing over-reporting and false-reporting cases, while help form a highly mutual trust data sharing mechanism among tax authorities, companies and employees.