International visitors normally need a pre-arranged visa to enter China, but the country's newly expanded visa-free transit policies could allow some foreigners to enter China for up to six days without a visa, provided that their travel plans meet certain requirements.
The key rule here is that the visa-waiver scheme works for transits only, meaning that you're eligible only when you're entering from one country to travel through China before travelling on to another country.
There are three types of transits without a visa: the recent additions of the more accommodating 72 and 144 hours, and the conventional 24 hours.
Visa is not required for air, train, and ship passengers transiting in Chinese mainland for a stay of no more than 24 hours before heading for a third country or region.
Foreigners may be exempt from applying for visas under the following circumstances:
Hold connected passenger tickets;
Are in transit to a third country or region by an international aircraft, ship or train via China;
Will stay for not more than 24 hours in China without leaving the port of entry;
Will stay in the specific zones approved by the State Council within the prescribed time limit.