Chinese embassies and consulates general do not extend the validity of an issued visa. If you already entered China and you want to spend more time in China, you can extend your visa within China.
Extending a Chinese visa is usually not so difficult, although prices, waiting times, and rules differ from region to region.
You are advised not to overstay the duration of your visa or fail to apply for an extension before your visa expires as you risk being heavily fined and have your travel plans disrupted.
The visa extension application should be submitted at least 7 days before the expiration date of the visa.
If you apply too late, you may overstay and are subject to a fine and possible deportation.
Once your visa is extended, the new dates start from the day you receive your new visa – NOT from the day your old visa was going to end.
You must go to the Public Security Bureau (PSB) Exit and Entry Administration office, situated in all larger towns and cities of China. In normal cases, you should submit the application in person.
In case, the staff cannot speak English, you are recommended to take a Chinese friend with you if you can.
Visitors who want their visa to be extended should provide the following evidential materials
The length of the extension depends on the type of visa and multiple entry visas cannot be extended.
Normally the extension of your stay can not exceed your current visa stay period.
You can extend your visa once or twice. This depends on the duration of your original visa. Your total extensions on any one entry to China cannot exceed the length of your original permitted stay. If you have a 30-day visa, you can extend for a maximum of another 30 days. If you have a 60-day visa, you can extend a second time.
The price is 160 yuan for nationals of most countries. For some countries, the price may differ. US citizens need to pay 760 yuan for an extension while UK citizens need 469 yuan.
Usually, the PSB will decide whether to grant the visa extension within 7 working days, upon the acceptance of all application documents.
If you have overstayed your visa, there are different levels of punishment based on the length of overstay, from penalty 500 RMB per day to detention for a period of 5 to 15 days.
With that laid out, if you are indeed in an overstaying situation then you should report to the local police station as soon as possible, pay the penalty, and then apply for an exit permit in order to be able to leave the country.