Visa Extension in mainland China

Usually, the extended time won't exceed the original duration of stay. So I cannot guarantee whether you can get a 90-day extension. But you can have a try. First, you may need to provide your passport, the completed application form, a recently-taken bareheaded color photo, registration form of temporary residence, as well as other requirements. Then, you can can apply for an extension 7 days before your current visa expires at the exit and entry administration of the local PSB.