Common Q&A for employment in Great Bay Area
Q: Do I need a work permit for employment in Mainland?
A: No, the State Council has confirmed the abolition of 11 administrative licences which includes approvals for work permits for employment in Mainland for residents from Taiwan, Hong Kong and Macao.
Source form: The GuoFa  No.28 ("the Circular") published on 28 July 2018, the State Council has confirmed the abolition of 11 administrative licences ("the abolishment").
Q: As a Hong Kong resident, how can I apply for the residence permit in Mainland?
A: Taiwan, Hong Kong and Macao residents who
(1) Have stayed in the Mainland for more than six months and
(2) Have a stable job; stable residence or continuing studies in the Mainland
That resident will be able to apply for residence permits in order to enhance their access to basic social welfare and services, for instance, in the areas of education, entrepreneurship, employment and living aspects, in the Mainland.
Source from: Circular of the General Office of the State Council on Issuing the Measures for Applying for and Issuing Residence Permits for Hong Kong, Macao and Taiwan Residents (GuoBanFa  No.81) 6 August 2018
Q: How much tax I am going to pay while working in Mainland?
A: If an individual without domicile stays in the Mainland China for
(1) 183 days or more in a year and*
(2) In the preceding six consecutive years the individual stays less than 183 days any one year or leaves the Mainland China for more than 30 days in one occasion*
The individual's overseas-sourced income will be exempted from Individual Income Tax (“IIT”)
Source from: Public Notice Regarding Criteria for Determining Days of Residence of Individuals without Domicile within the Mainland China (Public Notice  No.34)