How about social security in Guangzhou and Shenzhen?

The social security card in Shenzhen can be used in Guangzhou.

Steps to transfer social security across provinces:

1. Apply for social security payment voucher in Shenzhen insured institution (ID card, social security card and a copy are required);

2. Submit payment vouchers to the insured institutions in Guangzhou, and go through the application procedures for social security transfer;

3. Guangzhou social security agency and Shenzhen social security agency negotiate to handle the transfer, and the processing period is 45 working days.

Further reading: How to buy insurance, which is good, and teach you how to avoid these "pits" of insurance.