Our unit is in Beijing, so my social security is in Beijing, but I work in Tianjin. How to use medical insurance in Tianjin?

Ask the personnel department of your company to go to the social security department in Beijing for medical treatment in different places, and they will give you a form. You can fill in your personal information with the form, then take the form to the designated social security hospital in Tianjin and stamp it, and then mail the stamped form to the personnel department of Beijing company, who will help you to go to a different place for medical treatment. In the future, the money in your monthly medical insurance passbook will be directly remitted to your designated bank card in Tianjin (all my colleagues do are postal savings bank cards). You can also go to the hospital in Tianjin (you can choose to stamp it yourself). Expenses can be reimbursed in Beijing. But if you can, try to get the company to help you apply for social security in Tianjin. Because once one day you want to transfer Beijing's social security to Tianjin, you can only transfer the old-age insurance and pay part of it yourself. Most of the money the company gave you stayed in Beijing, which was a loss.

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