When you open a bank account in Hong Kong, the application will ask for a TIN. TIN stands for Tax Identification Number.
In Hong Kong, an individual's TIN is the HKID number
In Hong Kong, an individual's TIN is the HKID number. The first letter of the alphabet is included. The parentheses at the end of the number are excluded.
For example, if the HKID number is M012345(6), the TIN will be M0123456. The TIN of a Hong Kong corporation is the BR number (Commercial Registration Number). The first eight digits are the TIN.
If your BR number is 12345678-999-99-99-9, then 12345678 is your TIN.
What about Japan? The TIN for individuals in Japan is My Number. When a Japanese resident opens a bank account overseas, he or she enters his or her My Number in the TIN field of the account opening application.
The TIN of a Japanese corporation is its corporate number. The number can be checked by anyone at the National Tax Agency's Corporate Number Publication Site.
Below is a link to the OECD. You can see which number to look at for each country's TIN.
OECD web site