Joining Taiwan Province nationality will lose the mainland nationality code.

Joining Taiwan Province nationality will not lose mainland nationality. Taiwan Province Province is the territory of China from beginning to end, and joining Taiwan Province Province will not lose mainland citizenship. Hong Kong, Macao and Taiwan residents' residence permit coding rules are the same. At present, the address code of Hong Kong resident ID card number is 8 10000, Macau 820000 and Taiwan Province 830000. The ID number is also 18 digits.