Legal analysis: There are two ways to declare personal income tax mortgage, namely, annual declaration and self-declaration. When the withholding agent declares, the unit shall pay the tax and reduce the tax every month. Self-declaration of annual comprehensive income means that the unit does not need to pay taxes or reduce taxes on its behalf, but needs to provide a unified social credit code in the process of information declaration, which can be obtained and filled in through online inquiry. Personal income tax and housing loan declaration methods are,

1. Declared by withholding agent.

2. Self-declaration of comprehensive annual income.

Select 1. Through the withholding agent's declaration, the unit where he works operates on his behalf, and the unit obtains the relevant information of his declaration.

Option 2. Self-declaration of comprehensive annual income. I should declare it myself. Personal property information is relatively confidential.

Article 9 of the Individual Income Tax Law of People's Republic of China (PRC) takes the income as the taxpayer and the unit or individual that pays the income as the withholding agent. If the taxpayer has a China citizenship number, the China citizenship number shall be used as the taxpayer identification number; If a taxpayer does not have a China citizenship number, the tax authorities shall issue a taxpayer identification number. When a withholding agent withholds tax, the taxpayer shall provide the withholding agent with the taxpayer identification number.

Legal basis: Article 14 of the Interim Measures for Special Additional Deduction of Individual Income Tax in People's Republic of China (PRC). Taxpayers and their spouses who use personal housing loans from commercial banks or housing accumulation funds to buy houses for themselves in China, the interest expenses incurred from the first housing loan shall be deducted according to the standard quota of 1 000 yuan per month in the year when the loan interest actually occurs, and the maximum deduction period shall not exceed 240 months.