2. Open the personal income tax APP, find the option of "special additional deduction declaration" in the common business column on the homepage of the personal income tax APP, and click enter;
3. After entering the special additional deduction declaration page, select "Deduction Year" at the top of the page;
4. Select the additional special deduction information to be filled in, and click "Housing Loan Interest" to fill in;
5. Fill in my information according to the page prompts, such as mobile phone number, contact address, etc.
6. After completing the personal basic information, enter the mortgage information filling page. Taxpayers need to fill in the information according to their actual situation, choose the loan method, and then fill in the information such as mortgage interest according to the actual situation;
Legal basis: People's Republic of China (PRC) Tax Law.
Article 45 Tax authorities shall collect taxes, which shall have priority over unsecured claims, unless otherwise provided by law; Where the tax owed by the taxpayer occurs before the taxpayer mortgages or pledges his property or the taxpayer's property is retained, it shall be executed before the mortgage, pledge or retention. If the taxpayer fails to pay the tax and the administrative organ decides to impose a fine or confiscate the illegal income at the same time, the tax shall take precedence over the fine or confiscate the illegal income. The tax authorities shall regularly announce the taxes owed by taxpayers.
Article 46 If a taxpayer owes taxes and mortgages or pledges his property, he shall explain the tax arrears to the mortgagee and the pledgee. Mortgagees and pledgees may request the tax authorities to provide information about tax arrears.