1. Upgrade the "Personal Income Tax" App to the latest version, log in and improve personal information, especially real-name authentication and employment information. If the information is incomplete, it will not be calculated. 2. Open the "Personal Income Tax" App and click "Annual Calculation of Comprehensive Income". 3. Enter the interface of "Annual Settlement of Comprehensive Income" and click "Start to declare" to deduct personal income tax from mortgage. According to the latest Individual Income Tax Law of People's Republic of China (PRC), mortgage interest can be deducted from personal comprehensive income as a special additional deduction. Accurately speaking, the mortgage interest is taken as the deduction item, and the amount after deducting the mortgage interest and other deductions that meet the requirements is taken as the starting point for collecting personal income tax.

Personal income tax can be deducted from the mortgage. If taxpayers or their spouses use individual housing loans from commercial banks or housing accumulation funds alone or jointly to purchase housing for themselves or their spouses in China, the interest expenses incurred in 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.