Core Viewpoint - The article discusses the phenomenon of "tax rate jumping" in individual income tax, explaining how cumulative income can lead to higher tax rates due to reaching certain income thresholds [2][3]. Calculation of Individual Income Tax - The monthly individual income tax withholding amount is calculated based on the cumulative taxable income after deductions such as tax-exempt income, allowable expenses, and special deductions [3]. - The formula for calculating the current withholding tax amount is provided, emphasizing the importance of cumulative taxable income [3]. Reasons for "Tax Rate Jumping" - The implementation of the Individual Income Tax Law since January 1, 2019, has introduced an annual cumulative withholding method, which can result in higher tax rates as cumulative income increases [3]. - As cumulative income rises, the corresponding taxable income may reach higher tax brackets, leading to increased withholding tax amounts [3]. Critical Points for Tax Rate Jumping - There are six critical points for tax rate jumping: 36,000, 144,000, 300,000, 420,000, 660,000, and 960,000 [3]. - An example illustrates how an individual’s taxable income exceeding the first critical point results in a tax rate increase from 3% to 10%, leading to a higher withholding amount [3]. Year-End Tax Settlement - The article reassures that an increase in monthly withholding tax does not necessarily mean a higher total tax liability, as annual tax settlement can result in refunds or additional payments based on total income [3].

Group 1 - The article emphasizes the importance of timely tax declaration and reminders for individual income tax annual settlement, highlighting the deadlines for various submissions [5][7][11] - It outlines the process for setting up notification alerts in the personal income tax app for both Android and iOS systems, ensuring users do not miss important tax-related notifications [7][8] - The article provides a comprehensive list of reminders related to annual tax settlement, including special deductions and refund approvals, which are crucial for taxpayers to manage their tax obligations effectively [6][10][11] Group 2 - The article references the regulatory framework governing the annual tax settlement process, specifically the "Comprehensive Income Tax Settlement Management Measures" issued by the State Taxation Administration [7][11] - It discusses the significance of the personal income tax app in facilitating communication between taxpayers and tax authorities, particularly during the annual settlement period [5][9] - The article includes various scenarios and common issues related to special deductions, such as errors in spouse information for housing loan interest deductions, which taxpayers may encounter [11][13]