AAII 2025–2026 Tax Guide: 2026 Tax-Planning Calendar
Key tax dates, deadlines and action items organized by quarter to help you stay on track with filing, payments and strategic planning throughout 2026.
Tax and financial planning are activities best pursued year-round. Although the timing of some activities is critical, you should review all tax considerations from the perspective of your specific needs and establish an individualized planning calendar.
If the last day for filing a return, paying tax or performing other activities falls on a Saturday, Sunday or legal holiday (in the District of Columbia), you generally have until the next day that is not a Saturday, Sunday or legal holiday to perform that act. Use the following list to remind yourself of important activities and dates.