Third quarterly estimated tax payment for self-employed and high-earning individuals.
The Q3 estimated tax payment covers July–September income and is due September 15. This is your third of four quarterly payments.
By mid-September, you have 75% of the year completed. This is the last opportunity to adjust your tax planning for the year. If your income is significantly higher than expected, you can increase your Q4 payment to cover additional tax liability. If income is lower, you can reduce Q4.
September is also a good time to consider year-end tax strategies: tax-loss harvesting in investment accounts, maximizing retirement contributions, considering charitable donations, or reviewing withholding for the following year.
Underpaying estimated taxes results in:
- Underpayment penalty accruing from Q3 through year-end
- Interest compounding quarterly
- Larger balance due on April 15 of next year
Add this deadline to your phone, calendar, or reminder app 2–3 weeks in advance to avoid last-minute stress.