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September 15 – Third Quarter Estimated Taxes Due

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September 15 – Third Quarter Estimated Taxes Due

September 15, 2025

In general, anyone who expects to owe $1,000 or more is required to pay quarterly estimates (unless their taxes are automatically deducted by an employer). Estimated tax deadlines are typically on April 15, June 15, September 15, and January 15 of the following year.

Why These Dates Matter

Who Why It Matters
Individuals (employed) File timely, avoid penalties, ensure refunds; know when to contribute to IRAs/RMDs.
Self-employed / Freelancers Estimated tax payments crucial to avoid underpayment penalties; extension can help finalize income and deductions—especially useful for retirement contributions or waiting on late-arriving documents.
Small businesses / LLCs Must manage both federal (income, payroll, estimated taxes) and state excise (B&O, sales) calendars—monthly, quarterly or annual. Missing WA DOR deadlines can result in steep penalties.
Payroll providers / employers Must issue W-2s and 1099s by January 31.
Retirees / account holders RMD requirement deadline is December 31.

Would you like help scheduling reminders, calculating an estimated amount, or setting up a withholding adjustment to cover this? Contact us today to get help with your taxes. Bellevue (206) 838-3800 — Duvall (425) 788-1544

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