September 2025 Tax Milestones: Key Actions and Preparation

As September 2025 rolls around, it's imperative to stay on top of crucial tax obligations, including tip reporting and making estimated tax payments. In this detailed guide, we explore safe harbor regulations, penalty avoidance strategies, and essential preparation tips for 2026.

2025 Fall and 2026 Tax Strategies

Our team at Thomas Hawbaker CPA PLLC stands ready to assist you with personalized tax planning. Schedule a consultation with us to ensure your strategy aligns with both current demands and future goals. Here's what you need to focus on this September:

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September 10 - Report Tips to Employer

Employees earning tips must report any amount over $20 received during August to their employer using IRS Form 4070 by September 10. Compliance ensures proper withholding of FICA and income taxes. If your wages do not suffice for the withholdings, your employer will report the shortfall in Box 8 of your W-2. You'll need to cover this when filing your annual tax return.

September 15 - Estimated Tax Payment Due

The third installment for 2025 individual estimated taxes is due, and it’s crucial to understand our "pay-as-you-earn" system. The government aids this process through:

  • Employee payroll withholding;
  • Retiree pension withholding; and
  • Estimated payments for self-employed individuals or other income earners outside standard withholding.
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Taxpayers missing the minimum safe harbor prepayment risk facing an underpayment penalty, calculated as the federal short-term rate plus 3%. Avoid penalties by:

  • Ensuring your payments cover at least 90% of the current year's tax;
  • Matching or exceeding 100% (or 110% for high-income earners) of last year's tax.

Example: If your tax totals $10,000 and prepayments are $5,600, the $4,400 shortfall could incur a penalty unless you meet the prior year’s 110% safe harbor. Assuming last year's tax was $5,000, a prepayment of $5,600 fulfills the safe harbor, exempting you from penalties.

This scenario underscores the necessity of adapting prepayments, particularly with increased income from sources like stock sales or bonuses. Consult with us at Thomas Hawbaker CPA PLLC to verify your safe harbor status and adjust accordingly.

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State Variations and Other Considerations

Be aware that state guidelines may differ from federal rules—contact us for specifics regarding your state's requirements.

Deadlines on Weekends & Holidays

If a due date falls on a weekend or legal holiday, it shifts to the next business day.

Extensions for Disaster Areas

For regions identified as disaster areas, filing deadlines are extended. For the latest updates, check FEMA and IRS resources.

Thomas Hawbaker CPA PLLC is committed to helping you navigate these complexities with precision and expertise. Contact us today to optimize your tax planning and compliance strategy.

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