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We keep you up to date on the latest tax changes and news in the industry.

Key Tax Deadlines for Individuals in September 2025

September 2025 marks a critical point in the fiscal year for taxpayers, bringing essential responsibilities such as tip reporting and the third installment of estimated tax payments. Understanding the intricacies of the IRS safe harbor provisions and strategic planning for the upcoming year can safeguard you from hefty penalties and prepare you for the 2026 tax season.

2025 Fall Tax Planning and Beyond

It's crucial to start strategizing your tax obligations for the 2025 fall and effectively preparing for 2026. Contact our office to schedule a consultation and ensure all your tax planning needs are met.

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September 10: Employee Tip Reporting

If you’re an employee in a tipping role and received over $20 in tips during August, you must report this income to your employer by September 10 using IRS Form 4070. Your employer is obligated to withhold FICA and income taxes on these tips. Insufficient regular wages to cover the withholdings will result in the uncollected amount being noted on your W-2 form in box 8. You’ll need to reconcile this when filing your tax return.

September 15: Estimated Tax Payment Due

The “pay-as-you-earn” tax system mandates the third quarterly payment of 2025 estimated taxes by this date. This system supports tax compliance through:

  • Payroll withholding for employees;

  • Pension withholding for retirees;

  • Estimated tax payments for those with non-withheld income.

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Failure to meet the minimum prepayment amount, commonly known as the safe harbor, can result in penalties. These are calculated based on the federal short-term rate plus three percentage points on a quarterly basis.

To avoid the penalty, federal tax law provides two safe harbor options:

  • Pay at least 90% of the current year’s tax liability.

  • Pay 100% of the previous year's liability, increasing to 110% if your AGI surpasses $150,000 ($75,000 if filing separately).

Example: If your current tax liability is $10,000 and prepayments are $5,600, the deficit is $4,400. Checking against the first safe harbor condition, $9,000 (90% of $10,000) exceeds your prepayments, triggering a penalty. However, if last year's tax was $5,000, your current prepayments of $5,600 exceed the 110% threshold, qualifying for penalty exemption under the prior year condition.

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This highlights the imperative of accurate prepayments, especially amid significant income spikes from asset sales, bonuses, or retirement transitions. The timeliness of estimated tax payments is key to securing the safe harbor protection. For detailed advice on your safe harbor estimates, reach out to our office promptly.

CAUTION: State-specific de minimis amounts and safe harbor rules may diverge from federal guidelines. For tailored state advice, please contact our office.

Weekends & Holidays: Should a deadline coincide with a weekend or public holiday, it automatically extends to the next business day.

Disaster Area Extensions:
In regions designated as disaster areas, deadlines receive automatic extensions. Verify disaster statuses and relevant dates via the following resources:

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