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    Quarterly Estimated Taxes: Avoid the Penalty

    2 min readIntermediateLast reviewed: April 2026
    Self-EmployedTax PlanningEstimated Taxes

    The transition from W-2 employment to self-employment brings a tax surprise that catches many new business owners off guard: the IRS doesn't wait until April to collect.

    Why Quarterly Payments Exist

    As a W-2 employee, your employer withholds taxes from every paycheck and the IRS receives your money throughout the year. When you're self-employed, there's no employer withholding. The IRS still expects payment throughout the year.

    The Due Dates

    The Safe Harbor Rules

    • 100% of prior year: Pay at least 100% of your total tax liability from last year in four equal installments. No penalty.
    • 110% rule: If AGI last year exceeded $150,000, pay 110% of prior year tax.
    • 90% of current year: Pay at least 90% of your actual current year tax liability.

    Underpayment penalties are essentially interest charges - roughly 7 to 8% annualized as of 2026. Not catastrophic, but avoidable.

    The Practical Approach

    Most self-employed individuals use the prior-year safe harbor because income is hard to predict. Pay 110% of last year's total tax in four installments. If you earn more, settle up at filing. No penalties, no stress about prediction accuracy.

    Setting Up the System

    The bottom line

    Set calendar reminders for April 15, June 15, September 15, and January 15 now.

    What would you do?

    Alex earned $150,000 in her first year of consulting. Her total tax liability was $38,000. She's estimating $180,000 in income for year two.

    Your Move

    Look at your prior year's total tax liability (Form 1040, Line 24). Divide by 4. That's your minimum quarterly payment to meet the 100% safe harbor (110% if AGI was above $150,000). Set calendar reminders for April 15, June 15, September 15, and January 15.

    Sources

    1. Internal Revenue Service, Publication 505

      Tax Withholding and Estimated Tax (estimated-tax and safe-harbor rules)

    Educational information only. Not financial, tax, or legal advice or a recommendation. Figures are drawn from the primary sources cited above; verify current amounts with the source before acting.

    Educational content only. Not financial, tax, or legal advice. Consult a qualified professional before making decisions based on your specific circumstances.

    Last reviewed: April 2026

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