For educational purposes only — not tax, legal, or financial advice. Tax laws change frequently. Consult a qualified CPA, Enrolled Agent, or tax attorney for your specific situation.

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    Quarterly Estimated Tax Calculator (2026)

    Determine your safe-harbour quarterly estimated tax payments for Form 1040-ES. Compare the prior-year (100% / 110%) and current-year (90%) safe harbours, see federal quarterly due dates, and get state-specific guidance.

    Guidance, not advice. This calculator runs the rules as published, it doesn't assess your circumstances. Your actual tax may be affected by factors it doesn't cover (deductions, credits, filing status nuances, state-specific adjustments). Always seek financial or tax advice from a qualified CPA, Enrolled Agent, or tax attorney, or contact the IRS. Read our editorial scope →

    Your 2026 estimate

    Enter your estimated current-year income, prior-year tax liability, and any amounts already withheld or paid.

    Estimated income

    Deductions & credits

    Typically equals your SE income.

    Prior year & payments

    Line 24 on your 2025 Form 1040 (federal + state + SE).

    Determines 110% vs 100% safe harbour threshold ($150,000).

    W-2 withholding + any 1040-ES payments already made.

    Current-year tax estimate

    Based on your inputs using 2026 federal + state brackets.

    Federal income tax
    $7,729
    State income tax
    $9,888
    Self-employment tax
    $11,304
    Total estimated tax
    $28,921

    Safe harbour analysis

    Pay the lower of the two safe harbours to avoid §6654 underpayment penalty.

    100% prior-year Recommended
    $25,000

    100% of prior-year tax liability

    90% current-year
    $26,028

    90% of estimated current-year tax

    Recommendation
    Pay at least $25,000 for the 2026 tax year (100% prior-year safe harbour). This is the lower of the two thresholds, so it gives you the maximum protection against underpayment penalties while minimizing early payments.
    Underpayment risk
    You have paid only $0 so far, but the recommended safe harbour is $25,000. If you do not make up the difference by the next quarterly due date, you may face §6654 underpayment penalties.

    Quarterly payment schedule

    Federal Form 1040-ES due dates and amounts.

    Q1
    $6,250
    Due April 15, 2026
    Q2
    $6,250
    Due June 15, 2026
    Q3
    $6,250
    Due September 15, 2026
    Q4
    $6,250
    Due January 15, 2027
    Annual total to pay$25,000

    ($25,000 recommended safe harbour)

    State estimated tax

    Your state mirrors the federal quarterly schedule.

    California mirrors federal dates. Underpayment penalty rate is the federal short-term rate + 3%. CA also requires estimated payments for LLCs with $800 minimum franchise tax.

    Uneven income? Consider the annualized method

    If your income is uneven (e.g., seasonal business), you may use the annualized income installment method (Form 2210, Schedule AI) to reduce or eliminate penalties for earlier quarters. This method recalculates each quarter's required payment based on year-to-date income, so you pay less in low-income quarters and more in high-income quarters.

    Example: if you earn $0 in Q1-Q2 and $200,000 in Q3-Q4, the even quarterly method above would require $40,000 in Q1 and Q2. The annualized method would require $0 in Q1-Q2 and the full amount in Q3-Q4, eliminating penalties for the earlier quarters.

    Form 2210 Underpayment Penalty Calculator