Estimated Taxes
Last reviewed 2026-05-11 by Asad Ali, Founder & CEO
Quarterly tax payments made by self-employed individuals and businesses.
Estimated taxes are periodic payments made to the IRS (and often state agencies) by individuals and businesses that do not have enough tax withheld during the year — self-employed workers, freelancers, partners, S-corp shareholders, landlords, and anyone with substantial investment or side income. The federal system operates "pay as you go": tax must be paid throughout the year through W-2 withholding or quarterly estimates. Use Form 1040-ES (individuals) or Form 1120-W (C corporations) to compute and pay. Payments are due roughly April 15, June 15, September 15, and January 15 of the following year. Under the safe harbor rule, you avoid an underpayment penalty if you pay at least 90% of current-year tax or 100% of last year's tax (110% if last year's AGI exceeded $150,000), whichever is less. State estimated tax rules vary and often parallel federal due dates. Verify the current year's safe harbor thresholds and dollar limits with the IRS (Publication 505).
Formula
Safe Harbor = lesser of (90% of current-year tax) or (100% of prior-year tax; 110% if prior-year AGI > $150,000). Quarterly Payment = Annual Projected Tax ÷ 4Example
A consultant projects $90,000 in net self-employment income for the year. Estimated federal income tax (roughly 24% effective on taxable income after the SE tax deduction and standard deduction) ≈ $11,500. Self-employment tax = 15.3% × (92.35% × $90,000) ≈ $12,716. Total federal estimated tax ≈ $24,200. Divided by four, each quarterly payment is roughly $6,050 submitted via IRS Direct Pay or EFTPS by the four deadlines. State estimated payments are calculated separately under home-state rules.
Why It Matters for Your Business
Missing or underpaying estimated taxes triggers IRS penalties that accrue daily at the federal short-term rate plus 3%, so calculating and paying on schedule prevents surprise bills and fines at filing time.
Practical Tips
- •Use the IRS safe harbor (100% of last year's tax, 110% if high income) to lock in zero penalty even if you under-project the current year — see IRS Publication 505
- •Set aside 25–35% of each client payment in a separate savings account so estimated tax cash is never spent
- •Recalculate after any major income change — selling a property, receiving a bonus, or losing a contract can swing your estimated liability by thousands
- •Pay through IRS Direct Pay or EFTPS for free; never mail paper checks because lost or misapplied checks still draw underpayment penalties
Common Questions About Estimated Taxes
How is estimated taxes calculated?
The formula is: Safe Harbor = lesser of (90% of current-year tax) or (100% of prior-year tax; 110% if prior-year AGI > $150,000). Quarterly Payment = Annual Projected Tax ÷ 4. See the worked example below for a step-by-step calculation using realistic numbers.
What is an example of estimated taxes?
A consultant projects $90,000 in net self-employment income for the year. Estimated federal income tax (roughly 24% effective on taxable income after the SE tax deduction and standard deduction) ≈ $11,500. Self-employment tax = 15.3% × (92.35% × $90,000) ≈ $12,716. Total federal estimated tax ≈ $24,200. Divided by four, each quarterly payment is roughly $6,050 submitted via IRS Direct Pay or EFTPS by the four deadlines. State estimated payments are calculated separately under home-state rules.
Why does estimated taxes matter for my business?
Missing or underpaying estimated taxes triggers IRS penalties that accrue daily at the federal short-term rate plus 3%, so calculating and paying on schedule prevents surprise bills and fines at filing time.
How does FiscalInsights help with estimated taxes?
FiscalInsights tracks estimated taxes automatically as part of its AI bookkeeping workflow. Connect your bank accounts and the platform handles categorization, reconciliation, and reporting without manual entry.
Related Terms
More Taxes Terms
Tax Deduction
An expense that reduces taxable income.
Form 1099
IRS forms reporting various types of income other than wages.
Form W-2
Annual statement from employers showing employee wages and taxes withheld.
Payroll Tax
Taxes withheld from employee wages for Social Security and Medicare, plus employer-side employment taxes.
FICA
Federal Insurance Contributions Act taxes that fund Social Security and Medicare.
Related Taxes Guides
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