PFCHow to use this calculator
Build an equal-installment plan from a complete tax estimate and your prior-year figures. The result is a payment-planning tool, not a penalty calculation.
- Review the example inputs and replace them with the figures for your scenario.
- Check the assumptions and select Calculate to view the estimate.
- Compare a second scenario or open the breakdown and download the full CSV.
Illustrative example
With the example inputs, annual estimated-payment target is $10,000.00. Equal-installment planning only. Prior-year factor: 100%. Paying late can still incur a penalty; the remaining amount does not repair missed installments. Excludes annualized-income and farmer/fisher exceptions.
These example values are for explanation. They are not current market quotes or personalized recommendations.
Calculation method
Compare 90% of current-year tax after refundable credits with 100% or 110% of qualifying prior-year tax, then subtract withholding. The higher prior-year factor applies above the AGI threshold. The general under-$1,000 balance exception is checked.
Assumptions and limitations
Uses general federal rules for individuals with even income/payment timing and standard due dates. Prior-year tax must be the applicable safe-harbor amount from a full 12-month return. No annualized-income method, special farmers/fishers rules, disaster extensions, penalty computation, or timing allocation of payments already made. Payment targets do not erase late-installment penalties.
Sources
2026 estimated tax payment calculator FAQs
Choose a question to read the answer, then try your own numbers in the free calculator.
Does paying the remaining amount remove a penalty?
Not necessarily. Installment timing matters. This tool does not determine whether previous payments were timely or sufficient.
Why might I still owe at filing after meeting a safe harbor?
A safe-harbor target can be less than your final tax liability. The balance can still be due with the return.
Does the tool calculate business and self-employment taxes?
No. Enter a complete projected tax amount that already includes applicable taxes.
Is this calculator free?
Yes. You can calculate and download the breakdown without creating an account.
Are my numbers saved?
The app sends inputs to its calculation API to produce the result, but does not save them in an app database or browser storage.
PFC provides mathematical planning estimates. Tax and retirement rules in these tools are for 2026 and do not update automatically. Check the cited sources and the terms that apply to your situation.