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Quarterly Estimated Tax Calculator
Turn an annual tax target into a simple schedule for the remaining federal estimated tax deadlines.
Use this as a planning guide. Due dates can shift for weekends and legal holidays, and penalties depend on timing. Confirm with the IRS and your CPA.
Next deadline
Apr 15, 2026
Q1 estimated payment for tax year 2026
Tip: if you’re paying the January due date, that’s typically Q4 for the prior tax year.
This can be a safe harbor amount or a planning estimate. If you don’t know it yet, use the safe harbor calculatorfirst.
Withholding counts as tax paid and generally reduces what you need to pay through quarterly estimates.
Enter the total of your federal estimated payments so far for tax year 2026 (excluding withholding).
Make your estimated taxes decision-ready
X1 builds a deadline checklist from your real return and helps you coordinate safe harbor, catch-up, and year-end planning.
No credit card required to start
Assumptions and limits
- Assumes you already know an annual target (safe harbor or tax estimate). It does not compute the target for you.
- Uses equal payments for planning (IRS payment periods are not equal calendar quarters).
- Does not calculate underpayment penalties or use the annualized income installment method (Form 2210).
- Federal-only. State estimated tax rules vary and aren’t included.
- Due dates can shift for weekends and legal holidays. This tool adjusts for weekends and major federal holidays, but always confirm timing with your CPA.
Sources
FAQ
What if I don’t know my annual target yet?
Start with the safe harbor calculator to estimate a penalty protection target, then use this tool to plan the remaining payment schedule.
Do IRS quarters line up with calendar quarters?
Not exactly. Federal estimated tax periods are uneven. This tool uses equal payments for planning and simplicity.
Can I pay everything at once?
You can, but the best timing depends on your situation and cash flow. If you’re behind, a catch-up payment can reduce penalties, but it may not eliminate them.
Does withholding count as a quarterly payment?
Withholding generally counts as tax paid and can reduce what you need to pay through estimated payments.
Do states use the same deadlines?
Not always. Some states have different forms, deadlines, and safe harbor rules. Confirm your state requirements separately.
Questions to ask your CPA
- Which safe harbor option is best for me this year?
- Should I use equal payments, or does the annualized income method (Form 2210) matter for my situation?
- Is it simpler to adjust withholding instead of making quarterly payments?
- If I missed a due date, what catch-up move reduces penalties most efficiently?
- How do state estimated tax rules differ from federal?
Decision support
Coordinate before the next deadline
The goal is to make your next deadline concrete and easy to coordinate.
- Do I know which safe harbor method applies this year?
- Have I added up withholding and payments already made?
- Do I know the next estimated tax deadline?
- Would adjusting withholding be simpler than quarterly payments?
- Do I need to coordinate state estimated taxes separately?
- Should I use prior-year or current-year safe harbor this year?
- If I’m short, what catch-up move reduces penalty most efficiently?
- Should I increase withholding to simplify the process?
