Quarterly Tax Estimator (Small Business)
Estimate your federal + state quarterly tax payments. Built for small business owners with pass-through income (LLC, S-Corp distributions, sole prop) and mixed W-2 + 1099 situations. 2025 tax year brackets.
Your Numbers
Business profit after expenses. Schedule C or K-1 income.
Include any W-2 from your S-Corp.
Total federal tax withheld from W-2 paychecks.
Used for safe harbor calculation. Leave blank if unknown.
How This Works
Safe harbor rule
You avoid the underpayment penalty if your combined withholding + quarterly payments equal at least:
- 90% of the current year's tax, OR
- 100% of last year's tax (110% if AGI > $150K)
We use the lower of these two so you don't overpay.
Why SE tax hits so hard
As a business owner, you pay both the employee (7.65%) and employer (7.65%) side of FICA — 15.3% total on your net earnings. That's on top of federal and state income tax. This is why S-Corp election is popular: it lets you pay a "reasonable salary" as W-2 (subject to FICA) and take the rest as distributions (no SE tax).
State tax approximation
This tool uses either the flat rate (for flat-tax states) or ~60% of the top marginal rate (approximating effective rate for progressive states). For precise state calculations, use your state DOR's estimated tax worksheet.
Estimate only, not tax advice.
This calculator uses 2025 federal brackets and simplified state calculations. It doesn't account for QBI deduction, credits (CTC, EITC), Additional Medicare Tax on high earners, NIIT, retirement contributions, HSA, or itemized deductions. For precise numbers, use IRS Form 1040-ES worksheets or work with a CPA.