Federal quarterly estimated taxes are periodic payments toward annual income tax and self-employment tax liability. The IRS publishes due dates for Form 1040-ES payments, typically in April, June, September, and January following the tax year.
Self-employed taxpayers often pay quarterly because business income may not have withholding. Employees with side business income may also need estimated payments when withholding does not cover total federal liability.
A quarterly planning estimate usually starts with projected annual federal tax, then spreads remaining liability across due dates after accounting for withholding and prior payments. TaxChecker's Quarterly Tax Calculator models this using documented safe harbor rules when users supply prior-year tax information.
The Quarterly Tax Due Dates 2025 resource lists IRS due dates used in TaxChecker's tax-year configuration, including weekend and holiday adjustments where applicable.
Quarterly payments are not a separate tax—they are prepayments of federal income and self-employment tax that reconcile on the annual return. Underpayment penalties may apply when payments fall short of IRS rules; penalty calculations are excluded from TaxChecker calculators.
See Estimated Tax Safe Harbor Rules for the 90% and prior-year percentage tests. This content is educational federal reference material only.
Related content
Continue with calculators, guides, and related articles.
Calculators
- Quarterly TaxEstimate 2025 quarterly federal tax payments with IRS safe harbor rules and Form 1040-ES due dates. Free self-employed planner—not tax advice.
- Estimated TaxEstimate annual federal tax, remaining liability, and safe harbor targets for self-employed and mixed income. Free 2025 worksheet—not tax advice.
- Self-Employed TaxEstimate 2025 self-employment and federal income tax on net profit using Schedule SE rules and IRS brackets. Free calculator—not tax advice.
Resources
- Quarterly Tax GuideWho pays quarterly federal estimated tax, safe harbor rules, and how Form 1040-ES payments fit annual filing. Planning guide from IRS publications—not tax advice.9 min read
- Quarterly Due Dates 20252025 Form 1040-ES estimated tax due dates with weekend and holiday adjustments plus safe harbor overview. Federal deadline reference—not tax advice.4 min read
Articles
- Estimated Tax Safe Harbor RulesIRS safe harbor concepts for federal estimated tax: 90% of current year, 100% or 110% of prior year, and how planners use them in worksheets.1 min read
- Self Employment Tax ExplainedA federal-only overview of self-employment tax: what it funds, who it generally applies to, and how it differs from employee FICA withholding.2 min read
Estimates only — not tax advice, legal advice, or financial advice. TaxChecker is not affiliated with the IRS. Consult a qualified tax professional for your situation.