Q1 Estimated Tax: 15 April
First quarter federal estimated tax payment for self-employed people, freelancers, partners and others without sufficient withholding. Covers 1 January – 31 March income. The safe harbors are 90% of the current year tax, or 100% of last year's tax, rising to 110% when last year's adjusted gross income was above $150,000. The self-employment tax part is 15.3%, with the Social Security part applying only up to the 2026 wage base of $184,500.
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Who this applies to
- Self-employed people earning Schedule C income
- Partners receiving K-1 distributions
- S-corp shareholders with non-W-2 K-1 income
- Anyone with significant non-wage income (rentals, investment, capital gains)
What to file
Form 1040-ES voucher with payment, OR pay electronically via IRS Direct Pay / EFTPS without filing the voucher.
How to file
Online via IRS Direct Pay (free, ACH) or EFTPS. Paper Form 1040-ES voucher accepted with check.
Payment due
25% of expected annual tax (or per the safe-harbor rule of 100%/110% prior year).
Penalties for missing this deadline
Section 6654 underpayment penalty applies. Interest-based, calculated at the IRS underpayment rate, which is 7% for the fourth quarter of 2026, on the shortfall for each day it is late. Avoid by hitting safe harbor: 90% current year OR 100% prior year (110% if prior AGI > $150k).
Filing checklist
- Estimate net SE earnings and other taxable income for the current tax year
- Calculate federal income tax + 15.3% SE tax
- Subtract any anticipated W-2 withholding
- Pay 25% by 15 April via IRS Direct Pay
- Repeat for Q2 (15 June), Q3 (15 September), Q4 (15 January)
Documents you'll need
- Prior-year return to find last year's total tax
- Year-to-date profit and loss to project income
- Records of withholding from any W-2 job or spouse's job
- Previous estimated payment confirmations
Common mistakes to avoid
- Forgetting Q1 because it coincides with prior year tax filing
- Under-estimating because you ignore SE tax (it's 15.3% on top of income tax)
- Skipping a quarter and assuming you can catch up: penalty calculated quarterly
- Using IRS Direct Pay but selecting wrong tax year
Never miss a United States deadline
AccountsOS tracks every Internal Revenue Service (IRS) and State Secretary of State (varies by state) deadline and reminds you weeks ahead.
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