Estimated Tax Calculator

Total Box 1 wages from all 2026 W-2s. Used for the income-tax and NJ GIT components.

Enter only the Social Security wages (Boxes 3 + 7) of the person who has the self-employment income. Do not include a spouse's wages. If left blank, the model uses Box 1 wages for single, head-of-household, and separate filers, and $0 on a joint return. This screen models one self-employed person.

Total Box 5 wages from all W-2s, for Additional Medicare Tax. Leave blank only if it equals Box 1.

Schedule C net profit plus general-partner self-employment earnings (Schedule K-1 (Form 1065), box 14, code A, including guaranteed payments). Do NOT include S-corporation K-1 box 1 income; it is not subject to SE tax (enter S-corp W-2 wages in the W-2 field instead). Enter S-corporation K-1 ordinary income under Other Income; the tool then treats it as investment income for the 3.8% NIIT, which overstates NIIT for an owner who works in the business.

Short-term gains are taxed at ordinary rates; include them in Other Income. Losses are not modeled.

Interest, non-qualified dividends, rental income, short-term gains, pensions, and similar. The whole entry is treated as net investment income for NIIT.

Your allowable 2026 Schedule A total after applicable limits (the SALT cap is $40,400 for 2026, or $20,200 if married filing separately, and phases down above $505,000 of modified AGI, or $252,500 if married filing separately). The model uses the higher of this amount or the $16,100 standard deduction for your filing status.

Only an allowable federal IRC 162(l) / Form 7206 deduction attributable to the self-employment income above. This tool does not test eligibility.

Only an allowable deductible contribution attributable to the modeled business. This tool does not calculate plan eligibility or contribution limits.

Enter the deduction you expect to claim; this tool does not compute it. It is applied as entered and cannot exceed taxable income before the deduction. Above the section 199A(e)(2) threshold ($201,750 single or head of household, $201,775 married filing separately, $403,500 married filing jointly, Rev. Proc. 2025-32) the SSTB, W-2 wage, and UBIA limits can reduce or eliminate it. The deduction is generally limited to 20% of taxable income less net capital gain, but for 2026 a taxpayer with at least $1,000 of qualified business income from an active business can claim a minimum of $400.

W-2 Box 2, plus any Additional Medicare Tax your employer withholds (the part of Box 6 above 1.45% of Box 5), plus other federal income tax you expect to be withheld during the year. Withholding is treated as paid in four equal parts on the installment dates (IRC 6654(g)).

Form 1040-ES amounts already paid for 2026. Applied to the earliest installments first.

Nonrefundable credits (reduce income tax only, not below zero), such as the nonrefundable child tax credit, education credits, and the saver's credit. They cannot offset self-employment tax, Additional Medicare Tax, or NIIT (Form 1040-ES (2026) worksheet lines 7-8).

Refundable credits (earned income credit, additional child tax credit, net premium tax credit, refundable American opportunity credit, refundable adoption credit, fuel tax credit, section 1341 credit), other than withholding and estimated payments. They come off after every tax is added (worksheet line 11b). The safe-harbor gates measure tax after both kinds of credit (IRC 6654(f)).

If a preparer or your own workpapers already give you a 2026 federal tax after credits (the Form 2210, line 4 figure), enter it and the safe-harbor gates will use it instead of this tool's modeled components. Leave blank to use the modeled figure.