Self-Employment Tax Calculator — Quarterly Estimates (2026)

Yes, by default, and you can switch it off. The qualified business income (QBI) deduction (Section 199A) lets many sole proprietors and freelancers deduct up to 20% of their business income from their federal taxable income. Qualified business income is your profit less the deductible half of your self-employment tax (26 CFR § 1.199A-3), and the deduction cannot exceed 20% of your taxable income. It lowers income tax only, not self-employment tax.

Example: $80,000 of profit, Single, standard deduction. Half of the self-employment tax is $5,652, so taxable income before the deduction is $58,248 and the deduction is 20% of that, $11,650. Federal income tax falls from $7,527 to $5,344, a saving of $2,183. With no other income the taxable-income limit is the one that applies, which is the same arithmetic as the IRS regulation's own first example (§ 1.199A-1(c)(3)).

For 2026 the income thresholds are $201,750 of taxable income for Single and Head of Household and $403,500 for a joint return (IRS Revenue Procedure 2025-32, section 3.26). Above them the deduction phases in a limit based on the wages the business pays and the cost of its depreciable property, over the next $75,000 ($150,000 joint), a range widened for 2026 by the 2025 budget act. A business with no employees and no depreciable property has a limit of zero, so its deduction shrinks to nothing across that range, and this calculator models exactly that case. The law also gives a minimum deduction of $400 to a business owner who materially participates and has at least $1,000 of QBI, starting in 2026.

A “specified service” business (health, law, accounting, actuarial science, performing arts, consulting, athletics, financial services, brokerage, investing or trading, or one whose principal asset is the reputation or skill of its owners) is reduced faster inside the range and gets no deduction above it (26 CFR § 1.199A-5). Whether your work counts is a question of fact; the calculator lets you tell it, and only asks once your income reaches the threshold.

In two ways. First, your wages and your self-employment earnings share one Social Security wage base ($184,500 for 2026): Schedule SE subtracts your W-2 Social Security wages from it, and the 12.4% applies only to what is left. A freelancer with $160,000 of wages pays the 12.4% on only $24,500 of earnings, and one with wages above the base pays none, though the 2.9% Medicare tax has no cap and is due on every dollar. Second, the 0.9% Additional Medicare Tax looks at wages and self-employment earnings together: wages over $200,000 (single) or $250,000 (joint) are taxed, and your wages also reduce the threshold for your earnings (Form 8959: a single filer with $145,000 of earnings and $130,000 of wages owes it on $75,000).

Your paycheck withholding covers only your wages. Everything the side business adds comes on top of your wages, so its income tax is figured at your highest bracket, not the lowest ones. Tick the box above the results to enter your wages, a spouse's wages and other income; the calculator then shows how much of the year's tax the business adds, subtracts what is already withheld, and splits the rest into quarterly payments. A spouse's wages count toward the joint Additional Medicare Tax threshold and the income tax, but not toward your Social Security wage base.

It reduces income tax, not self-employment tax: the credit is limited by your income tax on Form 1040 (Schedule 8812 starts from the tax on line 18), while the 15.3% Schedule SE tax is reported separately on Schedule 2 and no credit here reduces it. For 2026 it is $2,200 for each child under 17 with a Social Security number and $500 for each other dependent, reduced by $50 for every $1,000 (or part) of adjusted gross income over $200,000 ($400,000 joint). Tick the dependents box above to include it.

Example, head of household with one child and $80,000 of profit, Texas: self-employment tax is $11,304 either way, federal income tax falls from $4,465 to $2,265, and the total to pay for the year falls from $15,769 to $13,569. If the credit is more than the income tax, part of the rest is refundable, up to $1,700 per child and 15% of your earnings over $2,500. Form 1040-ES (line 11b) lets you subtract that refundable part from your estimated tax, so it lowers the quarterly payments too. Because the credit uses up tax that the QBI deduction would otherwise save, the deduction can show a smaller benefit once you add children. The earned income credit, the child and dependent care credit, the education credits and the saver's credit have their own options.

Yes. Both credits (26 U.S.C. § 25A, Form 8863) depend on your modified adjusted gross income, which here is your income after the deduction for half of the self-employment tax, not on whether you are an employee. The American opportunity credit is up to $2,500 per student for the first four years of college and 40% of it is refundable; the lifetime learning credit is 20% of up to $10,000 of other expenses. Both shrink between $80,000 and $90,000 of income ($160,000 to $180,000 joint). They reduce income tax, not self-employment tax.

Example, single with $60,000 of profit in Texas and one student with $4,000 of adjusted expenses: the credit is $2,500, of which $1,000 is refundable, and the total estimated tax falls from $12,037 to $9,537. The credits are claimed after the child and dependent care credit and before the saver's credit and the child tax credit. Tick the box above to include them; who may claim a student and the Form 1098-T rules are not checked.

For a sole proprietor the usual “25% of pay” limit is really about 20% of your profit less half of your self-employment tax, because your own contribution lowers the earnings it is based on: IRS Publication 560 handles this with a reduced rate of 0.2 (the plan rate divided by one plus the plan rate) in its Deduction Worksheet for Self-Employed. The most any one person can receive is $72,000 for 2026, plus catch-up contributions for a solo 401(k) at 50 or older. A solo 401(k) also lets you defer up to $24,500 of your own earnings, which is added to the employer part, so at low profits it allows far more than a SEP (the deferral can use almost all of your net earnings).

Example, single with $100,000 of profit in Texas: a SEP allows $18,587 and a solo 401(k) $43,087 (the same employer part plus the $24,500 deferral). The deduction lowers income tax, not self-employment tax, and also lowers your qualified business income (26 CFR § 1.199A-3(b)(1)(vi)), so the 20% QBI deduction shrinks a little. In this estimate the SEP saves $2,891 in income tax and the solo 401(k) $5,243. It is a deferral: you pay tax when you withdraw. Tick the box above to use your own profit, and set a smaller amount if you do not want the maximum.

Yes, if you have a net profit and the plan is established under your business (a policy in your own name counts). The self-employed health insurance deduction (Form 7206, Schedule 1 line 17) covers medical, dental, vision and Medicare premiums for you, your spouse, your dependents and a child under 27, and long-term care premiums up to an age cap per person ($500 at 40 or younger, up to $6,200 over 70 for 2026). It is limited three ways: by what the business earned (profit less half the self-employment tax and less any SEP or solo 401(k) deduction, so a maximum plan contribution leaves less room), by any month you or your spouse could have joined a subsidized employer plan, and by the Marketplace credit rules in Publication 974 (not modelled: the deduction and the credit depend on each other, so a Marketplace plan with advance payments of the credit needs that publication's worksheets). It does not lower self-employment tax (26 U.S.C. § 162(l)(4)).

Example, single with $80,000 of profit in Texas and $12,000 of premiums: the whole $12,000 is deducted, but it also lowers qualified business income (26 CFR § 1.199A-3(b)(1)(vi)), so the 20% QBI deduction falls by $2,400 and taxable income falls by $9,600, not $12,000. Both ends sit in the 12% bracket, so the saving is $1,152 (self-employment tax is unchanged at $11,304). At $10,000 of profit the same premiums would be limited to $9,294; the rest can be a medical expense on Schedule A if you itemize and your medical expenses pass 7.5% of adjusted gross income (not modelled here). Tick the box above to use your own premiums.

Yes. The saver's credit (Form 8880, 26 U.S.C. § 25B) counts up to $2,000 per person of contributions to an IRA, SEP, SIMPLE, 401(k) or similar plan, and pays 50%, 20% or 10% of it depending on adjusted gross income: for 2026 the 50% rate applies at or below $24,250 (single), $36,375 (head of household) or $48,500 (joint), the 10% rate up to $40,250 / $60,375 / $80,500, and nothing above (IRS Notice 2025-67). Adjusted gross income here is your income after the deduction for half of the self-employment tax. The credit reduces income tax only (not self-employment tax), is not refundable, and you must be 18 or older, not a full-time student and not claimed as a dependent. Withdrawals from retirement accounts in the last two years and up to the filing deadline reduce what counts.

Example, single with $30,000 of profit in Texas who puts $2,000 into a SEP or IRA: the credit is $200 (10% of the $2,000) and the year's total estimated tax falls from $5,181 to $4,981. This calculator does not also deduct the contribution from your income (a SEP or deductible IRA would lower taxable income further), so it understates the full saving. 2026 is the last year for this form of the credit; from 2027 it is replaced by a government match paid into the retirement account (Form 8880 instructions). Tick the box above to include it.

Yes, if you pay for care of a child under 13 (or a dependent or spouse who cannot care for themselves) so that you can work, and file Form 2441. Starting with tax year 2026 the credit is 50% of up to $3,000 of expenses ($6,000 for two or more people) at an adjusted gross income of $15,000 or less, falling to 35% by $45,000 and to 20% by $105,000 ($210,000 on a joint return), after the 2025 budget law (P.L. 119-21 section 70405, 26 U.S.C. § 21). Your earned income, here your wages plus profit less half of the self-employment tax, limits the expenses that count, and on a joint return so does your spouse's (their wages, as entered above). It reduces income tax, not self-employment tax, and it is not refundable.

Example, single parent with one child, $60,000 of profit, Texas, $4,000 paid for care: only $3,000 counts, at 35%, so the credit is $1,050 and the total estimated tax falls from $12,037 to $10,987. The care credit is claimed before the child tax credit, so it uses up tax that credit could have offset. If you also have a dependent care FSA through a W-2 job, enter it: it reduces the expenses that count. Tick the box above to include it.

Yes. Self-employment profit is earned income, but the amount the credit uses is your net earnings from self-employment less the deductible half of the self-employment tax (plus any wages), not the profit itself (Form 1040 instructions, EIC Worksheet B). A net loss counts as zero. The credit is refundable and Form 1040-ES (line 11b) lets you subtract it from your estimated tax, so it can lower the quarterly payments. For 2026 the maximum is $4,427 with one qualifying child, $7,316 with two, $8,231 with three or more and $664 with none (IRS Rev. Proc. 2025-32 section 3.06); tick the earned income credit box above to include it.

Example, head of household with one qualifying child, $20,000 of profit, Texas: self-employment tax is $2,826, so earned income for the credit is $18,587, which is above the $13,020 where the credit tops out and below the $23,890 where it starts to shrink, so the credit is the full $4,427 and the year's total estimated tax falls from $2,826 to -$1,601 (negative means a refund when you file). Other income raises adjusted gross income, and once that is over the threshold the IRS worksheet takes the smaller of the credit for your earnings and the credit for your adjusted gross income. Investment income over $12,200 removes the credit altogether.

The rules (Publication 596) are the same as for an employee: a Social Security number valid for work for you, your spouse and each child counted, a home in the U.S. for more than half the year, a qualifying child under 19 (under 24 if a full-time student, any age if permanently and totally disabled) and younger than you who lived with you more than half the year, or, with no child, being 25 to 64 and not claimable as someone's dependent. The estimate follows the IRS EIC Table's method with the 2026 amounts; the 2026 table is not out yet, so your return can differ by a few dollars. Statutory employees, clergy and church-employee income, married filing separately, and the tie-breaker when two relatives could claim the same child are not modelled.

No. Schedule SE line 12 is the 12.4% and 2.9% tax only, and line 13, the deduction, is half of line 12. The 0.9% Additional Medicare Tax is figured on Form 8959, added on Schedule 2 and not deductible, so the calculator leaves it out of the deduction (and out of qualified business income).

Two Schedules SE (both spouses self-employed), unreported tips, married filing separately, farm income and the optional methods, interest and gains beyond the amount you type in as other income, a Marketplace plan with advance premium tax credit (Publication 974), months you could have joined a subsidized employer plan, S corporation shareholders and more than one plan or business (the self-employed health insurance deduction and a SEP-IRA or solo 401(k) for yourself have their own options), employees or depreciable property (which can raise the deduction above the range), itemized deductions, credits other than the child tax credit, the earned income credit, the child and dependent care credit, the education credits and the saver's credit, and any QBI deduction at the state level (the state estimate does not apply it). It also splits the annual estimate into four equal payments, where the IRS due dates fall in uneven periods. Use it to see the shape of your bill, and check it against the IRS worksheets or a tax professional before you pay.