S Corp Self Employment Tax Calculator in Excel

Quick Answer: An S corp self-employment tax calculator compares two numbers: self-employment tax on 92.35% of your whole profit as a sole proprietor, and payroll tax on only the salary an S corp pays you. The difference, minus the extra costs of running payroll and filing a corporate return, is the savings. The IRS requires a reasonable salary, so the salary input can't be set artificially low.

You can build an S corp versus sole proprietor tax comparison in about fifteen spreadsheet cells. Enter your expected net profit, a reasonable salary, and your added S corp costs; the sheet computes self-employment tax both ways and the net savings. At $120,000 of profit and a $60,000 salary, the gap before costs is about $7,775.

The calculator, cell by cell

Open a blank sheet in Excel or Google Sheets and put labels in column A, values in column B. Inputs are in rows 2 to 6; everything below is a formula.

The 2,700 in B5 is a placeholder. Replace it with real quotes: a payroll service, the extra fee your preparer charges for Form 1120-S, and any state franchise or entity fees. Those vary widely by state and provider, so this article doesn't suggest figures.

Where do the rates in the formulas come from?

Every constant above comes from IRS pages read on 2026-10-27:

• 15.3% self-employment tax, made of 12.4% Social Security and 2.9% Medicare, applied to 92.35% of net earnings from self-employment (IRS Topic 554). Topic 554 also says self-employment tax applies once net earnings reach $400.
• Payroll tax on wages: 6.2% Social Security plus 1.45% Medicare from the employer, and the same from the employee, 15.3% combined. The Social Security wage base for 2026 earnings is $184,500; Medicare has no cap (IRS Topic 751).
• Additional Medicare tax of 0.9% applies above $200,000 of wages for withholding, and Topic 554 lists self-employment thresholds of $250,000 for married filing jointly, $125,000 married filing separately, and $200,000 for others. The basic calculator ignores it; add a row if your income is near those levels.

The wage base changes every year. Keep it in its own cell (B4) so you update one number in January rather than hunting through formulas.

Why the salary row is the one the IRS cares about

The whole saving comes from profit that leaves the S corp as a distribution instead of wages, because distributions are not subject to payroll tax. That makes it tempting to type 20000 into B3 and watch the savings climb. The IRS closes that door. On its page about S corporation compensation, it says an S corp must pay reasonable compensation to a shareholder-employee for services before making non-wage distributions, and that it can reclassify distributions as wages. The page cites court cases where it did exactly that.

The IRS lists factors used to judge what is reasonable, including:

1. Training and experience
2. Duties and responsibilities
3. Time and effort devoted to the business
4. Dividend history
5. Payments to non-shareholder employees
6. Timing and manner of paying bonuses to key people
7. What comparable businesses pay for similar services
8. Compensation agreements
9. Use of a formula to determine compensation

In practice, figure out what you would have to pay someone else to do your job, document how you got the number, and put that in B3. The IRS guidance is at S corporation compensation and medical insurance issues.

What profit level makes an S corp worth it?

Below the Social Security wage base, the sole proprietor pays 15.3% × 92.35% ≈ 14.13% of profit, and the S corp pays 15.3% of the salary plus the fixed costs. Setting those equal gives a break-even profit:

=(0.153*B3 + B5) / (0.153*0.9235)

With a $40,000 salary and $2,700 of added costs, that comes to about $62,422. Below that profit, the S corp costs more than it saves; above it, the gap widens with each dollar of profit that flows out as a distribution.

The break-even is only as honest as the salary you assume. A reasonable salary usually rises with the work you put in, which is also what drives profit, so test a few pairs rather than one. A small sensitivity table helps:

In the last row, SE earnings of $184,700 just pass the wage base, so beyond that point the sole proprietor pays only the 2.9% Medicare part on extra profit and the savings grow more slowly. To make this in a sheet, put profits down column D and salaries down column E, then copy the formulas from rows 8 to 18 across, swapping the B references for the row's own cells.

What this calculator leaves out

Payroll taxes are only part of the comparison. Things the sheet does not model, which your tax preparer will:

• Income tax interplay. A sole proprietor deducts half of self-employment tax; an S corp deducts the employer half of payroll tax as a business expense. Both reduce taxable income, by different amounts.
• The qualified business income deduction, which can change when part of your profit becomes wages.
• Unemployment taxes on the salary, federal and state.
• Retirement contributions, which are tied to wages in an S corp and to net earnings for a sole proprietor.
• State treatment. Some states tax S corps at the entity level or charge minimum fees.
• Health insurance, which has specific S corp rules covered on the same IRS compensation page.

To become an S corp, the business files Form 2553 signed by all shareholders, and then files Form 1120-S each year, issuing Schedule K-1s to owners. The IRS's S corporations page lists the eligibility rules, including the 100-shareholder limit and the restriction on partnership, corporate and non-resident alien shareholders.

Getting a real profit number into B2

The calculator is only as good as the profit you feed it. If your books are up to date, use the profit and loss report. If they aren't, last year's business bank and card statements are the quickest route to an honest figure: total the income, subtract the business expenses, and set aside transfers and owner draws.

When those statements are PDFs, QuickBankConvert turns each one into spreadsheet rows with a signed amount column, so a SUMIF by category gives you income and expenses without retyping. The sole-proprietor half of this comparison is built out in more detail in our self-employed tax calculator spreadsheet, and if you go ahead with the election, QuickBooks for an S corp covers setting up owner payroll and distribution accounts.

Related guides

• Self-employed tax calculator spreadsheet: quarterly estimates for a sole proprietor
• Small business tax prep from bank statements: building the profit figure from statements
• Choosing a tax accountant for a small business: who should check the election before you file
• QuickBooks for an S corp: chart of accounts for salary and distributions