The S-Corp question, in one paragraph
Once your freelance profit clears roughly $50k, the question stops being academic and starts paying for itself. As a sole proprietor you owe 15.3% self-employment tax on essentially every dollar of profit. As an S-Corp you owe FICA only on the "reasonable salary" you pay yourself; the rest is distributed as a K-1 distribution that the IRS does not touch with SE tax. The catch: running an S-Corp costs $1,500-4,000 a year in payroll, bookkeeping, tax prep and state fees. The election is worth it when the SE savings comfortably exceed that overhead.
How the math works in practice
Take a freelancer with $120,000 in net profit. As a sole proprietor she owes roughly $17,000 in SE tax (15.3% × 92.35% × $120,000, capped on the SS portion). As an S-Corp paying herself a $60,000 salary, she owes about $9,180 in FICA on the salary plus zero SE tax on the $60,000 distribution — total $9,180. Subtract $1,500 of S-Corp overhead and the net savings is roughly $6,300 a year. That is more than three months of rent in most US cities; year after year it compounds.
Where it usually does NOT work
- Profit under $40k. The overhead eats the savings.
- You hate paperwork enough to skip filings, miss deadlines, or pay penalties. The IRS will collect penalties efficiently and they wipe out years of SE savings.
- You live in a state with high franchise/annual report fees (California $800/year minimum, Tennessee $300+).
- Your "reasonable salary" would have to be 90%+ of profit (e.g. solo consultant whose only "asset" is their time) — the audit math then leaves nothing in the distribution to save tax on.
Common mistakes
- Setting salary too low. Paying yourself $20k in salary on $200k of profit gets you a juicy SE saving and a juicy IRS audit. The agency has won multiple cases reclassifying distributions as wages with back taxes plus penalties.
- Forgetting Form 2553 deadline. Election must be filed within 75 days of the start of the tax year (or formation). Miss it and you wait a year.
- Not actually running payroll. "I'll just take draws" doesn't work in an S-Corp. You need a real payroll system that issues W-2s, files 941 quarterly, and remits FICA on schedule.
- Skipping the corporate formalities. Separate bank account, basic minutes, no commingling. Otherwise you can lose the liability protection that motivated the LLC in the first place.
FAQ
How does an S-Corp save self-employment tax?
A sole proprietor pays 15.3% SE tax on net business profit (after the 92.35% factor). An S-Corp owner pays themselves a "reasonable salary" via W-2, which is subject to FICA, plus a "distribution" via K-1 that is NOT subject to SE tax or FICA. The savings come from the distribution portion.
What counts as a "reasonable salary"?
The IRS expects salary to reflect what you would pay someone else doing your job. There is no statutory percentage, but rough industry guidance for service businesses is 30-60% of profit. Set it too low and you risk an audit (the IRS can reclassify distributions as wages with back taxes and penalties). Common practice is to anchor against BLS wage data for your role and city.
What does "S-Corp overhead" include?
Realistically: payroll service ($30-60/month for Gusto, OnPay, etc.), bookkeeping (DIY or $100-300/month with a service), tax prep ($800-2000/year for an S-Corp 1120-S vs $300-600 for sole prop Schedule C), state franchise/annual report fees ($100-800 depending on state — California is famously $800/year minimum). Total typically $1500-4000/year.
At what profit level does S-Corp start to make sense?
Rule of thumb: somewhere between $40k and $80k of profit, depending on your state and how lean you can keep the overhead. Below $40k, the SE savings rarely cover the extra paperwork. Above $80k, the math usually works strongly in S-Corp's favor.
Are there downsides besides cost?
Yes. Stricter recordkeeping (corporate minutes, separate bank accounts, no commingling), payroll quarterly filings (941, state UI), annual 1120-S federal return + state corporate return, election deadline constraints (Form 2553 must be filed within 75 days of formation or start of tax year), and the "reasonable salary" audit risk. For most freelancers under $50k, the simplicity of sole prop wins.
Does this calculator include federal income tax?
No. Federal income tax is approximately the same in both structures because all profit (sole prop net or S-Corp salary + distribution) flows to your personal return. The savings difference lives entirely in the SE/FICA portion, which is what this tool isolates.
What about QBI deduction?
Both sole props and S-Corps can claim the 20% QBI deduction (Section 199A) if eligible. There are wrinkles: the S-Corp salary is W-2 wages (which factor into the QBI W-2-wages limit above the income threshold), while sole prop has no W-2 wages. Above the Section 199A income thresholds, the salary you pay yourself can change your QBI calculation. Out of scope for this estimator.
Should I trust this number to make the decision?
No — use it to start the conversation with a CPA or tax advisor. The S-Corp election is binding for the year and reverting (revocation or termination) is paperwork-heavy. Get a one-hour consult before you file Form 2553. The $200-400 you spend on the consult is cheap insurance.