LLC vs S-Corporation in Illinois: $200,000 Earnings Comparison (Schedule C vs S-Corp)
If you're a 1099 earner or single-member LLC in Illinois, you’ve probably heard that an S-Corporation can reduce taxes. That can be true—mainly by changing how payroll/self-employment tax applies—but it also adds payroll and compliance requirements. Below is a simplified, educational example showing the tradeoffs.
Key takeaway
In this illustration, the S-Corporation structure produces lower combined taxes than a Schedule C LLC at the same $200,000 earnings level. The difference is driven primarily by self-employment tax vs. payroll tax treatment and the split between W-2 wages and K-1 profit.
Assumptions used
- Business earnings: $200,000
- Filing status: Married Filing Jointly
- Standard deduction: Used (not itemized deductions)
- Business expenses: None included for modeling
- Illinois income tax: Included in this simplified model
- S-Corp salary assumption: $60,000 per year (i.e., $5,000/month), with remaining profit as K-1 pass-through
- QBI deduction: Included, subject to simplified limitation mechanics
Side-by-side scenario results (simplified)
| Line item | LLC (Schedule C on 1040) | S-Corp (60k W-2 wages) |
|---|---|---|
| Base earnings | $200,000 | $200,000 |
| Self-employment / payroll tax | $27,193 | $9,180 |
| W-2 wages paid to owner | — | $60,000 |
| Employer payroll tax (deducted in S-Corp profit) | — | $4,590 |
| K-1 pass-through profit | — | $135,410 |
| QBI deduction | $30,981 | $27,082 |
| Federal income tax (estimated) | $17,091 | $19,930 |
| Illinois income tax (estimated) | $8,937 | $9,383 |
| Total taxes (estimated) | $53,221 | $38,493 |
| After-tax amount (illustrative) | $146,779 | $161,507 |
This table is a simplified planning illustration and may not match a final return prepared with full facts and documentation.
Download the Excel model
Want to test different earnings and salary assumptions? Download the workbook used for this illustration. Gray cells are locked and white cells can be adjusted to model alternative scenarios.
What to consider before electing S-Corp status
1) Reasonable compensation is not optional
S-Corp savings depend on paying a defensible W-2 salary to the shareholder-employee. The model assumes $60,000. If the IRS believes wages are unreasonably low for the services performed, it may reclassify distributions as wages.
2) Payroll compliance is ongoing
If you take a salary under an S-Corp, a best practice is consistent payroll. For a $60,000 salary, that typically means $5,000 per month paid from the business bank account.
- Make federal payroll tax deposits using EFTPS.
- File Form 941 each quarter.
- Issue a Form W-2 annually.
3) S-Corps add a separate tax return and more admin
S-Corps typically require an annual corporate return, a K-1 to the owner, payroll filings, and clean bookkeeping. The tax savings should exceed the added compliance burden.
4) Expenses, deductions, and income mix can change results
Real planning should incorporate allowable business expenses, retirement strategy, itemized deductions, and other income. This example is intentionally simplified.
S-Corporation election timing (Form 2553)
If you want an S-Corporation election effective for tax year 2026, the standard deadline to file Form 2553 is generally March 15, 2026.
