2026 tax year · Illinois
Is an S-corp election worth it in Illinois?
On $100,000 of profit the election saves about $3,594 a year in Illinois, after everything Illinois charges the company.
Work it out on your own numbers
The figures below use $100,000 of profit and our standard assumptions. Put your own in instead, this compares staying a sole proprietor against electing, with Illinois's own charges on the company included:
Salary share and withdrawal share are percentages. The withdrawal figure only affects the C corporation, it is what decides whether the second layer of tax applies at all.
Enter your figures above and press Compare.
What the election is worth on $100,000 of profit
A single filer taking the standard deduction, paying themselves 40% of profit as salary, with $1,500 a year of payroll and filing cost:
| Tax as a sole proprietor | $26,965 |
| Tax as an S-corp, federal and personal state | $21,871 |
| Saving from the payroll-tax split alone | $5,094 |
| What Illinois charges the company | − $1,500 |
| Net saving | $3,594 |
Illinois charges the company 1.5% of net income.
The profit range where it actually pays in Illinois
Between about $25,000 and $460,000 of profit. It stops paying above that: the payroll saving flattens once salary passes the Social Security wage base, while Illinois's charge keeps climbing with profit.
| Net profit | Sole proprietor | S-corp, all in | Difference |
|---|---|---|---|
| $60,000 | $14,797 | $12,633 | saves $2,165 |
| $100,000 | $26,965 | $23,371 | saves $3,594 |
| $150,000 | $44,508 | $39,006 | saves $5,502 |
| $250,000 | $77,458 | $74,192 | saves $3,266 |
What Illinois does differently
Illinois taxes the profit either way. Whether you take it as self-employment income or as salary plus distribution, roughly $4,950 of Illinois income tax sits on $100,000 of profit, the election moves the payroll-tax half of the bill, not the state half.
Illinois is one of 31 states with a pass-through entity tax. Entity pays state tax on behalf of owners. Owners get state tax credit on their personal return. The entity-level payment is deductible as a business expense, bypassing the $40,400 SALT cap. That is a genuine reason to elect beyond the payroll-tax saving, and it is not in the figures on this page, the calculation below is federal payroll tax against Illinois income tax as an individual.
The Illinois detail
Illinois charges the S corporation itself a 1.5% Personal Property Replacement Tax on its net Illinois income, IDOR verbatim: 'Partnerships, trusts, and S corporations pay a 1.5 percent replacement tax on their net Illinois income.' The election is recognized automatically by reference to IRC 1361(a); the entity files IL-1120-ST and is subject to replacement tax but not Illinois income tax. Owners who assume S corp income is untaxed at entity level in Illinois are wrong, 1.5% comes off the top before anything passes through. The separate franchise tax still exists in statute but the first $10,000 of liability is exempt for tax years from 1/1/2025, zeroing it for essentially all small corporations. Independently confirmed by a second researcher against tax.illinois.gov and the IL-1120-ST instructions (R-07/26), which compute the tax as Line 3 x .015. On the franchise tax: claims that no payment is required from 1/1/2026 trace to PENDING bills (HB2846/HB2861/SB3441, 104th General Assembly), not to enacted law, the compiled statute 805 ILCS 5/15.35 still shows only the $10,000 exemption from 1/1/2025. Re-check before publishing in case a 2026 Public Act has not yet reached the compilation.
How much salary to pay yourself
Enter your figures above and press Calculate.
Less salary means less payroll tax, so the arithmetic always points at the smallest salary you can justify. That is exactly why it is not a number to optimize: compensation has to be reasonable for the work you do, and the penalty for getting it wrong is reclassification plus back payroll tax. The cheapest row here is the riskiest one.
| Salary share | Salary | Distribution | Total tax | vs sole proprietor |
|---|---|---|---|---|
| 20% | $20,000 | $76,970 | $18,343 | $8,621 |
| 30% | $30,000 | $66,205 | $20,107 | $6,858 |
| 40% | $40,000 | $55,440 | $21,871 | $5,094 |
| 50% | $50,000 | $44,675 | $23,635 | $3,330 |
| 60% | $60,000 | $33,910 | $25,399 | $1,566 |
What this assumes
- Single filer, standard deduction, the business as the only income.
- 40% of profit taken as salary in the headline figures.
- $1,500 a year for payroll and a separate 1120-S, a cost estimate, not a tax figure, and it varies by provider.
- Comparing against a sole proprietorship. If you already trade through an LLC, some state fees are owed either way and are not a cost of electing.
- Anything listed as not modeled above is genuinely owed, it is excluded because it does not depend on profit, not because it is nil.
What these words mean
- Pass-through
- A business that pays no tax itself, its profit passes through to the owners, who pay tax on it on their personal returns. S corporations, partnerships and most LLCs work this way.
- Franchise tax
- A charge for the privilege of operating as a company in a state. Despite the name it has nothing to do with franchises, and it is often owed whether or not the business made money.
- Entity level
- A tax charged to the company itself, before any profit reaches the owners, as opposed to a tax the owners pay on their own returns.
- S corporation election
- Asking the tax office to treat your company as a pass-through, so profit is taxed to you rather than to the company. The owner takes a salary and the rest as a distribution, which is what saves payroll tax.
- Distribution
- Profit paid out to a company’s owner that is not salary. It is not subject to payroll or self-employment tax, which is the whole point of the S corporation election. And why the salary has to be defensible.