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Illinois Schedule SA – Specific Accounting Schedule for Fiscal-Year Filers (2026)

Last reviewed: 2025-11-07

Use the Illinois Tax Form Calculator Schedule SA: Specific Accounting Schedule (Fiscal-Year Filers) as a stand alone tax form calculator to quickly calculate specific amounts for your 2026 Illinois state tax return. Alternatively, you can use one of our Combined Federal and State Tax Estimators to quickly calculate your salary, tax, and take-home pay.

Schedule SA (Specific Accounting Schedule) is used by fiscal-year filers whose accounting period does not match the standard calendar year. Illinois requires prorated reporting of income, deductions, and credits that fall within the portion of the fiscal year overlapping the state’s tax year. This ensures only Illinois-source income earned during the appropriate period is taxed on Form IL-1040.

When to File Schedule SA

File this schedule if your fiscal year begins before and ends after December 31, or if you are required to report Illinois income for part of a nonstandard tax year. Common examples include estates, trusts, and individuals changing accounting periods.

How to Complete Schedule SA

  1. Enter your total income for the full fiscal year (Line 1).
  2. Enter income earned during the Illinois-reportable months (Line 2).
  3. Divide Line 2 by Line 1 to calculate the percentage of income taxable by Illinois (Line 3).
  4. Multiply your total adjusted gross income by this percentage (Line 4).
  5. Apply the Illinois rate of 4.95%. The result is your Illinois income tax for the fiscal portion (Line 5).

Attach this schedule to your Illinois return and keep detailed records of how the allocation was determined. Documentation may include accounting ledgers, contract dates, or payroll records.

Illinois Schedule SA – Specific Accounting Schedule (Fiscal-Year Filers) (2026)
1Total income for full fiscal year
2Income earned during Illinois-reportable months
3Percentage taxable by Illinois (Line 2 ÷ Line 1)
4Illinois taxable income (Line 1 × Line 3)
5Illinois tax (4.95%) × Line 4

Example

Example: A taxpayer operates on a fiscal year from July 1, 2024, through June 30, 2026. Total income for the fiscal year is $120,000. Of that, $60,000 was earned in 2025 (the Illinois tax year portion). Divide $60,000 by $120,000 = 0.5 (50%). Multiply $120,000 × 50% = $60,000 taxable to Illinois. Illinois tax = $60,000 × 4.95% = $2,970.

Specific Accounting Guidance

Why Schedule SA Is Important

Specific accounting prevents duplication or omission of income across overlapping tax years. It ensures Illinois receives tax only on income earned during its active taxable period and protects taxpayers from overpayment when reporting under different accounting cycles.

Last reviewed: 2025-11-07: If you believe this form requires an update, please contact us.

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Frequently Asked Questions

Mortgage vs take-home planning

Try the Mortgage Calculator and revisit this IL page.

Where do I mail the completed IL-1040-V and payment?

Mail the completed voucher and payment to the address printed on the voucher (Illinois Department of Revenue, Springfield IL 62726-0001) unless told otherwise during filing.

Do charitable gifts affect IL tax?

IL doesn’t mirror federal itemized deductions; charitable gifts matter federally, not typically for IL base.

Why don’t my payroll brackets match?

Employer systems use rounding/timing and supplemental methods; small variances are normal.

Does Illinois tax Social Security or pension income?

No. Illinois exempts most retirement income—including Social Security, pensions, and IRA withdrawals—from state income tax. These subtractions are reported on Schedule M.

Important Notes

All calculations are estimates for guidance only. Always review your return and consider professional advice when submitting official filings.