Business Interest Limitation
Screen the small-business exception, estimate the §163(j) limit, and track current and carried business interest in Form 8990 order.
How is the §163(j) business-interest limit calculated?
For a non-exempt taxpayer, the preliminary limit is business-interest income plus 30% of supplied Form 8990 ATI plus floor-plan financing interest. A taxpayer at or below the annual gross-receipts threshold can use the small-business exception only if it is not a tax shelter.
- 2026 gross-receipts threshold: $32,000,000
- ATI percentage: 30%
- Current-year interest is used before carryforwards
Exception screen
Enter the combined amount if §448(c)(2) aggregation is required.
Form 8990 amounts
Exclude floor-plan financing interest entered below.
Supply Form 8990 ATI; this tool does not derive it from taxable income.
An in-place election requires allocation between excepted and non-excepted businesses, so this estimator suppresses dollar results.
Election and scope boundary
An electing real property or farming trade or business can be outside §163(j), but the election requires ADS for specified property and removes the special depreciation allowance for that property. This is a taxpayer-level estimate and does not model partnership or S-corporation special rules, basis limits, passive losses, capitalization rules, or interest allocation.
Questions
Does every business under the gross-receipts threshold escape §163(j)?
No. The small-business exception also excludes tax shelters, and controlled-group aggregation can change the gross-receipts result.
Does this calculator derive adjusted taxable income?
No. Enter ATI already computed under the Form 8990 rules. For tax years after 2024, those rules add back depreciation, amortization, and depletion deductions.
What happens to disallowed business interest?
Section 163(j)(2) treats disallowed business interest as paid or accrued in the succeeding tax year. This tool carries the unused amount forward without predicting when it can be deducted.
What does a real-property or farming election change?
The election can remove the specified trade or business from §163(j), but ADS applies to specified property and the special depreciation allowance is unavailable for that property. The election is generally irrevocable.
Related business-deduction tools
Sources & References
Primary references used for this content
IRC §163(j)(1) — limitation formula
Primary authority for the §163(j) formula, exception, ATI, carryforward, or election consequences
View on law.cornell.edu
IRC §163(j)(2) — carryforward
Primary authority for the §163(j) formula, exception, ATI, carryforward, or election consequences
View on law.cornell.edu
IRC §163(j)(3) — small-business exception
Primary authority for the §163(j) formula, exception, ATI, carryforward, or election consequences
View on law.cornell.edu
IRC §163(j)(7) — electing trades or businesses
Primary authority for the §163(j) formula, exception, ATI, carryforward, or election consequences
View on law.cornell.edu
IRC §168(g)(8) — electing real-property assets
Primary authority for the §163(j) formula, exception, ATI, carryforward, or election consequences
View on law.cornell.edu
IRC §168(k) — ADS property excluded from qualified property
Primary authority for the §163(j) formula, exception, ATI, carryforward, or election consequences
View on law.cornell.edu
IRC §448(c) — aggregation rule
Primary authority for the §163(j) formula, exception, ATI, carryforward, or election consequences
View on law.cornell.edu
Instructions for Form 8990 — ATI after 2024
Primary authority for the §163(j) formula, exception, ATI, carryforward, or election consequences
View on irs.gov
Instructions for Form 8990 — tax shelters
Primary authority for the §163(j) formula, exception, ATI, carryforward, or election consequences
View on irs.gov
Instructions for Form 8990 — election consequences
Primary authority for the §163(j) formula, exception, ATI, carryforward, or election consequences
View on irs.gov
Instructions for Form 8990 — deduction ordering
Primary authority for the §163(j) formula, exception, ATI, carryforward, or election consequences
View on irs.gov
Instructions for Form 8990 — 2025 gross-receipts test
Primary authority for the §163(j) formula, exception, ATI, carryforward, or election consequences
View on irs.gov
Rev. Proc. 2025-32 — 2026 gross-receipts test
Primary authority for the §163(j) formula, exception, ATI, carryforward, or election consequences
View on irs.gov
IRS questions and answers — ATI additions
Primary authority for the §163(j) formula, exception, ATI, carryforward, or election consequences
View on irs.gov
✓Rules checked September 7, 2026 against IRC §§163(j), 168 and 448, the current Form 8990 instructions, IRS FS-2026-14, and Rev. Proc. 2025-32.
Disclaimer: This calculator provides estimates for educational purposes only. Not tax, legal, or financial advice. Results may vary based on your specific circumstances. Consult a qualified CPA or tax professional for personalized guidance.