Corporate AMT Liability Estimator

See whether the 15% corporate alternative minimum tax will trigger a top-up payment. Enter adjusted financial statement income, the CAMT adjustments that increase the base, and your regular corporate tax bill. The calculator applies the 15% CAMT rate, subtracts allowed credits, and shows any incremental tax owed beyond the regular system along with effective rates for both regimes.

AFSI after Section 56A adjustments for the current tax year.
Add-backs that increase the CAMT base (e.g., accelerated depreciation, tax depreciation in excess of book).
Tax computed under the regular corporate system before CAMT.
Defaults to $0. Include only credits allowed against CAMT per Section 53.

For estimation only. Confirm Section 56A adjustments, credit eligibility, and consolidated group rules with your tax advisors before filing.

Examples

  • AFSI $48,500,000, adjustments $3,200,000, regular tax $7,350,000, credits $950,000 ⇒ CAMT base: $51,700,000.00 • Tentative CAMT at 15.00%: $7,755,000.00 • Credits applied: $950,000.00 • Net CAMT: $6,805,000.00 (effective rate 13.16%) • Regular tax rate on CAMT base: 14.21% • Additional CAMT owed above regular tax: $0.00.
  • AFSI $62,000,000, adjustments $5,500,000, regular tax $8,150,000, credits left blank ⇒ CAMT base: $67,500,000.00 • Tentative CAMT at 15.00%: $10,125,000.00 • Credits applied: $0.00 • Net CAMT: $10,125,000.00 (effective rate 15.00%) • Regular tax rate on CAMT base: 12.07% • Additional CAMT owed above regular tax: $1,975,000.00.

FAQ

Do I include prior-year CAMT credit carryforwards?

No. The optional credits field captures current-year CAMT foreign tax credits and general business credits permitted under Section 53. Prior-year CAMT credits offset regular tax in future years and should be handled in separate schedules.

What if my adjustments decrease AFSI?

Enter the net positive adjustments. If Section 56A adjustments reduce the base, input zero and track the reduction separately, as CAMT cannot drop below zero for the base computation.

Can this handle multiple controlled group members?

Aggregate AFSI, adjustments, and regular tax across the controlled group before entering totals so the test reflects the combined CAMT exposure.

Additional Information

  • CAMT applies a 15% rate to adjusted financial statement income for corporations averaging at least $1 billion in AFSI over three years.
  • Include add-backs for accelerated depreciation, tax-exempt income adjustments, and other Section 56A modifications in the adjustments field.
  • Only CAMT-eligible foreign and general business credits reduce tentative CAMT; others remain trapped until you generate regular tax in future years.
  • A positive top-up indicates CAMT exceeds regular tax and must be paid for the current year.

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