Audit Finding
OpenWrong form or line
Claude for Small Business
CA State Module -- Form 540 -- Wrong form or line
The Claim
Claude entered the total tax figure onto California Form 540 Line 40 (Nonrefundable Child and Dependent Care Expenses) instead of the correct Line 64 (Total Tax).The Error
Claude placed the computed total tax amount on Line 40 of California Form 540, which is designated for Nonrefundable Child and Dependent Care Expenses credit, rather than Line 64, which is the correct line for reporting total tax owed. This is a wrong-line mapping error in the generated Python script used to populate the PDF form. The correct placement of total tax on Line 64 is required by the California Franchise Tax Board's Form 540 instructions.
The Citation
California FTB Form 540 (California Resident Income Tax Return), Line 64 (Total Tax) and Line 40 (Nonrefundable Child and Dependent Care Expenses); California Revenue and Taxation Code §17041 (tax liability computation); FTB Form 540 Instructions (2024) Nauma.ai blog (March 30, 2026) — "Using Claude to File Taxes: Does It Save You Time or Money?"; github.com/robbalian/claude-tax-filing (claude-tax-filing skill)
Business Impact
A self-employed California resident relying on Claude-generated Form 540 without careful human review could submit a return with total tax misreported on the wrong line, potentially triggering an FTB audit, assessment of additional tax, penalties under California R&TC §19131, and interest on underpayment.
Verdict
KKATC Tax Response
Note
Source: Nauma.ai blog March 30 2026. Error confirmed in generated Python script visible in article. Claude placed total tax figure on Line 40 (Nonrefundable Child and Dependent Care Expenses) instead of Line 64 (Total Tax) on CA Form 540.KKATC Tax Prep and Consulting
This scenario is covered.
If AI gave you advice like this, a review costs less than the penalty. Twelve years of Fortune-level corporate tax experience.
Book a Consultation →