Tax season 2026 is different.
Accountants used AI to prepare thousands of returns. The AI generated deductions, calculated credits, and drafted supporting documentation.
The returns looked professional. Clients were happy with the refunds.
Now the IRS is sending audit notices.
The AI invented deductions that don’t exist. It misclassified income based on the outdated tax code. It fabricated documentation that looks real but isn’t.
And accountants can’t explain why they filed returns without verifying what the AI generated.
How Accountants Are Using AI
Tax professionals discovered that AI saves hours of work.
Deduction identification: AI reviews client documents and suggests deductions. It finds credits the accountant might have missed.
Form preparation: AI fills out tax forms automatically based on client data.
Research: AI answers complex tax questions faster than manual research.
Documentation: AI generates supporting schedules and explanations.
Most accountants started using AI in 2024-2025. By tax season 2026, AI tax prep is widespread.
The problem? AI doesn’t understand tax law. It generates content that sounds correct but violates tax rules.
What’s Going Wrong
AI invents deductions: Client mentions business expenses. AI generates a full schedule of deductions, including items the client never mentioned. Accountant includes them without verification.
AI misapplies tax code: AI uses outdated or incorrect interpretations of tax rules. Deductions are claimed that aren’t allowed.
AI fabricates documentation: AI creates supporting schedules with specific numbers and calculations. The numbers look legitimate, but aren’t based on actual client data.
AI makes aggressive positions: AI interprets ambiguous rules in the taxpayer’s favor without considering audit risk.
The accountant reviews the return quickly, sees that everything looks professional, and files it.
The IRS Is Noticing
The IRS has pattern recognition, too.
Returns with certain characteristics are getting flagged, including unusually high deductions in specific categories, documentation that follows identical formats across multiple unrelated returns, aggressive positions on issues the IRS is monitoring, and R&D tax credits with AI-generated supporting calculations.
When the IRS audits these returns, they discover the AI-generated content and disallow the deductions, assess penalties for negligence or substantial understatement, and question whether the accountant exercised professional judgment.
The Professional Liability Problem
When the IRS disallows AI-generated deductions, who’s liable?
The taxpayer pays the tax, interest, and penalties. Then they sue the accountant for malpractice because the accountant filed an incorrect return.
The accountant is liable for professional negligence if they relied on AI without verification.
The AI vendor isn’t liable. Their terms of service disclaim accuracy and say the AI is for “informational purposes only.”
Professional liability insurance may not cover AI-related malpractice if the insurance carrier argues the accountant was negligent in using AI without verification.
R&D Tax Credits Under Scrutiny
The IRS is specifically targeting AI-generated R&D tax credit claims.
Companies use AI to identify qualifying research expenses, calculate the credit amount, and generate the required documentation.
The AI generates impressive supporting calculations. It identifies expenses that qualify. It prepares detailed documentation.
The IRS audits these claims and finds the AI misidentified qualifying expenses, used incorrect calculation methods, and generated documentation that doesn’t match actual company activities.
R&D credits are being denied. Companies face substantial understatement penalties. Accountants face malpractice claims.
What Tax Professionals Should Do
If accountants are using AI for tax preparation, they need safeguards.
Verify every deduction: AI suggests a deduction, the accountant confirms it’s supported by actual client documentation, and properly applies tax law.
Research AI conclusions: AI interprets a tax rule, accountant verifies the interpretation using authoritative sources.
Review supporting calculations: AI generates schedules and numbers, and the accountant confirms the math and underlying assumptions are correct.
Disclose AI use to clients: Clients should know if AI is being used to prepare their returns and have the right to object.
Document the review process: Show what AI generated, what the accountant verified, and what changes were made.
Most accountants using AI do none of this because it eliminates the time savings that made AI appealing in the first place.
What Companies Should Do
If companies use in-house accountants or outside firms that use AI for tax prep, ask questions.
“Are you using AI to prepare our tax returns?”
“How do you verify AI-generated deductions and calculations?”
“What happens if the IRS disallows AI-generated positions?”
“Does your professional liability insurance cover AI-related errors?”
Most companies don’t know their tax preparer is using AI and have no idea what verification processes exist.
Schedule a 30-minute Tax AI Risk Assessment where we’ll:
- Identify if your tax preparers are using AI
- Show what verification requirements should exist
- Review your exposure to IRS audit risk
- Assess professional liability coverage gaps
- Create protocols for safe AI use in tax prep
Because AI-generated tax returns feel efficient until the IRS audit notice arrives.
Brian Alexander
Founding Partner, VisionAI+ Consulting Group
Former General Counsel, AI Engineering Firm
Certified ISO 42001 Lead Auditor