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How To Handle A FTB Audit

Written by Admin | December 29, 2025

How to Handle an FTB Audit

The Franchise Tax Board (FTB) is California's tax authority responsible for collecting state income tax for individuals and businesses. If you live or work in California, you could be audited. Learn what to expect if you get audited, how to protest audit findings and how to prepare for an audit.

What Is an FTB Audit?

A California Franchise Tax Board audit is a formal review of an individual's or a business's tax filing and supporting documents. An audit verifies that the information reported on a tax return is accurate and complete and determines whether the correct amount of tax was paid. Auditors look for potential tax problems, such as unpaid taxes or fraud, and objectively evaluate tax returns and other relevant documentation. They ensure audits and results comply with tax laws and support their recommendations with facts.

What to Expect During the FTB Audit Process

Generally, here's what you can expect during an FTB audit:

Audit Letter

You'll get a letter from the FTB informing you that you're being audited. The letter will include information about what tax year or years they're reviewing, issues with the return, additional information you need to provide, and how to contact the FTB. Timelines vary based on the complexity of the audit. However, the FTB aims to complete an audit within two years of initial contact or four years from when the tax return was filed.

You may have a representative with you anytime, such as an accountant or audit advisory specialist. To authorize someone else to represent you, you must submit California FTB Form 3520-PIT, the Individual or Fiduciary Power of Attorney Declaration.

Desk or Field Audit

You may get a desk or field audit. A desk audit is performed from the auditor's office via correspondence, while a field audit occurs where the records are. A field audit is generally done where a company does business, but it can also happen in an FTB office or a representative's office.

During the audit, you may need to schedule appointments, review documents you provided and respond to the FTB's findings. You may receive Information Document Requests asking for more documents or information.

Findings

Once the FTB has completed the audit, they'll notify you of their findings. Possible audit outcomes include:

  • No Change: Your return was accepted as filed.
  • Notice of Proposed Assessment (NPA): An NPA means you owe additional taxes, penalties or interest.
  • Notice of Proposed Adjusted Carryover Amount: This indicates a reduction of a carryover item but no additional tax.
  • Letter indicating a denied refund: The FTB has partially or fully denied your claim for a refund.
  • Letters indicating a refund: These have several names — Notice of Proposed Overassessment; Notice of Overassessment, Credit or Refund; or Computation of Proposed Overpayment — that all mean the state likely owes you money.

Protesting a Proposed Assessment

If you receive an NPA but disagree, you can file an official protest. Your notice will include a “Protest By” date, after which the proposed assessment is final and becomes billable. Note that filing a protest doesn't stop interest or penalties from accruing. You can file a protest online, by fax or by mail. The FTB will notify you once they receive your protest.

During the review, the FTB may request more information. You can also request a hearing where you can present supporting evidence or additional documents. Once the FTB has reviewed your protest, they'll send a Notice of Action (NOA) to let you know whether they've decided to withdraw, revise or affirm the audit results. Depending on the result, you may receive additional notices.

If you still disagree with the findings, you can appeal for up to 30 days after the date on the NOA. Include all the information and documents you received from the FTB when you appeal to the Office of Tax Appeals. Remember that interest and penalties continue to accrue.

Your Rights and Responsibilities

Taxpayers have certain rights under the California Taxpayers' Bill of Rights and the Taxpayers' Rights Conformity Legislation. Under these laws, you have the right to confidentiality, courteous treatment, clear and concise requests, and completion of the audit in a reasonable time. You also have the right to a representative and to protest and appeal audit findings.

In return, you have certain responsibilities toward the FTB. You should pay any taxes promptly and in full or make arrangements with the FTB for a payment plan. You should also keep communicating with your auditor. If they request a document, get it to them promptly. If you have difficulty fulfilling a request, let them know so you can work together to find the needed information. An audit isn't meant to punish you, but being uncooperative or nonresponsive can invite deeper inspections and additional penalties.

How to Prepare

If you receive a letter that you're being audited, start by organizing your financial records, such as tax returns, bank statements, receipts and invoices. You may want to review your tax returns yourself to ensure you've reported all income and deductions accurately. If you do discover mistakes, you can file an amended return, which could stop the audit.

It's often best to consult with a tax professional during an audit, especially if you find tax law and regulations confusing. A professional audit advisor can explain the process and walk you through all the steps. They'll help you understand your rights and can represent you during the audit.

Frequently Asked Questions

Here are the answers to some common questions about audits in California:

  • How long can California collect back taxes? The FTB can collect taxes due as far back as 20 years ago, or even longer if they assess additional fees. For example, if you have unpaid taxes from 2005, the FTB would have until 2025 to collect. However, if they audited you in 2015 and sent an NPA, the assessment resets the 20-year statute of limitations, giving them until 2035 to collect the unpaid taxes from 2005.
  • What forms do I need to file taxes? California FTB Form 540 is the resident income tax return. The CA FTB tax forms for businesses vary depending on the type of business entity you have.
  • How far back can an audit go? The FTB can generally go back four years from the original due date. However, if you didn't file a return for the year in question, they can audit at any time. Similarly, if your state taxes could change because of federal adjustments, you have six months to notify the state. The FTB then has two years to issue an assessment. If you wait longer than 6 months, the FTB has four years. There's no limit if you don't notify them at all.
  • What happens if a CA FTB audit finds overpayment? If the result of an audit is that you overpaid, you'll receive a refund.
  • What should taxpayers do if they're audited? Consult with a professional tax audit advisor if you get a notice of audit.

Get Audit Advisory Services From SD Mayer

If you live or own a business in California and need audit advisory services, SD Mayer & Associates is here to help. We offer a holistic approach to financials and provide comprehensive support beyond audits. Our personalized services and strong communication can help you make strategic financial choices to put yourself in the best position tax-wise and maintain compliance with laws and regulations.

Contact SD Mayer today to learn more about how we can support you.

 

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