Sales Tax and Use Tax Audits in California: What Business Owners Need to Know

Marc Boulanger • May 2, 2025

Introduction: A Sales Tax Audit in California Is No Joke

If you run a business in California that collects or remits sales tax, you may someday face a knock from the California Department of Tax and Fee Administration (CDTFA) — and it often doesn’t come with much warning.


Whether you’re a retailer, contractor, service provider, or e-commerce seller, a sales or use tax audit can expose your business to massive back assessments, penalties, and long-term consequences if not handled properly.


In this guide, we’ll walk you through exactly how California sales and use tax audits work, what triggers them, and what Orange County business owners can do to protect themselves.


πŸ“š What Are Sales and Use Taxes in California?


βœ… Sales Tax:

Charged on tangible personal property sold at retail in California. Collected by the seller, remitted to the CDTFA.


βœ… Use Tax:

Applies to out-of-state purchases used, stored, or consumed in California when sales tax wasn’t paid at the time of sale (e.g., online purchases, equipment, contractor tools).


🧠 What Is a CDTFA Audit?

A CDTFA audit is an in-depth review of your business’s books, records, and tax filings to determine if you’ve:

  • Underreported taxable sales
  • Over-claimed exempt sales
  • Failed to self-report use tax
  • Failed to remit collected tax to the state


πŸ” What Triggers a Sales Tax Audit in California?


Trigger Description
Late or missing filings Missed sales tax returns (Form CDTFA-401-A)
Large exempt sales Claiming high volume of non-taxable sales without documentation
Mismatch with income tax filings Gross sales on sales tax return don’t match what’s on your FTB or IRS returns
Industry audit sweep CDTFA routinely audits businesses in high-risk sectors
Tips from former employees or customers Anonymous reports trigger a surprising number of audits
Prior noncompliance Once audited, you’re more likely to be audited again


⚠️ High-Risk Industries in California

The CDTFA frequently audits businesses in:

  • Restaurants and food service
  • Construction and contractors
  • Auto repair and dealerships
  • Retail and convenience stores
  • Medical equipment sales
  • Cannabis dispensaries
  • E-commerce businesses with mixed-taxable inventory


βœ… How to Prepare for a Sales or Use Tax Audit


βœ… 1. Gather All Sales and Purchase Records

You’ll need:

  • Invoices and receipts
  • POS summaries and Z-tapes
  • Bank statements and credit card reports
  • Purchase orders and vendor statements
  • Sales tax return copies (CDTFA-401-A)


βœ… 2. Identify and Support Exempt Sales

The most common issue in sales tax audits is unsupported exemptions.


Make sure you have:

  • Resale certificates (BOE-230)
  • Out-of-state shipping records
  • Documentation for labor-only charges


βœ… 3. Review Use Tax Compliance

If you purchased items from out of state or online:

  • Did you pay use tax voluntarily?
  • Did you report it on your sales tax return?


The CDTFA often assesses use tax on equipment or goods brought into California from vendors who didn’t charge tax.


βœ… 4. Avoid Red Flags in Recordkeeping

Auditors don’t like:

  • Rounded numbers with no documentation
  • Inconsistent reporting across sales tax, income tax, and bank deposits
  • Commingled funds or poor sales breakdowns


πŸ›‘ What Happens If You Fail a Sales Tax Audit?

Consequences may include:

  • Back assessments for unreported taxable sales
  • 25% penalty for negligence
  • 10% penalty for late payment
  • Daily compounded interest
  • Referral to the FTB for collection if unpaid


πŸ‘‰ What the FTB Can and Can’t Legally Seize


🧾 What to Do If You Disagree with the Audit Results

You have the right to:

  • Request a redetermination
  • Appeal to the CDTFA Office of Tax Appeals (OTA)
  • File a claim for refund, if overpaid


Timing is critical — most appeals must be filed within 30 days of the notice.


🧭 How Boulanger CPA Helps Orange County Businesses

We help retailers, contractors, service providers, and e-commerce sellers across Irvine, Anaheim, Santa Ana, Fullerton, and beyond:

  • Prepare for CDTFA audits
  • Respond to audit notices and document requests
  • Defend against unreasonable assessments
  • Request audit reconsideration or appeal
  • Prevent FTB collections from CDTFA referrals


πŸ“ž Call 657-218-5700
🌐
www.orangecounty.cpa

Frequently Asked Questions

  • What triggers a CDTFA sales tax audit?

    Common triggers include late filings, high exempt sales, income mismatch, and tips from employees or customers.

  • Can I get penalized for unpaid use tax?

    Yes. The CDTFA can assess tax, penalties, and interest on unreported purchases from out-of-state vendors.

  • What if I can’t pay what they assess?

    You may qualify for a payment plan, Offer in Compromise (if referred to FTB), or hardship relief.

  • Can I appeal a CDTFA audit decision?

    Yes. You can request a redetermination and appeal to the Office of Tax Appeals (OTA) if needed.


ο»ΏπŸ“£ About the Author


Marc Boulanger, CPA is the founder of Boulanger CPA and Consulting PC, based in Orange County, California.


With over a decade of experience helping individuals and businesses resolve serious IRS and State tax issues, Marc specializes in tax resolution strategies including Offers in Compromise, wage garnishment relief, and back tax compliance.


He is licensed as a Certified Public Accountant in both California and Oklahoma, and has a proven track record of helping clients settle complex tax debts and regain financial stability.


πŸ“ Learn more at www.orangecounty.cpa or call (657) 218-5700.


Marc The CPA's Tax Blog

A safe with the word ftb on it
By Marc Boulanger May 2, 2025
If the FTB is coming after your business, CDTFA or EDD may be involved too. Learn what triggers state tax enforcement and how to resolve it fast in California.
A person is holding a piece of paper that says payroll tax problems with the edd and ftb
By Marc Boulanger May 1, 2025
Behind on California payroll taxes? Learn how to resolve problems with the EDD and FTB, and how Orange County businesses can avoid enforcement and audits.
A police officer is holding a sign that says ftb
By Marc Boulanger May 1, 2025
Owe back taxes? Learn what the California Franchise Tax Board can legally seize — and what they can’t — and how Orange County taxpayers can protect their assets.
A man in a suit and tie stands in front of an orange county cpa guide sign
By Marc Boulanger April 30, 2025
Wondering how much the IRS will settle for? Learn how settlement amounts are calculated and how Orange County taxpayers can qualify for real tax relief.
Picture of an FTB tax lien hanging on a wall.
By Marc Boulanger April 30, 2025
California tax liens don’t go away on their own. Learn how long an FTB lien stays on your record and how Orange County taxpayers can remove it.
By Marc Boulanger April 30, 2025
Introduction: If You Wait, the FTB Won’t When you owe California back taxes, the Franchise Tax Board (FTB) doesn’t hesitate to collect. And one of their most disruptive tools is the bank levy — a legal action that allows the FTB to freeze and seize funds directly from your bank account without warning. But here’s the good news: You can stop an FTB bank levy — if you act early enough. In this guide, we’ll walk you through exactly how FTB levies work, what warning signs to watch for, and what Orange County taxpayers can do to prevent the FTB from emptying their accounts. πŸ’£ What Is a Bank Levy? A bank levy is when the FTB sends a legal order to your financial institution requiring them to: Freeze your account Send available funds to the FTB Do it without court involvement Unlike a lien (which is a claim), a levy actually takes your money. 🚨 What Triggers an FTB Bank Levy? You may be at risk for a bank levy if: You have unpaid California taxes You ignored FTB notices You missed a Demand for Payment You failed to respond to a Notice of Proposed Assessment (NPA) You defaulted on a payment plan or prior arrangement πŸ‘‰ What Happens If You Ignore FTB Notices? 🧾 Common Warning Signs You’re About to Be Levied Demand for Tax Return (DFTR) Notice of Proposed Assessment Final Notice Before Levy FTB collection calls or wage garnishment notices Prior levies or liens filed on your account πŸ‘‰ FTB Collections Process: A Guide for California Taxpayers πŸ“ How Fast Can It Happen? The FTB does not require a court order to levy your bank account. Once your account is flagged for collection: A Final Notice Before Levy is issued You may have as little as 30 days (or less) Once the bank receives the levy, the funds may be frozen immediately πŸ’‘ Can I Stop an FTB Bank Levy Once It Starts? Yes — but it becomes harder. Your best chance is to prevent it entirely by taking action during the notice period. βœ… How to Stop a Bank Levy Before It Starts βœ… 1. Open and Read Every FTB Notice Even if it’s scary or confusing, you must read what the FTB sends you. If you don’t understand it, call a CPA or tax professional — not the FTB directly. πŸ‘‰ Received a Notice from the FTB? Here’s What It Means βœ… 2. File Any Missing Tax Returns Non-filers are high-risk levy targets. The FTB may file a Substitute Return on your behalf (with inflated income and no deductions) and then pursue collections. πŸ‘‰ How to Get Back Into Compliance with the FTB βœ… 3. Contact a CPA to Request a Hold on Collections If your levy hasn’t hit yet, a tax professional can often: Contact the FTB on your behalf Request a temporary hold Submit financial disclosures Buy you time to set up a resolution βœ… 4. Request a Payment Plan (Installment Agreement) Payment plans can stop the FTB from moving forward with a bank levy — especially if submitted before the levy date. πŸ‘‰ FTB Offer in Compromise vs Installment Agreement – Which Is Better? βœ… 5. Qualify for a Hardship Deferral If paying anything would create financial hardship, you may be able to request temporary suspension of collections . πŸ‘‰ How to Qualify for a California FTB Hardship Deferral βœ… 6. Submit an Offer in Compromise (OIC) If you truly can’t pay and never will, you may qualify to settle your debt. If an Offer is pending, the FTB may delay enforcement until it’s reviewed. πŸ‘‰ FTB Offer in Compromise Success Rates & Mistakes to Avoid πŸ›‘ What NOT to Do if You’re Facing an FTB Levy ❌ Don’t Move Your Money Around The FTB can trace financial activity and issue multiple levies to different institutions. ❌ Don’t Call the FTB Without Representation What you say may limit your options later — or trigger additional enforcement. ❌ Don’t Assume It Will Go Away The FTB will not “give up.” Even small balances can trigger bank levies and liens. 🧭 How Boulanger CPA Helps Orange County Taxpayers We help clients in Santa Ana, Irvine, Anaheim, Tustin , and throughout Orange County: Identify levy risk based on notices or transcripts Contact the FTB to stop pending levies Set up compliant Installment Agreements or Offers File missing returns Protect wages and bank accounts from enforcement πŸ“ž Call 657-218-5700 🌐 www.orangecounty.cpa
A man in a suit and tie is sitting at a desk with a sign that says ftb issues specialist
By Marc Boulanger April 29, 2025
The FTB doesn’t operate like the IRS. Learn why hiring a California-based tax professional is the smartest move for resolving state tax debt fast.
A man is sitting at a desk in a home office with a laptop.
By Marc Boulanger April 29, 2025
Owe both the IRS and FTB? Learn how to negotiate federal and California tax debt simultaneously and protect your income. Orange County tax relief guide.
A man is holding a sign that says irs tax relief vs ftb relief key differences
By Marc Boulanger April 28, 2025
IRS tax relief and FTB tax relief are not the same. Learn key differences, eligibility rules, and how Orange County taxpayers can resolve both federal and state debts.
A man is holding a sign that says ftb offer in compromise vs establishment agreement which is better
By Marc Boulanger April 28, 2025
Should you settle your FTB debt or pay over time? Learn the pros, cons, and best options for California taxpayers with help from Boulanger CPA in Orange County.
More Posts