CDTFA Sales Tax Defense

CDTFA sampling audit? Don't pay the extrapolation.

California's Department of Tax and Fee Administration uses sampling methodology to extrapolate alleged underpayments across years — turning a $5,000 sample finding into a $200,000 assessment. Defeating it requires statistical modeling, not just bookkeeping. That's our specialty.

Get a Free CDTFA Review → (408) 287-1888

$5.7M+ extrapolations challenged at Appeals Bureau $700K assessment eliminated (airplane use tax) Negligence penalties struck on appeal

[Image: CDTFA sales tax defense]

Why CDTFA Audits Are Different

It's a statistics problem, not an accounting problem.

CDTFA auditors don't review every transaction. They sample — a week of sales, a month of purchases, a credit-card-to-cash ratio — and extrapolate to the audit period. If you accept their methodology, you accept the assessment.

The defense is to challenge the methodology itself. Build an alternative sampling, model credit-card vs. cash ratios using your actual POS data, demonstrate non-representative sample periods, identify outliers the auditor included. This is what we do.

Most general tax practitioners can't do this work because it requires both tax-controversy expertise and quantitative modeling. Our Enrolled Agent has built and presented statistical models in CDTFA appeals for 40+ years.

[Image: data visualization / statistical analysis]

The Defense Playbook

The five methodology errors we look for in every CDTFA audit.

CDTFA auditors are bound by the Department's own Audit Manual. When they cut corners, the assessment is vulnerable on appeal. These are the issues we've successfully argued at Appeals Bureau.

①

No Reasonableness Check

Audit Manual §0802.70 requires the auditor to use an alternative method to validate any tax deficiency. Auditors routinely skip this step. When they do, the assessment can be challenged on procedural grounds alone.

②

Arbitrary Sample Selection

Sampling only works if the sample is representative. We've seen auditors cherry-pick a single day, or two random months from a multi-year audit, and project a single ratio across the entire period. Non-representative samples are challengeable.

③

Skipped Mark-Up Model

For restaurants and retail, the mark-up model is one of the most reliable indirect methods. When an auditor marks it "NOT USED" without explanation, that's a methodology gap we exploit on appeal.

④

Bank Deposit Analysis Ignored

Bank deposit analysis is the most direct indirect method available. Skipping it while relying on a single-day site test is methodologically backwards — and persuasive evidence of audit overreach.

⑤

Mixed-Ratio Cherry-Picking

Applying different ratios to different quarters within the same audit period — without statistical justification — is one of the most common and most defeatable errors. We've reversed it.

The Win Pattern

When we find these errors, the Appeals Bureau can order a reaudit on a proper basis and strike accuracy/negligence penalties. We've documented both outcomes in multi-million dollar extrapolation cases.

See documented results →

Industries We Defend

Specialized experience in audited industries.

️

Restaurants

POS analysis, comp/void tracking, alcohol-vs-food ratio defense, tip allocation.

Liquor Stores

Markup analysis, inventory shrinkage, ABC license interplay, beverage extrapolation defense.

️

Aircraft & Vehicles

Use-tax challenges, common carrier exemption, interstate commerce defenses.

Retail & Service Businesses

Resale certificate disputes, exempt-sale documentation, service-vs-tangible classification.

Our Process

How we defend a CDTFA audit.

Audit Review

Free consultation. Review CDTFA's audit work papers and proposed methodology.

Counter-Analysis

Build alternative statistical models from your actual data. Identify methodology flaws.

Auditor Negotiation

Present counter-analysis directly to the CDTFA auditor and their supervisor.

Appeal If Needed

Petition Section, Settlement Program, or California Office of Tax Appeals.

Documented Wins

Real CDTFA assessments, defeated.

[Restaurant case]

Restaurant · Appeals Bureau Win

$5.7M Single-Day Extrapolation Defeated

$50K penalty struck
+ reaudit ordered

CDTFA auditor extrapolated a single-day site test across three years to claim $5.7M in unreported sales ($507K tax + $50K negligence penalty). Our appeals brief identified five specific Audit Manual violations. Appeals Bureau ordered a reaudit on a proper basis and struck the $50K negligence penalty entirely.

[Airplane case]

Use Tax

Airplane Purchase Use Tax

$700K eliminated

Successfully defended a sales tax audit on an airplane purchase. Assessment fully eliminated.

FAQ

CDTFA audit questions, answered.

I just got a CDTFA audit letter. What's the deadline?

The initial information request usually gives 30 days. Don't ignore it — but don't blindly comply either. What you submit shapes the entire audit. Call us before you respond.

Why did CDTFA pick my business for audit?

Common triggers include large refund claims, industry-wide sweep audits (restaurants, liquor stores), unusual sales-tax-to-income ratios, anonymous tips, or random selection. Sometimes it's just rotation through their audit pool.

Can I just hire my CPA to handle the audit?

You can, but if CDTFA proposes an assessment that requires statistical defense or appeals, your CPA may not have the expertise. We often get brought in mid-audit when the CPA realizes the methodology challenge is beyond bookkeeping work.

What if I owe — can you negotiate the assessment down?

Yes. Even when there's a genuine underpayment, CDTFA's extrapolation is almost always negotiable. We've reduced assessments by 40-80% in cases where the underlying liability was real but the methodology was overreach.

What's the difference between Petition Section and the Settlement Program?

Petition Section is the formal administrative appeal — strict deadlines, formal hearings. The Settlement Program is a separate negotiated resolution track that's often faster and produces better outcomes for many cases. We assess which path fits your facts.

Free CDTFA Review

The earlier we engage, the more we can defend.

If CDTFA has contacted you — even informally — call us. The first 30 days of an audit shape its trajectory. Free consultation, no obligation.

(408) 287-1888

Request CDTFA Review

We respond within 1 business day.

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