Most of the time, taxpayers can handle personal income taxes without too much trouble but there are times when a tax attorney can be either a handy resource or a required partner.
For many people, income tax withholding is something that happens automatically: you indicate your tax withholding rate to your employer on a W-4 form for federal taxes and a DE 4 form for California, and the taxes are taken out before you even see your paycheck. If your employer withholds at the correct rate, chance are you’ll end up with a nice refund at tax time.
California’s standard statute of limitations for a CDTFA sales tax audit is three years from the date your return was due or filed, whichever is later — after that window closes, the CDTFA generally cannot assess additional tax for that period.
That three-year rule is the baseline under Revenue and Taxation Code § 6487. But the statute has extended periods that can push the window out significantly, and the clock can be tolled or voluntarily extended. Time can be on your side — but only if you know when the clock runs and what keeps it from running.
The CDTFA has two extended assessment periods: one for substantial understatement of gross receipts, and one for unfiled returns.
Under RTC § 6487(b), if your reported gross receipts for a period were understated by more than 25%, the CDTFA’s assessment window extends to eight years. A business that reported $1.8 million in taxable sales when the actual figure was closer to $2.5 million is in eight-year territory. Auditors who spot a gap in a targeted year will typically work backward to determine whether the pattern holds across earlier periods.
If you failed to file a sales tax return for a period, there is no statute of limitations — the CDTFA can assess at any time. The same applies to fraud. These are the two situations where the clock never starts running.
The limitations period can be extended by a waiver, reset by an amended return, or effectively defined through voluntary disclosure — depending on what you do and when.
Waivers are the most common extension mechanism in practice. When a CDTFA auditor needs more time before the statute expires on a period, they will ask you to sign a Statute of Limitations Waiver — typically extending the period by one to two years. Waivers are not legally required. Whether to sign is a strategic decision that depends on how close the statute is to expiring and what the auditor’s findings look like. If the statute is about to expire on a period the audit hasn’t yet examined, refusing the waiver may effectively close that period. That is worth thinking through with counsel before responding.
Amended returns reset the limitations period for the specific filing period covered. If you file an amended return for Q3 2021, the three-year window runs from the amended filing date — not the original due date. Relevant if you’re considering self-correcting errors.
If you have unreported or underreported sales tax and have not yet been contacted by the CDTFA, voluntary disclosure is an option — but it trades your limitations period rights for reduced penalties and a defined lookback window.
The CDTFA’s Voluntary Disclosure Program allows businesses to come forward, disclose the correct liability, and pay the tax with reduced or waived penalties. In exchange, the CDTFA audits a limited lookback period — often three years — but you waive your right to dispute the period covered. The tradeoff is certainty and reduced cost versus the rights you give up. If the CDTFA has already contacted you, voluntary disclosure is no longer available.
Whether the statute works in your favor depends on which periods are at issue, how those years look, and whether the CDTFA has flagged your account.
If you’re past the three-year window for a period, the CDTFA cannot add it to a current audit without establishing that an extended period applies. Auditors sometimes attempt to characterize transactions as a ‘substantial understatement’ to justify reaching the eight-year lookback. If they can show the 25% threshold is met, all years within that window become fair game.
Even within the limitations period, older records create practical challenges for both sides. Documentation is harder to locate, memories are less precise, and reconstructed records carry less weight. That cuts both ways.
Here’s the actual issue: the statute of limitations is a defense, but you generally have to raise it. The CDTFA is not going to tell you an assessment is time-barred. If an auditor is working years outside the limitations period, the objection has to come from you — ideally in writing, before any findings are issued on those periods.
If an auditor asks you to sign a waiver and a period is close to expiring, consult an attorney before responding.
CDTFA audits often run longer than the three-year period allows, and waiver requests are routine. Most taxpayers sign without thinking about it. But if the period has thin records or is one of the last open years the CDTFA can still reach, signing a waiver keeps a door open that might otherwise close. Refusing is not illegal and does not constitute an admission of anything.
Three years from the date the return was due or filed, whichever is later, under Revenue and Taxation Code § 6487. The period extends to eight years if reported gross receipts were understated by more than 25%. There is no limitation period for unfiled returns or returns tainted by fraud.
No, not unilaterally. The CDTFA extends the period by asking you to sign a waiver. You are not required to sign. The CDTFA can also argue the eight-year period applies if it believes your returns substantially understated gross receipts — but that characterization can be contested on audit or appeal.
Yes, for that specific period. Filing an amended return for a given quarter starts the three-year limitations period running again from the date you filed the amendment. This is a consideration when deciding whether to self-correct an error — doing so reopens the period rather than closing it.
Generally, no — unless the CDTFA can establish that the eight-year period applies (substantial understatement) or that no return was filed. If an auditor attempts to assess a time-barred period, you raise the statute as a defense in writing. The burden shifts to the CDTFA to show that an extended period applies.
If you’ve received a CDTFA audit notice or are trying to understand what years are still open, our overview of California sales tax audit defense covers the process from initial contact through hearing. Book a free 15-minute call to talk through the specific periods in your situation.
CDTFA audits can result in significant assessments — especially if records are incomplete. The direction of the audit is largely set by how you respond to the initial document request. If you’re at any stage of a sales tax audit, a brief review can clarify what you’re facing.
Discuss My Sales Tax Audit → Or call: (619) 378-3138
In small business owner cases, the debtor may not be required to file a separate disclosure statement, provided that the “court determines that adequate information is contained in the [reorganization] plan” (“Bankruptcy Basics, p. 30). With this in mind, small business bankruptcy cases are treated differently than regular bankruptcy cases.