California FTB Notice Notice of Proposed Assessment (FTB 5830)

FTB 5830 is California’s Notice of Proposed Assessment — it’s FTB telling you they’ve audited your return (or used third-party data) and believe you owe additional state income tax. The notice specifies the amount of additional tax, penalties, and interest proposed. It’s serious because it starts a formal legal clock: you have 60 days from the notice date to file a written protest or the assessment becomes final.

Once FTB 5830 becomes final, the proposed amount converts into a legal obligation. FTB can then initiate collection — liens, levies, wage garnishments. The 60-day protest window is your last administrative remedy before paying or litigating in court. After the protest deadline passes without a timely response, FTB issues a Demand for Payment.

Many people confuse FTB 5830 with earlier audit correspondence. This is not a request for information. It’s the result. FTB has made its determination. Your response is now a formal legal protest, not a routine document submission.

Your protest must be in writing and must be received by FTB’s Protest Unit within 60 days of the FTB 5830 notice date — not the date you received it. Mail your protest to the Protest Unit address shown on the notice, using certified mail so you have a delivery confirmation. The protest must identify the tax years at issue, state that you’re protesting the assessment, and explain why you believe FTB’s position is wrong.

A strong protest does more than say ‘I disagree.’ It provides specific legal and factual arguments: which deductions were properly claimed, what the correct income figure is, why a penalty shouldn’t apply, and what documentation supports your position. Attach that documentation to the protest. Vague protests without supporting documents give FTB’s Protest Unit nothing to work with.

Under California Revenue and Taxation Code Section 19041, FTB’s Protest Unit must issue a determination within a reasonable time. The process typically takes six to eighteen months depending on complexity. During a pending protest, FTB’s collections division generally holds levy actions — though interest continues to accrue.

FTB 5830 will itemize the penalties proposed alongside the additional tax. The most common is the accuracy-related penalty under California Revenue and Taxation Code Section 19164 — it’s 20% of the additional tax if FTB determines you underpaid due to negligence, disregard of rules, or a substantial understatement. A ‘substantial understatement’ is defined as understating income by more than $5,000 or 10% of correct tax, whichever is greater.

If FTB believes the underpayment was intentional — fraud — the fraud penalty is 75% of the underpaid tax under Revenue and Taxation Code Section 19164. This is rare in civil audits but not unheard of in situations involving repeated misrepresentations or obviously fabricated deductions. FTB has to prove fraudulent intent by clear and convincing evidence, a higher bar than mere negligence.

Penalties in FTB 5830 are negotiable. You can request penalty abatement alongside your protest. FTB can waive accuracy-related penalties if you demonstrate reasonable cause — reliance on a qualified tax professional, a novel legal question, or unusual circumstances. We include penalty abatement arguments in every protest we file where the underlying facts support it.

California’s standard assessment limitation period is four years from the later of the return due date or the actual filing date. An FTB 5830 issued for a tax year outside that four-year window is generally barred — unless an exception applies. The exceptions are significant and frequently invoked by FTB.

The limitations period extends to six years if you understated gross income by more than 25% under Revenue and Taxation Code Section 19057. For fraudulent returns or returns that were never filed, there’s no limitations period at all. FTB can assess those at any time. if you filed an amended federal return and FTB didn’t receive notification within six months, the California statute may remain open under Revenue and Taxation Code Section 19059.

If you receive an FTB 5830 for a year you think is time-barred, raise the statute of limitations argument in your protest — but do it carefully. You need to confirm the return was actually filed, identify the exact filing date, and determine whether any exceptions apply. We pull IRS transcripts and FTB account records to nail down these dates before relying on a statute argument.

First, file a protest within the 60-day window regardless of whether you can pay. Inability to pay doesn’t reduce the amount FTB is proposing, but it doesn’t affect your right to contest the assessment either. Protest and payment are separate issues. File the protest to preserve your rights while you figure out the money.

After the protest is resolved — whether through agreement, modification, or denial — you’ll know the final amount owed. At that point, payment options include full payment, installment agreements (FTB Form 3567), or, if the balance is genuinely uncollectable based on your financial situation, a currently-not-collectible designation or an Offer in Compromise under Revenue and Taxation Code Section 19443.

Interest is the thing that makes delay expensive. California’s interest on unpaid assessments runs from the original due date of the return, not from the date FTB 5830 was issued. By the time a proposed assessment finalizes and you enter a payment plan, you may be paying interest that’s been accruing for two or three years. Resolving the underlying dispute as quickly as possible — even at a compromise amount — is often the better financial outcome than a prolonged protest.