California Residency Audits and Equity Income: What the FTB Looks For

The California Franchise Tax Board treats departures by high-income taxpayers as audit triggers, particularly when those departures happen around a liquidity event. A senior IC who “moved to Texas in October” but had $2M of RSUs vest in November will see an audit letter. The FTB wants evidence that the move was genuine, not tax-motivated.

The audit isn’t automatic. The FTB’s Audit Division selects cases based on patterns: departure from California coinciding with large income events, failure to file a California part-year return, maintained California ties post-move, or discrepancies between federal and state returns.

For equity-heavy taxpayers, the audit can be brutal. California claimed residency for 4.5 months of a 12-month window in one prominent case; that fractional residency pulled a $4M equity gain into California tax at 13.3%.

Legal framework

California residency is determined under R&TC §17014 and the administrative-law guidance in FTB Publication 1031. Two tests apply:

Domicile test. Domicile is the place where a person intends to permanently reside. A person can have only one domicile at a time. Changing domicile requires both physical move and intent.

Closest connection test. Even without domicile, a person is a California resident if their closest connections are to California during the tax year.

Both tests are fact-and-circumstances, which means the FTB has wide latitude to argue the other side.

The 20-factor analysis

The FTB’s audit workpapers catalog 20+ factors that indicate connection to a state. No single factor is dispositive, but the overall pattern determines the outcome.

Factors weighed:

Location of residence (where you actually sleep most nights)
Location of spouse and children
Principal place of employment
Driver’s license and vehicle registration
Voter registration
Bank and brokerage account locations
Physician, dentist, and professional service providers
Religious or social organization memberships
Club memberships (gym, country club)
Location of personal possessions (furniture, art, tools)
Safe deposit box location
Attorney and accountant locations
Homestead declaration
Mailing address used for personal correspondence
Homeowner’s exemption on real estate
Location of pets and livestock
Location of family graves
Jurisdiction of estate planning documents
Time spent in each state
Telephone numbers and utilities

A departing taxpayer who moves to Texas but keeps California driver’s license, California bank account, California doctor, and California tax preparer has not convincingly moved. The FTB will weigh those ties against the Texas home and conclude residency remained in California.

The 546-day safe harbor

R&TC §17014(d) offers a limited safe harbor: a taxpayer present in California for 546 days or less over a 2-year period is presumed non-resident. But this only applies to taxpayers whose principal purpose abroad was an employment contract of at least 546 days. It doesn’t help most departing tech employees.

Simply being out of California doesn’t establish non-residency. You have to establish residency somewhere else, and cut ties to California.

Common audit triggers

The FTB auditors look for these patterns:

Liquidity event coinciding with departure. Someone moves in November and has an IPO vest in December. The timing is suspicious. The FTB will ask for flight records, utility bills, and credit card statements to verify physical presence at the new location.

Maintained California real estate. Keeping a California home post-move, even as a rental, is a connection. Some taxpayers maintain California ownership but rent out; the FTB asks why they kept it.

Family remaining in California. Spouse and school-age children staying behind while the taxpayer relocates is a strong indicator of continued California domicile.

Failure to file 540NR. Part-year residents should file Form 540NR showing the California period. Filing only the destination state’s return but no California return triggers an FTB inquiry.

Professional services in California. Continuing with California-based accountant, attorney, or wealth manager after a move is factual evidence of continued connection.

Documenting a clean move

Best practices for documenting a genuine relocation:

File a change-of-address with the USPS on move date
Change driver’s license within 30 days of move
Register to vote in new state
Switch doctor and dentist
Close California bank accounts or note that national banks with branches in both states don’t count either way
Transfer professional services (accountant, attorney)
Move safe deposit box
Update will and estate planning to reflect new domicile
Keep lease or purchase records of new residence
Log days-in-California (some taxpayers use GPS or flight tracker apps)
Don’t visit California for 60+ days in the year of the move

Trailing nexus: what still gets taxed

Even after a clean move, California taxes income that was “earned” in California. For equity compensation, this often means workday allocation:

RSU income. Source based on workdays during the grant-to-vest period that were in California. A grant made 12/1/2021 that vests 12/1/2025 with 1000 California workdays out of 1460 total workdays is 68.5% California-source.

Option exercises. Sourced based on workdays during grant-to-exercise period.

Deferred compensation. Under 4 U.S.C. §114, certain qualified deferred comp is sourced to the state of residence at distribution. Non-qualified deferred comp follows workday allocation.

Capital gains on stock. Generally sourced to state of residence at sale. A departed taxpayer who sells stock from California state is Texas-sourced on gain, assuming clean residency change.

What the audit actually looks like

The FTB opens an audit with a Residency Questionnaire (Form 4600 or similar). The taxpayer answers questions about domicile, residency, days in state, and connections. Responses can trigger requests for:

Credit card statements showing transactions and locations
Flight itineraries
Bank account statements
Employer’s workday records
Vehicle registration records
Utility bills showing residence
School enrollment records for children

The process can take 12-24 months. A finding of California residency in the year of a large equity event can cost $500K-$2M+ in back tax, interest, and penalties.

Settlements and protests

FTB audit findings can be protested through the FTB’s protest division, then appealed to the Office of Tax Appeals. Settlements sometimes reach agreement on partial residency (e.g., 6 months of 12) that reduces the California tax impact.

Legal representation matters. California state-tax specialists often negotiate significantly better outcomes than taxpayers representing themselves.

Frequently asked

If I move to Texas in December, am I California-resident for 11 months? Yes, if you were domiciled in California until December. You file Form 540NR for the part-year California resident period. All income earned during that 11 months is California-taxed.

Does a second home in California trigger residency? Not by itself, but it’s a connection factor. Taxpayers who own California real estate and spend meaningful time there face more scrutiny than those who don’t.

How does §6501 statute apply to California audits? California’s assessment period under R&TC §19057 is generally 4 years from the return filing date, longer than the federal §6501 3-year period. Keep documentation longer for state returns.

What about RSU grants made before I moved to California? Grants made before California residence, vesting during California residence, are allocated based on workday allocation over the full vesting period. Some of the gain may still be California-source even if the grant predates residency.

Does establishing Nevada residency before an IPO work? It can, if the move is genuine and made before the IPO-triggered vest happens. But RSUs that vested in California or had California workdays during the grant period retain California trailing nexus. See the workday allocation article for details.