This article reflects federal rules and state rules (with a focus on California, New York, and no-income-tax states like Texas, Florida, Nevada, and Washington) as of June 2026 and covers tax year 2025 (the 2026 filing season). Tax law changes — confirm current figures before you file.
Quick Answer
Your old state can still tax your stock options after you move. For tax year 2025, most states source equity income to where you worked during the vesting period — not where you live when you exercise or sell. So a move to a no-tax state rarely erases the old state’s claim on options you earned there.
Many people believe that crossing a state line the day before they exercise wipes out their old state’s tax. It does not. The state where you performed the work that earned those options keeps a share of the income, and aggressive states like California will track you down years later. The gap between what people expect and what the law says is where five-figure surprise bills come from.
The stakes are real and growing. With remote and hybrid work now standard, the IRS reports that equity compensation is a top audit focus, and state agencies share wage and brokerage data across lines. Here is what this guide gives you:
- 💸 How NQSOs, ISOs, and RSUs each get taxed when you cross a state line, with the exact federal trigger for each.
- 🧮 The “allocation ratio” math states use to claim your income — copied step by step so you can run your own numbers.
- 🗺️ Why moving to Texas, Florida, Nevada, or Washington helps with future growth but not with already-earned income.
- 🛡️ How the other-state tax credit stops double taxation — and the one trap (California–New York ISOs) where it fails.
- ⏰ The forms, deadlines, and quarterly-payment moves that keep you out of penalty territory.
Which Situation Applies to You?
The answer depends on what kind of equity you hold and when you moved relative to your grant, vest, and exercise dates. Use this to jump to the part that fits you.
- You hold NQSOs and moved before exercising: Your old state taxes the spread based on workdays from grant to exercise. See the NQSO section.
- You hold ISOs and moved before exercising: Federal AMT may hit at exercise, and a few states (CA, CO, CT, IA, MN) charge their own AMT. See the ISO section.
- You hold RSUs and moved mid-vest: Each vest is sourced by workdays from grant to that vest date. See the RSU section.
- You moved to a no-income-tax state (TX, FL, NV, WA, TN, SD, WY, AK, NH): You escape tax on future growth, not on income earned while working in the old state. See the no-tax-state section.
- You moved between two taxing states (e.g., CA to NY): Both may claim a share; the other-state tax credit usually prevents double tax. See the double-taxation section.
If your situation spans several of these — say, ISOs and RSUs, or two moves in three years — read each section that applies. Equity sourcing across states is one area where one size never fits all, and the consequence of guessing is a bill plus penalties.
The Core Rule: States Tax Where You Earned It, Not Where You Live
The single most important idea in this entire topic is this: equity compensation is pay for work, and pay is taxed by the state where the work happened. When your employer hands you stock options or RSUs, it is paying you for services. States treat that the same way they treat salary — they look at where you sat and worked during the period you earned the award, not where you happen to live on the day you cash out.
This is called sourcing. The income is “sourced” to the state where you performed the services that earned it. California spells this out in FTB Publication 1004, its official guide to stock options, which states that nonresidents must allocate to California the portion of compensation tied to services performed in the state under Cal. Code Regs. tit. 18, §17951-5. New York, New Jersey, and most other taxing states follow the same logic through their own rules.
The consequence of missing this rule is steep. If you move from a high-tax state and assume your options are now “free,” you may skip a required nonresident return and underpay by tens of thousands of dollars. The state later matches your federal W-2 equity income to its records, sends a bill, and adds interest plus penalties. Because years often pass between grant and exercise, the bill can arrive long after you thought the issue was closed.
Here is the rule in action. Maria works four years in San Francisco, earns a grant, then moves to Austin and exercises a year later. She assumes Texas residency means no state tax. But California allocates a share of her exercise income based on the California workdays during the grant-to-exercise period, and bills her as a nonresident. The common misconception — “I live in a no-tax state now, so I owe nothing” — costs Maria a surprise five-figure California bill.
What you should do about it: before you exercise or before a vest lands, map out your grant, vest, and exercise dates against the states you lived in. If any of that period was spent working in a taxing state, plan to file a nonresident return there and set aside cash for the bill. Doing this before you pull the trigger is the difference between a planned cost and a penalty.
How the Allocation Ratio Works (The Math Every State Uses)
Most states that tax trailing equity income use a fraction called the allocation ratio to decide how much of your income they get. The idea is simple: they tax the share of the income that matches the share of the earning period you spent working in their state. The formula, drawn straight from FTB Publication 1004, is:
[ \text{State-taxable income} = \text{Total income} \times \frac{\text{In-state workdays during the period}}{\text{Total workdays during the period}} ]
The “period” depends on the award type. For NQSOs and ISOs, it runs from the grant date to the exercise date. For RSUs and restricted stock, it runs from the grant date to the vesting date, as explained in this California equity guide. Get the period right and the rest is arithmetic.
The consequence of using the wrong period is a wrong number on your return. If you accidentally measure to the sale date instead of the exercise or vest date, you can overstate or understate the in-state share and either overpay or invite an audit. The period closes when the income is recognized for compensation purposes, not when you finally sell the shares.
Worked example with real figures. Suppose your NQSO spread at exercise is $200,000. Over the grant-to-exercise period you logged 500 total workdays, of which 250 were in California. Your California allocation ratio is 250 ÷ 500 = 50%. California taxes $100,000 of the spread as California-source income, and at roughly the 9.3% bracket for tax year 2025 that is about $9,300 of California tax — even if you live in Texas on exercise day.
A common misconception is that “workdays” means calendar days. It does not — it means days you actually worked, which is why people use total business days and subtract weekends, holidays, and PTO when a precise count matters. What you should do: pull your payroll calendar, your moving date, and your grant agreement, then count workdays in each state for the exact period. Keep that worksheet — it is your defense if the state ever asks.
NQSOs (Nonqualified Stock Options) Across State Lines
Nonqualified stock options, or NQSOs, are options that do not get special tax treatment under the tax code. The federal trigger is exercise: the moment you exercise, the spread between the fair market value and your strike price becomes ordinary wage income, reported on your W-2 and subject to income tax, Social Security, and Medicare.
For state purposes, the income is sourced over the grant-to-exercise window using the allocation ratio. So if you worked in a taxing state for part of that window, that state claims its slice no matter where you live at exercise. The consequence of ignoring this is a missed nonresident return in your old state and a later notice with penalties.
Mini-scenario: David is granted NQSOs while working in New York, then moves to Florida and exercises 18 months later. New York treats the grant-to-exercise spread as New York-source income for the workdays he spent in New York, and he must file a New York nonresident return (Form IT-203) even though Florida has no income tax. The misconception that “Florida has no income tax, so I’m done” leaves David exposed to New York.
What David should do: file the New York nonresident return for the year of exercise, report only the New York-allocated share of the spread, and keep his relocation records. Because Florida has no income tax, there is no double-tax problem here — he simply owes New York its share and nothing to Florida.
ISOs (Incentive Stock Options) and the AMT Trap
Incentive stock options, or ISOs, get favorable federal treatment: if you hold the shares long enough, the gain can be taxed at long-term capital gains rates instead of ordinary rates. But there is a catch at exercise — the spread becomes a preference item for the Alternative Minimum Tax (AMT), a parallel federal tax that can apply even though no cash changed hands.
State treatment of ISOs has two layers. First, the bargain element is sourced over the grant-to-exercise period like any option. Second, AMT matters: most states do not have their own AMT, but California, Colorado, Connecticut, Iowa, and Minnesota do. If you exercise ISOs while living in one of those five states, you may owe a state AMT surcharge on the spread; if you live in any of the other 45 states, you avoid that extra state-level hit.
The consequence of overlooking AMT is a surprise federal (and sometimes state) bill in a year you received zero cash. People exercise large ISO blocks, sell nothing, and then owe AMT on paper gains — a classic and painful mistake, especially if the stock later drops.
Mini-scenario: Priya exercises ISOs after moving from Minnesota to Nevada. Federal AMT applies based on the spread, but because Nevada has no income tax and no state AMT, she avoids any state-level AMT. Had she exercised while still in Minnesota, she would have faced Minnesota’s AMT on the spread. The timing of her move directly changed her state outcome.
What Priya should do: model the federal AMT before exercising (Form 6251), consider spreading exercises across years to stay under the AMT exemption, and time large exercises for after she has genuinely established residency in the no-AMT state. The deadline that matters is December 31 of the exercise year — AMT is set by when you exercise, not when you sell.
RSUs (Restricted Stock Units) Mid-Vest
Restricted stock units, or RSUs, are not technically options — there is no strike price and nothing to “exercise.” But searchers lump them in, and the move-states rules are nearly identical, so they belong here. The federal trigger is vesting: when RSUs vest, the full fair market value of the shares becomes ordinary wage income on your W-2.
For states, each vest is sourced over the grant-to-that-vest-date period using the allocation ratio. Because RSUs usually vest in tranches over several years, a single move can leave you owing your old state on the early vests and your new state on the later ones. The consequence of assuming the whole award follows your current address is an underreported old-state return.
Real-world example from a documented case study: a senior engineer moved from San Francisco to Austin in August 2024 with 1,600 unvested RSUs on a 2022 grant. He assumed Texas residency meant zero state tax on future vests. The work-source allocation trap meant California still claimed roughly $34,000 of tax across 2024–2026, and he avoided a §19136 underpayment penalty only by setting up California Form 540-ES quarterly payments.
Mini-scenario: Lena holds RSUs granted in California that vest over four years; she moves to Washington after year two. California sources the first two years of each vest’s value to California (the workdays she spent there), while the post-move workdays are Washington-source — and Washington has no income tax. The misconception that “Washington has no tax, so my RSUs are free” ignores the California-earned portion.
What Lena should do: for each vest after her move, calculate the California allocation ratio, file California Form 540NR as a nonresident, and pay California quarterly estimates if withholding falls short. She should confirm her employer’s payroll is correctly splitting state withholding, because many do not.
Moving to a No-Income-Tax State
Moving to a state with no income tax — Texas, Florida, Nevada, Washington, Tennessee, South Dakota, Wyoming, Alaska, and New Hampshire (which taxes only certain investment income) — is the most popular equity-tax strategy, and it genuinely works, but only for the right income. It removes the new state’s tax on everything going forward. It does not remove your old state’s claim on income you earned while working there.
Here is the clean line: a no-tax state shelters future appreciation and any income sourced to days you actually worked there, but the grant-to-exercise (or grant-to-vest) workdays in your old state remain taxable by that old state, as confirmed in this stock options tax guide. The longer you keep working — and earning new equity — in the no-tax state, the smaller your old state’s allocation becomes over time.
The consequence of misunderstanding this is the most common surprise in the whole topic: people sell or exercise the day after arriving in Texas and assume zero state tax, then get a California or New York nonresident bill. Moving helps, but the clock matters — you reduce the old-state share by extending the non-old-state portion of the earning period, not by the calendar trick of crossing the line right before a liquidity event.
What you should do: move early in the vesting cycle, not the week before exercise; document a genuine change of domicile (driver’s license, voter registration, home, time present); and remember that gains after exercise — true capital gains on shares you already own — are generally taxed only by your new state of residence. That is where the no-tax state truly pays off.
Double Taxation and the Other-State Tax Credit
When you move between two taxing states, both may claim a share of the same equity income — your old state by sourcing and your new state by residency. The fix built into the system is the other-state tax credit: your resident state gives you a credit for income tax you paid to the other state on the same income, so you are not taxed twice.
Most state pairs handle this cleanly. If you owe California as a nonresident on the sourced share and you now live in a state that taxes residents, your new home state typically grants a credit for the California tax, as New York does for California tax. The consequence of forgetting to claim the credit is paying full tax twice — a costly, avoidable error.
There is one notorious trap: the California–New York ISO mismatch. As discussed in this practitioner thread, California does not recognize New York’s sourcing rule on ISO discount income and does not grant its residents a credit for New York tax on what California considers California-source income. The result can be genuine double taxation on the ISO bargain element. This is exactly the kind of unsettled, high-dollar situation where a CPA earns their fee.
What you should do: file the nonresident return first, calculate the tax paid there, then claim that amount as a credit on your resident return (for example, California Schedule S or New York Form IT-112-R). Note that California only allows the credit for residents of a short list of states — Arizona, Guam, Oregon, and Virginia — so the direction of the credit varies by state pair.
Three Common Scenarios
These are the three move patterns that show up most often, with the practical result of each.
Scenario 1: California to Texas Before Exercise
You worked in California while earning options, then moved to Texas and exercised later. California claims the workday-sourced share; Texas claims nothing.
| Move Detail | Tax Result |
|---|---|
| Worked 2 of 4 vesting years in California, then moved to Texas | California taxes 50% of the spread as nonresident income on Form 540NR |
| Exercised NQSOs after Texas move | Federal ordinary income on full spread; Texas charges no state tax |
| Sold shares months after exercise | Post-exercise capital gain taxed only by Texas (none) — California share is closed |
Scenario 2: California to New York Mid-Vest (RSUs)
You move between two high-tax states while RSUs are still vesting, so both states want a piece.
| Move Detail | Tax Result |
|---|---|
| RSUs granted in California, vested after New York move | California taxes the pre-move workday share; New York taxes you as a resident |
| Same RSU income claimed by both states | New York grants an other-state credit for California tax to prevent double tax |
| ISOs in the mix (CA–NY) | Possible true double tax on the ISO discount — California denies the reciprocal credit |
Scenario 3: No-Tax State the Whole Time
You earned, vested, and exercised entirely while living and working in a no-income-tax state.
| Move Detail | Tax Result |
|---|---|
| Granted and vested while working in Florida | No state income tax on the equity income at all |
| Exercised NQSOs and sold as a Florida resident | Only federal tax applies; no state return needed |
| No prior workdays in a taxing state | No old-state allocation, no nonresident filing required |
Three Named Examples With the Math
Example 1 — Carlos: NQSOs, California to Texas
Carlos was granted NQSOs in California, worked there 250 of his 500 grant-to-exercise workdays, then moved to Austin and exercised with a $200,000 spread. His California ratio is 50%, so California taxes $100,000. At about the 9.3% rate for tax year 2025, he owes roughly $9,300 to California, files Form 540NR, and owes Texas nothing. The lesson: the move helped his future gains, not the California-earned spread.
Example 2 — Aisha: RSUs, California to Washington
Aisha holds RSUs vesting over four years and moves to Seattle after year two. On a vest worth $80,000, her grant-to-vest period was split evenly, so California sources $40,000 to California. At roughly 9.3%, that is about $3,720 of California tax on that single vest, reported on Form 540NR. Washington’s lack of income tax shelters only the post-move workday share.
Example 3 — Tom: ISOs and the AMT, Minnesota to Nevada
Tom exercises ISOs with a $150,000 spread after establishing Nevada residency. Federally, the $150,000 is an AMT preference item that may trigger AMT on Form 6251. Because Nevada has no income tax or state AMT, Tom owes no state tax on the spread — a result that would have been very different had he exercised while still in Minnesota, which imposes its own AMT.
Mistakes to Avoid
- Assuming a no-tax move erases the old state’s claim. The old state still taxes the workdays you spent there, leading to a surprise nonresident bill plus interest.
- Measuring the wrong period. Using the sale date instead of exercise (options) or vest (RSUs) date skews your allocation and can trigger an audit.
- Skipping the nonresident return. Failing to file in your old state means the agency later assesses tax with penalties once it matches your W-2 equity income.
- Forgetting quarterly estimates. Equity income is often under-withheld, and missing estimates invites underpayment penalties like California’s §19136 charge.
- Ignoring state AMT. Exercising large ISO blocks in California, Colorado, Connecticut, Iowa, or Minnesota can add a state AMT bill you did not plan for.
- Not claiming the other-state credit. Paying both states without claiming the resident credit means paying full tax twice on the same dollars.
- Weak proof of the move. Without driver’s license, voter registration, and presence records, the old state can argue you never truly left and tax everything.
- Trusting payroll to split state withholding correctly. Many employers withhold for only one state, leaving you to fix the allocation and owe a balance.
Do’s and Don’ts
- Do count actual workdays in each state for the exact earning period — it is the foundation of every correct number.
- Do file a nonresident return in your old state when any workdays there fall inside the earning period, to stay compliant and avoid penalties.
- Do set up quarterly estimated payments when withholding falls short, because equity income is routinely under-withheld.
- Do keep relocation records (license, lease, utility bills, travel logs) to prove a genuine change of domicile if challenged.
- Do model AMT before exercising ISOs, since the tax can hit in a no-cash year and ruin your plan.
- Don’t exercise or let a vest land the week before a move and expect the old state’s claim to vanish — timing the calendar does not change sourcing.
- Don’t measure your allocation period to the sale date; it ends at exercise or vest.
- Don’t assume your new resident state automatically credits the old state’s tax — the California–New York ISO case proves it sometimes does not.
- Don’t rely on your employer’s W-2 to allocate states for you; verify the split yourself.
- Don’t ignore a nonresident filing because the dollar amount “feels small” — penalties and interest compound for years.
Pros and Cons of Moving to a Lower-Tax State for Equity
- Pro — future growth is sheltered: appreciation after exercise is generally taxed only by your new state, which can be zero in no-tax states.
- Pro — new equity is cleaner: awards earned entirely after the move source to the low-tax state, shrinking old-state exposure over time.
- Pro — capital gains relief: long-term gains on shares you already hold escape the old state once your nonresident sourcing window closes.
- Pro — compounding benefit: the longer you work in the low-tax state, the smaller the old-state allocation ratio becomes.
- Pro — simpler future filing: once the old-state-sourced awards clear, you may only file one resident return.
- Con — old-earned income still taxed: the old state keeps its workday share, so the move does not retroactively free past awards.
- Con — double-tax risk between taxing states: mismatched credit rules (CA–NY ISOs) can cause genuine double taxation.
- Con — residency audits: high-tax states aggressively challenge departures, demanding proof you truly left.
- Con — added filing complexity: you may juggle a nonresident return, a resident return, and credit forms for several years.
- Con — timing pressure: the benefit depends on moving early in the vesting cycle, which may conflict with career or family plans.
What to Do Next
- Pull your documents now: grant agreements, vesting schedules, your exact move date, and a workday calendar for each state.
- Identify the earning period for each award — grant-to-exercise for options, grant-to-vest for RSUs — and count in-state workdays.
- Run the allocation ratio for every award and estimate the old-state tax due.
- Set up estimated payments (for example, California Form 540-ES) before the next exercise or vest to avoid underpayment penalties.
- File the right returns: a nonresident return in the old state (such as California Form 540NR or New York Form IT-203) and a resident return in your new state, claiming the other-state credit where allowed.
- Call a professional if you hold ISOs, face a CA–NY pairing, have multiple moves, or your equity exceeds roughly $100,000 — a CPA or tax attorney can model AMT and defend a residency position, typically for a few hundred to a few thousand dollars.
This article is educational and is not a substitute for advice from a licensed tax professional about your specific situation. Equity sourcing across states is genuinely unsettled in places, and a confident wrong assumption here is expensive.
FAQs
Does California tax my stock options after I move away?
Yes. For tax year 2025, California taxes the share of option income tied to workdays you spent in California during the grant-to-exercise period, even if you are a nonresident when you exercise. You file Form 540NR.
Can I avoid state tax by moving to Texas before exercising?
Partly. Texas charges no income tax on your future income, but your old state still taxes the portion you earned working there. Moving the day before exercise does not erase that old-state claim.
What period do states use to source RSU income?
Grant date to vesting date. Each RSU tranche is sourced over the time from grant to that specific vest, split by the workdays you spent in each state during that window.
Do I owe two states tax on the same equity income?
Sometimes, but usually offset. Your resident state generally grants an other-state tax credit so you are not taxed twice — except in mismatched cases like California–New York ISO discount income.
Which states have their own AMT on ISO exercises?
California, Colorado, Connecticut, Iowa, and Minnesota. If you exercise ISOs while living in any of these for tax year 2025, you may owe a state-level AMT in addition to federal AMT.
Are RSUs the same as stock options for state tax?
No, but close. RSUs have no strike price and are taxed at vesting, not exercise. The state sourcing method — workday allocation over the earning period — is nearly identical to options.
What form do I file as a nonresident of California?
Form 540NR. You report only the California-sourced share of your equity income on California’s nonresident return, supported by your workday allocation worksheet.
When is the income taxed — at exercise, vesting, or sale?
At exercise for options, at vesting for RSUs. NQSO and ISO spreads are recognized at exercise; RSU value is recognized at vesting. Later sales create separate capital gains.
Does moving help with capital gains on shares I already own?
Yes. Appreciation after exercise is generally taxed only by your current resident state, so a no-tax state shelters that post-exercise gain.
Will my employer handle the multistate withholding?
Often not fully. Many employers withhold for only one state, so you may need to file estimates and reconcile the allocation yourself to avoid a balance due and penalties.
Can the old state audit my residency move?
Yes. High-tax states like California and New York aggressively challenge departures, so keep proof of your move — license, voter registration, lease, and days-present records.
What happens if I skip the nonresident return?
You face tax plus penalties. The state matches your federal W-2 equity income to its records and can assess the tax with interest and underpayment penalties years later.