Understanding State Tax Allocation for Equity Compensation
How a state taxes your equity compensation depends on the type of award, where you lived when the income was recognized, and where you worked while you earned it. The federal rules are the starting point. The IRS treats options granted under an incentive stock option (ISO) plan or an employee stock purchase plan (ESPP) as statutory stock options and all other options as nonstatutory (IRS Topic 427), and no income is recognized when you exercise an ESPP option (IRS Form 3922 instructions). Restricted stock units (RSUs) are taxed when they vest, in the same way as restricted stock under Internal Revenue Code section 83(a); the Franchise Tax Board’s Chief Counsel Ruling 2014-01 explains how California applies that rule.
States then apply their own rules, and those rules do not all follow the federal treatment. Equity awards are therefore not always taxed like salary. In California, the spread on a nonstatutory option and the value of vested RSUs are wages, but an ISO or ESPP does not produce wage income at exercise (FTB Publication 1004). Pennsylvania taxes ISOs the same way as other options, at exercise (Pennsylvania Personal Income Tax Guide).
Cross-State Moves and Income Sourcing
The main complication arises if you relocate between the grant date and the date your equity vests or is exercised. California, New York and Pennsylvania each tax a nonresident on the share of equity income that relates to work performed in that state. Where you lived on the grant date does not control. If you are a resident of one of these states when the income is recognized, that state taxes all of it (FTB Publication 1004; New York rule, section 154.6; Pennsylvania guide).
California
California requires a reasonable allocation and describes a workday ratio as one reasonable method: California workdays divided by total workdays over the allocation period. For nonstatutory options and ESPPs the period runs from grant to exercise, and for RSUs it runs from grant to vest.
Example: The FTB’s own example involves an employee granted options while living in Texas who was later transferred to California; with 700 of 1,000 workdays in California, California taxed 70 percent of the exercise income (FTB Publication 1004).
For ISOs, a nonresident who sells in a qualifying disposition is not taxed by California on the gain, while a disqualifying disposition is treated like a nonstatutory option exercise. Publication 1004 was last revised in January 2015, and Chief Counsel Ruling 2014-01 applies only to the taxpayer who requested it, so check for newer FTB guidance before relying on either.
New York
Under the Department of Taxation and Finance’s rule on stock options and restricted stock (20 NYCRR 132.24), a nonresident has New York source income if the nonresident performed services in New York for the granting company at any time during the allocation period. For ISOs, ESPPs and nonstatutory options without a readily ascertainable fair market value, that period runs from the grant date to the date the option first becomes exercisable, not to the exercise date, and workdays after that date are not counted. For restricted stock without a Section 83(b) election, it runs from receipt of the stock to the date it substantially vests (or earlier if your services end or you sell the stock).
For ISOs and ESPPs the rule also reaches the gain on sale: the compensation portion is the lesser of the exercise spread and the gain realized, and it is sourced with the same workday fraction. Appreciation after exercise is investment income and is not New York source income for a nonresident.
Pennsylvania
Pennsylvania taxes nonresidents only on Pennsylvania-source compensation. Options earned while working in Pennsylvania remain taxable there even if you exercise them after moving, and if you worked in several states the income is apportioned by time worked in Pennsylvania (Pennsylvania guide; 61 Pa. Code section 109.8).
Credits for tax paid to another state
If a state taxes income that another state also taxes, a credit may be available. California, for example, may allow an Other State Tax Credit on Schedule S when the same income is taxed by California and another state (FTB Publication 1004).
Alternative Minimum Tax (AMT) Considerations
If you hold ISOs, the alternative minimum tax (AMT) can apply. Exercising an ISO does not create regular taxable income (IRS Topic 427), but the difference between the stock’s fair market value at exercise and the exercise price is generally an AMT adjustment, which you report on IRS Form 6251, line 2i.
California has its own AMT, reported on Schedule P (540), with ISOs on line 10. Under FTB Publication 1004, the adjustment is made in the year of exercise unless you sell the stock that year, your AMT basis in the shares increases by the adjustment, and a credit for prior-year AMT may be available (FTB form 3510). For a nonresident, California includes only the portion of the adjustment tied to California workdays from grant to exercise. Plan for AMT at both the federal and state level when you exercise.
Key Takeaways for Remote Workers
If you work remotely or are assigned to an out-of-state corporate office, income sourcing rules can become particularly intricate. Each state defines what counts as a workday in that state. New York’s rule, for example, refers readers to 20 NYCRR 132.18 for that definition. Because multi-state tax obligations depend heavily on work days, grant dates, and specific state allocation formulas, it is strongly recommended to consult with a qualified CPA or tax advisor to navigate potential exposure and ensure accurate tax withholding.
State-Specific Exceptions: Pennsylvania Tax Treatment
State tax rules can also deviate significantly from federal classifications. For example, Pennsylvania generally does not recognize federal Incentive Stock Option (ISO) treatment. Instead, Pennsylvania taxes ISOs similarly to Non-Qualified Stock Options (NSOs), triggering taxable income upon exercise regardless of whether the exercise creates a federal AMT preference item.
The Pennsylvania Department of Revenue’s Personal Income Tax Guide says Pennsylvania draws no distinction between qualified and nonqualified options. Options are taxable as compensation on the earliest of the exercise date (unless the stock is subject to substantial restrictions), the date those restrictions lapse, or the date of sale, and Pennsylvania has no equivalent of the federal Section 83(b) election. The taxable amount is the stock’s value at exercise minus the price paid, and that amount is added to your basis for a later sale.
The guide also says Pennsylvania has no provisions separating qualified options from options granted under an ESPP, so confirm with the Department or a tax professional how ESPP shares are taxed before assuming the federal ESPP rules apply.
Sources
- IRS Topic 427, Stock options
- IRS Form 3922 instructions for employees
- IRS Form 6251, Alternative Minimum Tax
- California FTB Publication 1004, Equity-Based Compensation Guidelines
- California FTB Chief Counsel Ruling 2014-01
- California Schedule P (540), Alternative Minimum Tax (2024)
- New York Department of Taxation and Finance, stock options and restricted stock rule (20 NYCRR 132.24)
- Pennsylvania Department of Revenue, Personal Income Tax Guide: Gross Compensation
- 61 Pa. Code section 109.8
This article is for general educational purposes and is not tax advice for your specific situation. State rules change, so confirm current guidance for your state before you file.