Non-Qualified Stock Options (NSO) in Private Companies

A Non-Qualified Stock Option (NSO) — sometimes called a Non-Statutory Stock Option (NQSO) — is a stock option that does not meet the IRS requirements for Incentive Stock Option (ISO) treatment. That sounds like a second-tier instrument, but NSOs are in fact the more flexible and more commonly used option type: they can be granted to employees, contractors, advisors, board members, and any other service provider. They have no annual grant limits. And for recipients who do not expect to hold shares long-term or who are not employees, the simpler tax structure is sometimes preferable.

The trade-off is straightforward: when you exercise NSOs, the spread between your strike price and the fair market value is immediately recognized as ordinary income — subject to federal income tax, FICA (Social Security and Medicare), and, for California residents, state income tax at rates up to 13.3%. There is no AMT calculation, no holding period for favorable tax treatment at exercise, and no deferral of the income recognition. You owe taxes in the year you exercise, on the full spread, at ordinary income rates.

Who Receives NSOs

Unlike ISOs, which are restricted to employees, NSOs can be granted to any service provider:

• Full-time and part-time employees
• Contractors and consultants
• Advisors (typically on advisory share agreements)
• Board members and independent directors
• Founders receiving equity for services

At private companies, NSOs are particularly common for:

Non-employee advisors. When a startup grants equity to an advisor who is not an employee, those grants are NSOs by law. The advisor receives stock options that vest on a schedule (often over 2 years with a 6-month cliff, rather than the standard 4-year employee schedule) and pays ordinary income tax on the spread at exercise.

Consultants and contractors. If you perform services for a company as a contractor and receive stock options, those options are NSOs. The tax treatment at exercise is the same as for employees, but the income is reported on a 1099-NEC rather than a W-2.

Employees at later-stage companies where the $100,000 ISO limit is exceeded. Any options that vest above the $100,000 ISO threshold automatically become NSOs. See Incentive Stock Options (ISO) in Private Companies for how this limit is calculated.

When reviewing an equity offer, ask explicitly whether your grant is an ISO, an NSO, or a combination. Companies are required to specify this in your grant agreement, but recruiter conversations often blur the distinction. The difference is material for tax planning.

Strike Price and the 409A Requirement

NSO strike prices, like ISO strike prices, must be set at or above the fair market value of the company's common stock on the grant date, as determined by a 409A valuation. Granting NSOs below FMV violates Section 409A and exposes the employee or contractor to immediate income taxation plus a 20% penalty — even before exercise.

See 409A Valuation: What It Is and How It Affects Your Equity for how the FMV determination works and why it matters for your strike price.

The Tax Event at Exercise: How It Works

When you exercise NSOs, you pay the strike price per share to receive actual company shares. At that moment, the spread — FMV at exercise minus your strike price — is taxable as ordinary compensation income.

For employees: The spread is added to your W-2 wages in the year of exercise. Your employer is required to withhold federal income tax, Social Security, and Medicare on the amount. The withholding is typically handled by the company withholding shares equivalent to the tax owed ("sell-to-cover"), though some companies require cash payment.

For non-employees (contractors, advisors): The spread is reported on a 1099-NEC and is subject to self-employment tax (15.3% up to the Social Security wage base, 2.9% above) in addition to ordinary income tax. Non-employees typically receive no automatic withholding — you are responsible for estimating and paying the taxes yourself, including potential quarterly estimated payments.

Example:

You have 10,000 NSOs with a strike price of $3.00. You exercise all of them when the 409A FMV is $15.00.

• Spread: ($15.00 − $3.00) × 10,000 = $120,000 of ordinary income
• Cost to exercise: $3.00 × 10,000 = $30,000
• Federal income tax (at 35% marginal rate, hypothetical): ~$42,000
• California income tax (at ~11% effective rate): ~$13,200
• Total cash outflow to exercise and cover taxes: ~$85,200
• Net shares received (if shares are withheld for taxes): fewer than 10,000

The NSO exercise is a significant cash event, even at a private company where the shares cannot be sold. Unlike ISO exercise, where no federal ordinary income is recognized, NSO exercise requires real cash for both the exercise price and the tax bill.

After Exercise: Capital Gains on Subsequent Appreciation

After you exercise NSOs and receive shares, your tax basis in those shares equals the FMV at exercise — not your strike price. You already paid ordinary income tax on the spread; that amount is your cost basis.

Any further appreciation from the FMV at exercise to the eventual sale price is a capital gain — short-term if you sell within one year of exercise, long-term if you hold for more than one year. Long-term capital gains rates are federally 0%, 15%, or 20% depending on income.

Example (continued): The company IPOs two years after you exercised. Share price at IPO: $35.

• Your basis: $15.00 per share (FMV at exercise)
• Sale price: $35.00 per share
• Capital gain: $20.00 per share × 10,000 shares = $200,000
• Federal long-term capital gains rate (at 20%): $40,000
• California: $200,000 × up to 13.3% = up to $26,600 (California taxes all capital gains as ordinary income)

The total tax picture: ordinary income on the spread at exercise + capital gains tax on appreciation after exercise.

NSOs and QSBS

NSOs can qualify for Qualified Small Business Stock (Section 1202) benefits if the company and holding period requirements are met. The QSBS holding period starts at exercise — the date you receive the shares — not at the grant date.

Updated QSBS rules under the OBBBA (effective for stock issued after July 4, 2025):

The One Big Beautiful Bill Act significantly updated Section 1202:

• Tiered holding period: Stock issued after July 4, 2025 qualifies for a 50% exclusion at 3 years, 75% at 4 years, and 100% at 5+ years. For stock issued on or before July 4, 2025, the original 5-year requirement for full exclusion still applies.
• Increased cap: The per-taxpayer, per-issuer exclusion cap is $15 million (indexed for inflation from 2027) for stock issued after July 4, 2025, up from $10 million.
• Higher gross asset threshold: Qualifying companies may have aggregate gross assets up to $75 million at and immediately after stock issuance (up from $50 million), for post-July 4, 2025 issuances.

California does not conform to the QSBS exclusion. Gains excluded at the federal level remain fully taxable in California. See Qualified Small Business Stock (QSBS) for eligibility requirements and the California impact.

NSOs vs. ISOs: The Key Comparison

The California column is where ISOs and NSOs converge almost entirely: California taxes the spread at ISO exercise as ordinary income, just as it does for NSOs. The federal advantage of ISOs is substantially reduced for California residents because the state-level tax at exercise applies regardless of the instrument type.

The California Reality

California's tax treatment of NSOs is uncomplicated but unforgiving. The spread at exercise is ordinary income. There is no AMT calculation, no deferral, no capital gains preference at the state level. The FTB will expect state income tax at California rates on the full spread in the year of exercise.

For California residents comparing an NSO grant to an ISO grant, the federal AMT complexity of ISOs is often cited as a reason to prefer NSOs. NSO taxation is simpler: pay ordinary income tax at exercise, pay capital gains tax on subsequent appreciation. No AMT to calculate, no risk of a mismatched AMT bill if the stock declines after exercise. For contractors and advisors who are not entitled to ISO grants, this is the entire landscape.

Combined federal and California marginal rates for high earners can reach 50% or more on NSO spread income. A $200,000 spread at exercise may generate $100,000+ in combined federal and California taxes, all due in cash in the year of exercise, on shares that are illiquid and unsellable.

What to Ask When You Have NSOs

When reviewing an offer that includes NSOs, ask:

• What is the current 409A FMV per share? This tells you the spread if you exercised today.
• What is the strike price? Compare to the FMV to understand current spread.
• What is the vesting schedule? See Vesting Schedule: How Startup Equity Vesting Works.
• Does the company allow early exercise? If yes and you are joining early, early exercise at a low spread minimizes the tax bill. See Early Exercise of Stock Options.
• What is the post-termination exercise period? The window after leaving to exercise your vested NSOs. See Post-Termination Exercise Period (PTEP).
• Does the company provide sell-to-cover or other liquidity to fund exercise taxes? At later-stage private companies, some provide tender offers or facilitate secondary sales for this purpose.

For a full negotiation checklist, see Negotiating Equity Compensation at a Private Company.

This article is for educational purposes only and does not constitute tax, legal, or financial advice. NSO taxation is straightforward compared to ISOs but can result in large cash tax bills at exercise. Tax rules, including QSBS parameters, are subject to change. Always consult a qualified tax advisor before exercising options.