Taxes on equity: What you need to know?

‍Key takeaways

• Equity is taxed at three moments: vesting, exercise, and sale, not all at once.

• RSUs are taxed as ordinary income at vesting, whether or not you sell.

• NSOs tax the spread as ordinary income at exercise; ISOs defer that tax but may trigger AMT.

• The holding period determines whether a sale gain is short-term or long-term capital gain.

• ESPP and PSU tax treatment depends on holding periods and performance conditions, respectively.

• The right tax outcome depends on award type, timing, and jurisdiction, always confirm specifics with a tax advisor.

What are taxes on equity?

Equity is generally taxed at three distinct events: vesting, exercise, and sale. Each event has its own tax treatment, and not every type of equity passes through all three.

1. Vesting

Vesting is when you earn the right to your equity, the restriction period ends and the shares (or the right to them) become yours.

For restricted stock units (RSUs), vesting is the primary taxable event. There is no tax at grant. At vesting, the fair market value (FMV) of the shares is taxed as ordinary income, even if you don't sell the shares. This amount also becomes your cost basis for the shares going forward.

Stock options (NSOs, ISOs) are not taxed at vesting, vesting for options just means you're now allowed to exercise them. The tax event for options comes later, at exercise.

2. Exercise

Exercise applies only to stock options, where you pay a strike price to actually purchase the shares you've been granted the right to buy. This is where NSOs and ISOs diverge:

• Non-qualified stock options (NSOs): At exercise, the spread, the difference between the FMV of the shares and the strike price you paid, is taxed as ordinary income. This applies whether or not you sell the shares immediately.

• Incentive stock options (ISOs): At exercise, there is no ordinary income tax. However, the spread may trigger the alternative minimum tax (AMT), a parallel tax calculation designed to ensure high-income taxpayers with certain deductions or exclusions still pay a minimum amount of tax. ISOs create this AMT exposure; it's the tradeoff for their more favorable tax treatment down the line.

3. Sale

When you eventually sell the shares, tax applies to the gain, the difference between the sale price and your cost basis (what you already paid tax on, or paid out of pocket, depending on the award type).

This gain is taxed as a capital gain, and whether it's short-term (taxed at ordinary income rates) or long-term (taxed at typically lower capital gains rates) depends on how long you held the shares before selling, generally measured from vesting (for RSUs) or exercise (for options).

Types of equity awards

Different companies use different instruments at different stages. Here are few equity awards.

1. Stock options (ISOs and NSOs): The right to buy shares at a fixed strike price. Common at early and growth-stage startups.

2. Restricted stock units (RSUs): A promise to deliver shares once vesting conditions are met. Popular at later-stage private companies and public companies.

3. Employee stock purchase plans (ESPPs): Let employees buy company stock at a discount, usually through payroll deductions. Typically a public-company benefit.

4. Performance stock units (PSUs): RSUs that vest only if performance targets are hit. Common for senior roles at growth and public companies.

5. Restricted stock (RSAs): Actual shares granted upfront, subject to vesting. Often used for founders and very early employees, frequently paired with an 83(b) election.

Tax treatment of stock options

The tax treatment of stock options depends largely on the type of option, when it is exercised, and when the resulting shares are sold. Here's how the tax rules differ between ISOs and NSOs, along with the key AMT and reporting considerations.

1. ISOs vs NSOs

Both are stock options, but the IRS treats them very differently.

• ISOs (Incentive stock options): No tax at grant or vesting. At exercise, there's no ordinary income tax, but the spread may count toward AMT. Meet the holding rules (more than two years from grant and one year from exercise), and the entire gain at sale is taxed as a long-term capital gain. Miss them, and it becomes a disqualifying disposition, taxed partly as ordinary income.

• NSOs (Non-Qualified Stock Options): No tax at grant or vesting either. At exercise, the spread between strike and fair market value (FMV) is taxed as ordinary income and is subject to payroll withholding. Any further gain at sale is a capital gain.

2. AMT implications for ISOs

AMT is a separate tax calculation that can leave you owing extra tax in certain situations. When you exercise ISOs and hold the shares, the spread counts toward this calculation, reported on Form 6251.

That can create a tax bill even though you never sold anything or received cash.

Employees have a few levers to manage this exposure:

• Exercise in smaller batches across multiple years, rather than all at once, to spread out the impact and avoid a single large spike.

• Sell shares in the same year as exercise to generate cash for the tax bill, but doing so gives up the ISO's favorable tax treatment. The gain becomes ordinary income instead of a capital gain, so you're trading away the lower tax rate to avoid the AMT risk.

3. Form 3921 reporting

Employers must file Form 3921 with the IRS for each ISO exercise and provide the employee with a copy. Employee copies are typically due by January 31 of the following year; the IRS filing itself has a separate deadline (typically end of February for paper filing, or the end of March for e-filing).

Tax treatment of RSUs

RSU taxation centers on two key moments: when the shares vest and when they are eventually sold. For employers, those tax events also bring withholding and employee communication responsibilities.

1. Taxed at vesting and sale

RSUs are simpler than options in one sense: there's no strike price and no exercise decision.

At vesting, the fair market value of the shares that vest is taxed as ordinary income and reported on the employee's W-2. This happens whether or not the employee sells anything.

When the employee later sells, any gain above the vesting-date value (their cost basis) is taxed as a capital gain, short-term or long-term depending on how long they held it.

Employees can owe real tax on vested shares without having cash in hand, especially at private companies where shares can't be freely sold. Planning for that gap matters.

Tax treatment of ESPPs and PSUs

The tax treatment of ESPPs and PSUs varies by holding period, vesting conditions, and taxable events.

1. ESPP taxation

ESPPs let employees buy stock at a discount, commonly up to 15%, depending on plan design. Tax treatment hinges on how long employees hold the shares after purchase.

• Qualified disposition: Hold for more than two years from the offering date and one year from purchase, and part of the gain gets favorable long-term capital gains treatment. The discount is still taxed as ordinary income.

• Disqualified disposition: Sell earlier, and more of the gain, including the discount, is taxed as ordinary income.

2. Performance stock units and complex vesting

PSUs vest only when specific performance targets are met, like a revenue milestone or a share-price hurdle. When they vest, the FMV is taxed as ordinary income, same as RSUs.

The complication is tracking. Vesting depends on conditions that can be met partially, missed, or hit late, which makes forecasting and reporting harder than with time-based awards.

Conclusion

Taxes on equity aren't one single tax, they're a set of rules tied to specific moments in an award's life, from vesting to exercise to sale. What gets taxed, how much, and at what rate depends on which type of award you hold and how long you've held the resulting shares. The same gain can be taxed very differently for two people simply because one held ISOs while the other held NSOs, or because one sold within a year and the other waited longer.

This is why equity taxation resists simple rules of thumb, especially once cross-border grants are involved. The mechanics covered here are meant to help you ask the right questions about award type, timing, and jurisdiction before making any decision with real tax consequences. None of this replaces individual tax advice.

FAQs

1. How much do you get taxed on equity?

It depends on the equity type, the taxable event, your income bracket, holding period, and jurisdiction. Ordinary income rates apply at vesting or NSO exercise; short- or long-term capital gains apply at sale. There's no single rate. Consult a qualified tax advisor for your situation.

2. Is equity taxed when it vests or when it's sold?

Both moments can trigger a tax. RSUs are typically taxed as ordinary income at vesting, then capital gains on any appreciation at sale. Options differ: NSOs tax the spread at exercise, while ISOs may defer ordinary tax but trigger AMT.

3. When should a startup move off spreadsheets for equity taxes?

Usually around the first priced round, the first 409A valuation, or when stakeholder counts approach 20 to 50. Auditor requests and the first wave of option exercises also signal it's time for dedicated stock plan administration to reduce reconciliation errors.

4. Can you give an example of taxes on equity?

An employee exercises 1,000 NSOs at a $10 strike when FMV is $30. The $20,000 spread is taxed as ordinary income at exercise. If they later sell at $50, the additional $20,000 gain is taxed as capital gains based on holding period.

5. What happens if our 409A is stale and auditors flag our equity expense during due diligence?

A stale 409A or weak ASC 718 record can delay fundraising or trigger restatement risk. Qapita helps by keeping audit-ready 409A valuations, automated ASC 718 reporting, and Form 3921 records in one platform so your finance team can respond to auditors and investors quickly.