NSO Tax Calculator United States

What the NSO tax calculator does

The calculator estimates the tax on non-qualified stock options (NSOs or NQSOs) from exercise to sale. NSOs are one of the most common forms of equity compensation, and they are taxed very differently from incentive stock options. The tool separates the two taxable events, so you can see where each dollar of tax comes from and how much profit you keep.

NSOs are taxed twice along the way, once as ordinary income and once as a capital gain, so the headline profit overstates what you keep. Seeing both in one estimate helps you plan your cash and timing.

How NSOs are taxed at exercise

When you exercise, the difference between the stock's fair market value on that date and your strike price is the bargain element. The IRS treats it as ordinary compensation income for that year, just like extra salary.

It is taxed at your marginal ordinary rate, often a high bracket for option holders, and, because it is compensation, it is subject to Social Security and Medicare taxes. Your employer typically withholds on the spread and reports it on your Form W-2. The calculator applies your ordinary rate and the combined employee FICA rate to show the full cost of exercising.

The stepped-up basis and the sale

After you pay ordinary income tax on the bargain element, your cost basis in the shares steps up to the fair market value on the exercise date, so the same gain is not taxed twice.

When you sell, the capital gain is the sale price minus that stepped-up basis, not minus the strike price. Shares held more than a year after exercise produce a long-term gain taxed at the lower long-term rate; shares sold within a year produce a short-term gain taxed at your ordinary rate. You choose the holding period in the calculator.

Why timing matters

The ordinary income is fixed when you exercise, whatever happens next. Only appreciation after exercise can qualify for the long-term rate, and only if you hold long enough.

A same-day (cashless) exercise and sale is simple and removes market risk, but the whole gain is taxed as ordinary income. Exercising and holding lets later appreciation be taxed at long-term rates, but it ties up cash, exposes you to a falling share price and leaves you owing tax on the original spread even if the price drops. Run both scenarios to see the size of the trade-off.

What you need to enter

• The number of options you plan to exercise.
• Your strike price per share.
• The fair market value per share on the exercise date.
• Your expected or actual sale price per share.
• Your marginal ordinary income tax rate and your long-term capital gains rate.

You enter the rates directly because they depend on your total taxable income, filing status and state. A large exercise can push part of your income into a higher bracket, so choose a marginal rate that reflects it.

Reading your result

The output shows the ordinary income and its tax, the FICA amount, the capital gain and its tax, and your after-tax profit, so you can see how much of the bill comes from compensation income and how much from the investment gain.

This is a per-lot estimate. It does not model the Social Security wage base cap, the Additional Medicare Tax, the net investment income tax, state income tax or the effect of the exercise on your overall bracket. Confirm the details with a tax professional before a large exercise.

When to use this tool

• Estimate the cash needed for tax when exercising NSOs.
• Compare a same-day sale with exercising and holding for long-term treatment.
• See how much of your equity gain is left after tax.
• Check your employer's withholding against your likely tax.

Recalculate before each new exercise, since tax rates and your circumstances change.

This is general information only and not financial advice.

About This NSO Tax Calculator

Use this NSO tax calculator to get an instant, accurate estimate. The figures follow official IRS guidance and every rate and threshold is kept up to date for 2026. Adjust the inputs above to match your situation, or browse all our calculators to plan your next step.