Employee stock options: ISOs vs. NSOs and how each is taxed
This article was produced with AI assistance.
Employee stock options are contracts that give you the right to buy company stock at a set price [1]. The two main types are Incentive Stock Options (ISOs) and Non-Qualified Stock Options (NSOs), and they are taxed differently under federal law [2, 3]. NSOs trigger ordinary income tax when you buy the shares, which is called exercising the option [2]. ISOs do not trigger ordinary income tax at exercise, but they can trigger the Alternative Minimum Tax (AMT) [3].
An option contract specifies a set price, known as the exercise price or strike price, at which you can buy the stock [1]. When you exercise the option, you buy the shares at that exercise price [2]. The difference between the fair market value of the stock when you exercise and your exercise price is called the spread [2].
Non-Qualified Stock Options (NSOs)
When you receive an NSO, you generally do not owe tax [2]. However, you must pay ordinary income tax on the spread when you exercise the option [2]. Your employer will report this spread as taxable wages on your Form W-2 [2].
When you eventually sell the stock, you will have a capital gain or loss [2]. This gain or loss is the difference between the sale price and your tax basis, which is the fair market value of the stock on the day you exercised the option [2].
Incentive Stock Options (ISOs)
ISOs are statutory stock options that qualify for special tax treatment [3]. You do not owe ordinary income tax when you receive or exercise an ISO [3].
Instead, you may owe AMT in the year you exercise your ISO [3]. To calculate your AMT, you must include the spread at exercise as an adjustment to your income [3].
To qualify for capital gains tax treatment on your ISO, you must hold the stock for more than two years from the date your company granted you the option, and for more than one year from the date you exercised the option [3].
If you meet this holding period, any gain you make when you sell the stock is taxed as a capital gain [3]. If you sell the shares before meeting this timeline, it is a disqualifying disposition [3]. In a disqualifying disposition, you must report the spread at exercise as ordinary income, and any remaining profit is taxed as a capital gain [3].
Next Step for the Reader
Check your employer's stock option plan agreement to identify whether your options are ISOs or NSOs, then write down your grant dates and exercise prices to estimate your potential tax liability.