If your compensation package includes restricted stock units (RSUs), non-qualified stock options (NSOs), or incentive stock options (ISOs), you have probably noticed that tax season gets a lot more complicated. Each type of equity is taxed differently, at different points in time, and the rules for one can be almost the opposite of the rules for another. Getting the timing wrong can mean a surprise tax bill, a missed opportunity to lock in lower capital gains rates, or an unexpected alternative minimum tax (AMT) charge.
District Capital Management is a fee-only, fiduciary financial planning firm based in Washington, DC, founded in 2013 by Alvin Carlos, CFP®, CFA. Our team holds CFP® and CFA® credentials and works with tech professionals across the DMV area and nationwide to make sense of equity compensation as part of a broader financial plan.
This guide walks through how RSUs, NSOs, and ISOs are taxed at every stage (vesting, exercise, and sale) and compares the three side by side so you can see how your specific mix of equity affects your tax bill. If you are still deciding between an offer weighted toward RSUs and one weighted toward options, start with our RSUs vs. stock options comparison, then come back here for the tax mechanics.
How Are RSUs Taxed at Vesting?
RSUs are taxed as ordinary income on the fair market value of the shares on the day they vest, not when they are granted and not when you sell them. For most public-company employees, there is no election to defer this; the moment shares vest, the IRS treats that value as compensation, the same as a cash bonus. (A narrow exception, Section 83(i), allows a limited deferral election for qualified equity grants at certain eligible private companies, and it does not apply to typical public-company RSUs.)
At vesting, that compensation is subject to four kinds of tax:
- Federal income tax
- State income tax, if your state has one
- Social Security tax, up to the 2026 wage base of $184,500
- Medicare tax (1.45%, plus the 0.9% Additional Medicare Tax on wages above $200,000 single or $250,000 married filing jointly)
Because RSU vesting is treated as supplemental wage income, employers generally withhold federal tax at a flat 22% on the vested value, or 37% once your supplemental wages for the year exceed $1 million, a threshold that remains unchanged for 2026 under IRS Publication 15. That flat withholding rate is often lower than your actual marginal tax rate, especially for employees in the 32%, 35%, or 37% brackets, which is why many RSU recipients are underwithheld and owe additional tax at filing. Your employer will typically satisfy this withholding by selling a portion of the vested shares (“sell-to-cover”) or by holding back shares, and the vested value will appear on your W-2 as wages.
Why Does My Pay Stub Show an RSU Offset?
An RSU offset is a bookkeeping line that reconciles the value of your vested shares without adding cash to your take-home pay. When RSUs vest, you do not see a bump in your paycheck; the shares land in your brokerage account instead. But the vested value still has to be reported as wages and run through payroll for tax withholding. The “RSU offset” is how payroll adds the vested value to your taxable wages and then backs it out of your cash pay, since you received stock rather than cash. It is not a deduction or an extra tax; it is the accounting entry that lets your W-2 capture the RSU income correctly.
How Is RSU Stock Taxed When You Sell It?
Once RSUs vest, any further tax is based on capital gains, not ordinary income, measured from the price at vesting to the price at sale. The fair market value on the vest date becomes your cost basis. If you sell immediately at vest, there is typically little or no additional gain to report. If you hold the shares and they appreciate, the gain above your cost basis is a capital gain: short-term if held one year or less from vesting, long-term if held more than one year.
For 2026, long-term capital gains are taxed at 0%, 15%, or 20% depending on taxable income, with the 15% bracket applying to single filers with income up to $545,500 and married-filing-jointly filers up to $613,700. Short-term gains are taxed at ordinary income rates, which is one reason many employees choose to sell RSUs shortly after vesting rather than holding for further appreciation in a single company’s stock. For the basics of what RSUs are and how vesting schedules work, see our complete guide to RSUs.
👉 Get your free RSU Tax Calculator here. We built a free Excel RSU tax calculator that estimates your tax at vesting, flags whether your withholding is likely to fall short, and shows roughly how much you may still owe at filing. Enter your inputs to see your estimate. (It is an educational estimate, not tax advice or a guaranteed figure.)
What Are Non-Qualified Stock Options (NSOs) and How Are They Taxed?
NSOs are taxed as ordinary income on the “spread,” the difference between the exercise price and the fair market value, at the moment you exercise the option, regardless of whether you sell the shares. If your option lets you buy stock at $10 per share and it is worth $40 at exercise, that $30 spread per share is taxed as ordinary income and subject to the same 22%/37% supplemental withholding rules that apply to RSUs.
Per IRS Topic No. 427, any additional gain or loss from the exercise-date price to the eventual sale price is a capital gain or loss, taxed under the same short-term/long-term rules described above. Because the ordinary-income hit happens at exercise, exercising a large NSO grant can push you into a higher bracket and, once your wages exceed $200,000 (single) or $250,000 (married filing jointly), trigger the 0.9% Additional Medicare Tax on the amount over that threshold. The NSO spread itself is compensation income, not investment income, so it is not directly subject to the separate 3.8% Net Investment Income Tax. But pushing your modified adjusted gross income over those same $200,000/$250,000 thresholds can expose other investment income (dividends, capital gains, interest) to that 3.8% surtax for the year. For how options work mechanically before you get to the tax, see our guide to stock options.
What Are Incentive Stock Options (ISOs) and How Are They Taxed?
ISOs offer a potential tax advantage over NSOs: if you meet the holding-period requirements, the entire gain from exercise price to eventual sale price can be taxed at long-term capital gains rates instead of ordinary income rates. To qualify for this treatment, you must hold the shares for at least two years from the grant date and at least one year from the exercise date, a “qualifying disposition.” Sell before meeting both holding periods and it becomes a “disqualifying disposition,” which triggers ordinary income tax on some or all of the spread, similar to an NSO.
The catch is the alternative minimum tax. Exercising an ISO does not create regular taxable income, but the bargain element (the spread between exercise price and fair market value at exercise) is an AMT preference item. Adding that preference item to your income can raise your tentative minimum tax under the parallel AMT calculation; you only actually owe AMT for the year if that tentative minimum tax ends up higher than your regular tax liability, even though you have not sold a single share or received any cash. For 2026, the AMT exemption is $90,100 for single filers and $140,200 for married-filing-jointly filers, phasing out at a 50% rate once alternative minimum taxable income exceeds $500,000 (single) or $1,000,000 (married filing jointly).
RSUs vs. NSOs vs. ISOs: A Side-by-Side Comparison
The three types of equity compensation differ most in when tax is triggered and what rate applies.
One-line verdict: RSUs are taxed automatically at vesting, NSOs when you choose to exercise, and ISOs potentially at favorable long-term rates if you can navigate the AMT.
| Equity type | When ordinary income is triggered | Later gains | Key catch |
|---|---|---|---|
| RSUs | At vesting, on the full share value | Capital gains on appreciation after vesting | No control over timing; taxed automatically |
| NSOs | At exercise, on the spread | Capital gains on appreciation after exercise | No preferential rate on the compensation portion |
| ISOs | No regular income tax at exercise | Entire spread can be long-term gain if held 2 years from grant and 1 year from exercise | The spread is an AMT preference item at exercise |
How RSUs, NSOs, and ISOs differ on tax timing and rate. In short, RSUs are simplest because taxation is automatic and immediate; NSOs give you timing control but no preferential rate on the spread; ISOs offer the best potential outcome but only if you manage AMT and hold long enough to qualify.
AMT and ISOs: The Hidden Trap
The single most common ISO mistake we see is an employee exercising a large batch of ISOs in one calendar year without modeling the AMT impact first. Because the bargain element is added back for AMT purposes in the year of exercise, a large paper gain on stock you have not sold can generate a real tax bill if it is enough to push your tentative minimum tax above your regular tax. Exercising ISOs gradually across multiple tax years, or exercising early in the year to leave time to assess (and potentially sell some shares before December 31 if the AMT hit is too large), are both common strategies to manage this exposure.
“The biggest ISO mistakes we see aren’t about which stock to hold, they’re about triggering an AMT bill on paper gains the client never actually banked,” says Kayla Welte, CFP®, ChFC®, AFC®.
A Real-World Example (Hypothetical)
Consider Jamie, a hypothetical senior software engineer at a DC-area tech company in her early 30s with a mix of RSUs and ISOs vesting each year. (Jamie is a hypothetical client used for illustration.) Jamie’s RSUs are withheld at the flat 22% supplemental rate, but because her total income puts her in a higher marginal bracket, she consistently owes more at filing than what was withheld. Meanwhile, she has been sitting on an ISO grant for over a year without exercising, unsure whether exercising now would trigger AMT. At District Capital Management, we often help clients like Jamie build a year-by-year exercise and sale plan that accounts for AMT exposure, concentration risk in a single stock, and the broader goals in their financial plan, rather than making one-off decisions grant by grant.
Coordinating equity compensation with the rest of your investment management strategy matters just as much as understanding the tax mechanics: concentrated stock positions carry risk that a diversified plan is designed to manage.
A Common Reporting Mistake: Double-Counting Your Cost Basis
Brokerages frequently report an incorrect (too-low) cost basis for RSU and stock option sales on Form 1099-B, because they do not always account for the ordinary income you have already paid tax on at vesting or exercise. If you use the 1099-B figure without adjustment, you can end up paying tax twice on the same dollars: once as ordinary income when the shares vested or the option was exercised, and again as an inflated capital gain when you sell.
The correct cost basis for RSUs is the fair market value on the vesting date; for NSOs, it is the exercise price plus the spread already taxed as ordinary income. Your employer’s supplemental statement (not just the 1099-B) or Form 3921 for ISOs will typically show the adjustment needed on Form 8949. This is one of the most common errors we see in equity compensation tax returns, and it is worth double-checking every year you have vesting or exercise activity.
Tax Planning Strategies for Equity Compensation
Adjust your withholding. Because RSU and NSO withholding is a flat 22% (or 37% above the $1 million supplemental wage threshold) rather than your actual marginal rate, review your W-4 or make estimated tax payments to avoid an underpayment penalty.
Diversify concentrated positions. Holding a large amount of employer stock, whether from vested RSUs or exercised options, concentrates risk in a single company. Many employees sell vested RSUs promptly and reinvest into a diversified portfolio as part of a broader fee-only financial planning strategy.
Model AMT before exercising ISOs. Run the numbers before a large ISO exercise, not after. A projection that accounts for your other income, the bargain element, and the AMT exemption can tell you whether exercising this year or spreading exercises across years makes more sense.
Track your holding periods. For ISOs, mark your calendar for the two-year-from-grant and one-year-from-exercise dates. Selling even a few weeks early can convert a long-term capital gain into ordinary income.
Coordinate with your overall plan. Equity compensation decisions rarely exist in isolation; they interact with your retirement contributions and other income. A fiduciary financial advisor can help you see the full picture.
If you are trying to sort out RSUs, NSOs, or ISOs as part of a bigger financial picture, our team of financial planners in Washington, DC can help you build a plan around it.
Schedule a free discovery call to talk through your equity compensation and how it fits into your broader financial plan.
Frequently Asked Questions
RSUs are taxed as ordinary income based on the fair market value of the shares on the vesting date, with employers typically withholding at a flat 22% (37% above $1 million in annual supplemental wages). Any gain after vesting, when you eventually sell, is taxed separately as a capital gain.
Yes. The full value of your vested RSUs is reported on your W-2 as ordinary wages for the year they vest, and the taxes withheld appear there too. You may also see an “RSU offset” on your pay stub, which is the payroll entry that adds the vested value to your wages without adding cash to your paycheck.
No. RSUs are taxed at two separate events, not twice on the same dollars. You pay ordinary income tax on the share value at vesting, which becomes your cost basis, and then capital gains tax only on any appreciation between vesting and sale. Double taxation usually happens only by mistake, when a 1099-B reports a too-low cost basis (see the cost-basis section above).
NSOs are taxed as ordinary income on the spread at exercise, while ISOs generally avoid ordinary income tax at exercise but can add to the alternative minimum tax calculation on that same spread. ISOs can qualify for full long-term capital gains treatment if held two years from grant and one year from exercise; NSOs never get that treatment on the exercise-day spread.
You can reduce AMT exposure by exercising a smaller number of ISOs each year rather than all at once, and by modeling your tentative minimum tax against your regular tax liability, using the 2026 AMT exemption ($90,100 single, $140,200 married filing jointly) as part of that projection, before exercising. If a projection shows your tentative minimum tax would exceed your regular tax by a wide margin, consider spreading the exercise across years or selling some shares in the same calendar year.
Selling RSUs shortly after vesting locks in the value already taxed as ordinary income and avoids concentrating your wealth in a single company’s stock, which is why many financial planners recommend selling and diversifying rather than holding. Holding shares longer only makes sense if you have a specific reason to bet on further appreciation and can tolerate the added risk.
The exact amount depends on your marginal tax bracket, but your employer will withhold at a flat 22% federal rate on the vested value (37% above $1 million in supplemental wages for the year), which may be less than what you actually owe if you are in a higher bracket. District Capital Management helps clients project their true tax liability so there are no surprises at filing.
With NSOs, yes: exercising the option triggers ordinary income tax on the spread even if you do not sell the shares. With ISOs, exercising does not create regular income tax, but it can add to your AMT calculation on that same unsold spread, which is why AMT planning matters even before you decide to sell.
Equity compensation touches withholding, capital gains timing, AMT exposure, and portfolio concentration all at once, which is why many tech professionals work with a fee-only fiduciary advisor to coordinate these decisions. District Capital Management specializes in helping tech professionals in the DC area and nationwide integrate equity compensation into their overall financial plan.
Last updated: August 2026
Kayla Welte, AFC®, ChFC®, CFP®, has been helping clients maximize their finances since 2009. With a background in financial education & counseling, Kayla is passionate about helping people prioritize & reach their financial goals. Kayla is a Financial Planner at District Capital Management, a financial planning firm designed to help professionals in their 30s & 40s retire by 55. Schedule a free discovery call.
