RSU vs Stock Options: Which Should You Choose When Comparing Offers?

RSUs are shares granted at no cost that become yours as they vest; stock options only give you the right to buy shares later at a fixed strike price. RSUs are generally safer because they hold value unless the stock goes to zero, while options can expire worthless and still cost you cash to exercise. Which one is "better" depends on the company's stage, your risk tolerance, and the tax bill each one triggers.

What's the Difference Between RSUs and Stock Options?

An RSU is a promise of actual shares, delivered once a vesting condition is met. A stock option is only a chance to buy shares later at a price fixed today, called the strike price.

RSUs: Shares With No Cost to You

When an RSU vests, you own the shares outright at no cost. If the stock is worth $50 a share and 100 units vest, you now have $5,000 in stock, before taxes — no purchase decision, no cash outlay.

Stock Options: The Right to Buy at a Set Price

A stock option gives you no shares until you exercise it, which means paying the strike price out of pocket. With a $10 strike and the stock trading at $40, exercising 1,000 options costs $10,000 up front, regardless of what the shares eventually sell for. If the stock falls below your strike price, the options are "underwater" and worth nothing — see our guide to stock option strike prices for how that number is set.

A grant of "10,000 shares" sounds similar whether it's RSUs or options, but the two aren't equivalent. RSUs have a floor value above zero as long as the stock has any price at all; options have a floor of zero and only gain value above your strike price. Comparing two offers by share count alone, without accounting for which type of equity each one uses, is comparing two different instruments as if they were the same thing.

How Are RSUs Taxed?

RSUs are taxed as ordinary income at vesting, based on the stock's value that day, whether or not you sell any shares.

Tax at Vesting, Not at Grant

You owe no tax when RSUs are granted, only when they vest. At vesting, the full market value of the shares is added to your W-2 wages for that year. Most employers withhold shares automatically to cover this ("sell-to-cover" or "net settlement"), so you typically receive fewer shares than you were granted.

Default Withholding Often Falls Short

Employers generally withhold at the IRS supplemental wage rate: 22% on the first $1 million of supplemental wages in a calendar year from that employer, and 37% above that, according to Monument Wealth Management's breakdown of RSU taxation. That 22% rate is often lower than your actual marginal rate once you're in the 24% bracket or higher, which means a surprise balance due at filing is common for RSU holders who don't adjust their withholding elsewhere. Once vested, any further price movement is a capital gain or loss when you sell: hold the shares more than a year past vesting and the gain qualifies for long-term rates; sell sooner and it's taxed as a short-term gain at ordinary rates.

How Are Stock Options Taxed?

Stock option taxation depends heavily on whether you hold incentive stock options (ISOs) or non-qualified stock options (NSOs) — a distinction we cover in depth in ISO vs NSO: What's the Difference.

NSOs: Ordinary Income at Exercise

Exercising an NSO triggers ordinary income tax on the "spread" — the gap between the market price and your strike price — even if you don't sell. Exercise 1,000 options with a $10 strike when the stock is at $40, and you owe tax on $30,000 of compensation income right then, per Carta's guide to stock option taxation. That income is also generally subject to payroll tax withholding, so you may need cash beyond the exercise cost itself.

ISOs: The AMT Trap and the Qualifying-Disposition Payoff

ISOs don't trigger ordinary income tax at exercise, but the spread can count toward the alternative minimum tax (AMT) — the single most common surprise tax bill in startup equity. We cover the mechanics in AMT on ISO Exercise.

The Holding Period That Unlocks Long-Term Capital Gains

To get the best tax treatment on an ISO (a "qualifying disposition"), you must hold the shares at least two years from the grant date and at least one year from the exercise date, per mystockoptions.com's explanation of ISO holding period requirements. Sell before either deadline and it becomes a "disqualifying disposition," where the exercise spread is taxed as ordinary income instead.

Risk, Cost, and Company Stage

RSUs Have Value Unless the Stock Goes to Zero

Because RSUs are shares rather than a right to buy shares, their downside is limited to the stock price itself. A declining stock still has some value; it doesn't erase your grant the way a falling price can erase an option's value entirely.

Options Can Expire Worthless — and Still Cost You Cash to Exercise

Options carry more risk in both directions. If the stock never rises above your strike price, the options are worthless and you've lost nothing extra, but you also never had anything to show for the grant. If you do exercise, you've spent real cash before knowing whether the shares will ever be worth more than you paid. That's also why earlier-stage, higher-growth companies tend to grant options: the low strike price offers outsized upside if the company succeeds, and the stock typically has no liquid market anyway. Later-stage and public companies tend to shift toward RSUs instead, since the stock is less volatile and employees generally prefer the simpler, lower-risk instrument once shares can actually be sold on a public market.

How to Compare an RSU Offer to an Options Offer

Convert Both to a Number You Can Actually Compare

Don't compare share counts directly. For options, subtract the exercise cost and your best estimate of exercise-time taxes from the projected future value; for RSUs, apply your marginal tax rate to the projected vesting-date value. That post-tax, post-cost number is what's actually comparable across offer types — a large options grant can look more generous on paper than a smaller RSU grant until you run this math and account for AMT exposure on ISOs. Ask for the current 409(a) valuation or strike price so you can estimate this before you negotiate.

Weigh Vesting Schedule and Strike Price Alongside the Headline Grant

The vesting schedule matters as much as the grant size. Check whether either offer has a vesting cliff, and whether a double-trigger acceleration clause protects your equity in an acquisition. Two offers with identical headline numbers can differ substantially once you factor in these terms.

Questions to Ask Before You Accept

Questions About the Equity Itself

Ask how many shares or options you're being granted, the strike price (for options) or most recent valuation (for RSUs at a private company), and the full vesting schedule including any cliff.

Questions About Exercise Windows and Liquidity

If you're granted options, ask how long you'll have to exercise them after leaving — often a short window, covered in our 90-day exercise window breakdown — and whether the company offers any way to sell shares before an IPO.

Key Takeaways

• RSUs are shares granted at no cost and taxed as ordinary income when they vest; stock options require paying a strike price to exercise and carry more complex, two-stage tax treatment.
• RSUs hold value unless the stock goes to zero; options can expire worthless and still require cash up front to exercise.
• ISOs require holding shares two years from grant and one year from exercise to get favorable capital gains treatment, and can trigger AMT at exercise.
• Compare offers by post-tax, post-cost value, not by raw share count, factoring in vesting schedules and acceleration clauses alongside the headline grant.

Frequently Asked Questions

Can an offer include both RSUs and stock options?

Yes. Companies transitioning from private to public often grant a mix of both, or shift new hires from options to RSUs as the stock becomes more liquid. Read your offer letter's equity section carefully to confirm which instrument, or combination, you're actually being granted.

Are RSUs always better than stock options?

Not necessarily. RSUs are lower-risk, but options offer more upside at an early-stage company that grows substantially, since a low strike price locks in cheap future ownership. It depends on your risk tolerance and conviction in the company.

Do I owe taxes on stock options I haven't sold?

For NSOs, yes — the spread at exercise is taxed as ordinary income even if you hold the shares. For ISOs, exercising doesn't trigger ordinary income tax, but the spread may still count toward AMT, which can create a tax bill without a sale.

How do I value RSUs or options at a private company?

RSUs are valued using the company's most recent 409(a) valuation or a recent funding round price; options are that same valuation minus your strike price. Both are estimates until the company goes public or is acquired, since there's no public market setting the price day to day.

Equity grants are hard to compare side by side precisely because RSUs and options behave so differently once tax and risk enter the picture. Taxation also depends on your specific plan documents, state, and income level, so treat the figures above as general information, not individualized tax or legal advice — talk to a tax professional before making exercise or sale decisions. If you want help reading the equity section of an offer letter alongside everything else in it, Offer XRay can walk through your document and flag what's missing. For a broader framework on weighing two offers against each other, see how to compare two job offers.