RSU vs Stock Options: Which Is Worth More?

RSUs and stock options both appear in offer letters as "equity," but they are fundamentally different instruments. RSUs deliver shares automatically at vesting — they have value as long as the stock is worth anything. Options give you the right to buy shares at a fixed price and are worthless if the stock never rises above that price. The better choice depends on the company's current valuation, its growth trajectory, and how much risk you are willing to accept in your compensation package.

RSU vs stock options: which is worth more

RSUs guarantee value at vesting because you receive shares outright — if the stock is at $30 when 100 shares vest, you have $3,000 in income, taxed as wages. Options only pay off if the stock rises above the strike price. If you have options to buy 1,000 shares at $30 and the stock is still at $30 at expiration, those options are worth zero.

How RSUs work at vesting

RSUs have two conditions that must be met before shares are delivered: a time condition (vesting schedule) and sometimes a performance condition. Most tech companies use a 4-year vest with a 1-year cliff — meaning no shares vest for the first 12 months, then 25% vests on the one-year anniversary, and the remaining 75% vests monthly or quarterly over the following 36 months.

When shares vest, the fair market value on that date is added to your W-2 as ordinary income — taxed at your marginal rate plus FICA. Your employer typically withholds taxes using a sell-to-cover mechanism: a portion of your vesting shares is automatically sold to cover estimated taxes. The default federal withholding rate is 22% (supplemental wage rate), which is frequently insufficient for employees in the 32–37% bracket.

For a complete breakdown of RSU tax mechanics, vesting schedules, and the hold-vs-sell decision, see RSU taxes: how stock vesting works and what you owe.

How stock options work: ISOs vs NSOs

A stock option grants the right — not the obligation — to purchase a specific number of shares at a fixed price (the strike price or grant price) within a defined window (typically 10 years from grant, 90 days after leaving the company). If the stock never rises above the strike price, the options expire worthless.

ISOs (Incentive Stock Options) are granted only to employees and receive preferential tax treatment: no ordinary income tax at exercise. The gain is typically taxed at long-term capital gains rates if you hold the shares for at least 2 years from grant and 1 year from exercise. The risk: exercising ISOs triggers Alternative Minimum Tax (AMT) on the spread at exercise, which can create a large tax bill even if you never sell the shares.

NSOs (Non-Qualified Stock Options) can be granted to employees, contractors, and board members. At exercise, the spread between the strike price and the market price is taxed as ordinary income (just like salary) and reported on your W-2 or 1099. Any additional appreciation after exercise is taxed as capital gains — long-term if held more than 12 months.

Worked example: 1,000 RSUs vs 4,000 NSOs at four outcomes

Company current valuation: $20/share (409A). Strike price for options: $20. Vesting: 1,000 RSUs or 4,000 NSOs over 4 years. Assuming 32% federal marginal rate.

The pattern is clear: in downside or flat scenarios, RSUs win decisively. In high-growth scenarios (4× or greater), options win by a wide margin because you hold a larger number of units with leveraged upside. The inflection point is at roughly 2× growth, where the after-tax outcome is comparable. This is why early-stage startup options can be transformative — and why RSUs are standard at established companies where flat-to-moderate growth is more likely.

ISO tax strategy: exercise timing and AMT exposure

ISOs held long enough can be taxed at long-term capital gains rates (0–20%) rather than ordinary income rates (22–37%). But the holding period requirement creates a catch: you must hold ISO shares for at least 1 year after exercise and 2 years after the original grant date to qualify. During that holding period, the spread at exercise is an AMT preference item — it counts toward AMT income and may trigger AMT liability even with no cash proceeds.

The early-exercise strategy works for ISOs at very early-stage companies: if the current 409A valuation is low (say, $0.10/share), you can exercise ISOs immediately after grant for a trivial cash outlay, start the LTCG clock, and avoid AMT because the spread at exercise is nearly zero. If the company grows 10× before exit, the entire gain qualifies for LTCG rates (potentially 0% if income is low enough at exit).

This is also a significant consideration when negotiating your package — see the guide to how to negotiate a salary offer for frameworks that apply to equity negotiation.

Which to choose when you have a preference

Choose RSUs if:

• The company is public or late-stage pre-IPO with a known, established value.
• You want guaranteed compensation that does not expire or require a cash outlay to capture.
• You prefer simplicity — no exercise decision, no AMT calculation, no cash required.
• Company growth is expected to be moderate (under 2× over the vesting period).

Choose options (especially ISOs) if:

• The company is early-stage with a low current 409A valuation and a clear path to 5–10× growth.
• You can afford to exercise early at the current 409A price (start the LTCG clock).
• You have strong conviction in the company's trajectory and are prepared for the options to potentially expire worthless.
• The option count is high relative to total shares outstanding — understand the cap table before valuing options.

Always ask for the current 409A valuation, the total shares outstanding, the most recent preferred share price (from the last funding round), and the strike price before accepting any options offer. A $50,000 options grant at a $5 strike price in a company with 100 million shares outstanding on a $500M post-money valuation is a very different offer than the same grant at a $0.10 strike price in a company at $5M valuation. For a comparison of total compensation value across employment types, see employee vs contractor: the true cost employers actually pay.

Authoritative sources

• IRS Tax Topic 427 — Stock Options — Official IRS guidance on ISO and NSO tax treatment, holding period requirements, and AMT implications.
• IRS Publication 525 — Taxable and Nontaxable Income — Covers employee stock options and restricted stock in detail, including elections and form filing requirements.
• SEC — Employee Stock Option Plans — Investor education on how stock option plans work, vesting schedules, and the difference between ISOs and NSOs.

Key takeaways

• RSUs have guaranteed value as long as the stock is worth anything — options expire worthless if the stock never rises above the strike price. RSUs are lower risk; options offer higher leverage on upside growth.
• RSUs create ordinary income at vesting; NSOs create ordinary income at exercise — in both cases, you owe income tax regardless of whether you sell the shares, at the marginal rate that applies to your total income that year.
• ISOs can be taxed at long-term capital gains rates if holding periods are met (2 years from grant, 1 year from exercise), but exercising ISOs triggers AMT on the spread — run the AMT calculation before exercising large ISO grants.
• The "1,000 RSUs vs 4,000 options" comparison is meaningless without the 409A — the number of shares means nothing without knowing the strike price, current valuation, total shares outstanding, and the company's liquidation preferences.
• At flat or modest growth (under 2×), RSUs win; at high growth (4× or more), options win by a large margin. The implied growth bet is the core decision: RSUs win in established companies, options win in early-stage high-growth scenarios.
• The default 22% supplemental wage withholding on RSU vests is often insufficient for employees in the 32–37% bracket — adjust your W-4 or make quarterly estimated payments after each vest event to avoid a large April bill.

Frequently asked questions

What is the difference between RSUs and stock options in simple terms?

RSUs give you actual shares on a schedule — guaranteed, no purchase required. Stock options give you the right to buy shares at a locked-in price. If the stock rises above that price, the options are valuable; if not, they expire worthless. RSUs are simpler and lower risk. Options are higher risk with higher potential reward in high-growth companies.

Do RSUs or stock options pay more at an IPO?

It depends on the IPO price relative to the grant price. At 2× growth, the after-tax outcomes are roughly comparable. At 5–10× growth, options significantly outperform RSUs on a per-grant-value basis because options are leveraged on the upside — you only pay the original strike price for shares worth far more. RSUs win if the company's value stays flat or declines from when the grant was issued.

Can I hold RSU shares after vesting to avoid taxes?

Holding RSU shares does not defer the ordinary income tax — it was owed at vesting regardless. Holding after vesting starts the capital gains clock: sell within 12 months of vest and any additional gain is short-term (ordinary rate); hold beyond 12 months and any additional gain is long-term (0–20%). Holding RSUs concentrates your compensation in a single stock; most financial advisers recommend selling and diversifying unless you have strong conviction in continued appreciation.

What is a 409A valuation and why does it matter for options?

A 409A is an independent appraisal of the fair market value of a private company's common stock, required by the IRS under Section 409A. Your option strike price must be set at or above the most recent 409A valuation. If a startup last valued its common stock at $1.00/share but just raised a Series B valuing preferred shares at $10.00/share, your strike price is $1.00 but the implied common value may be significantly higher — making those options immediately valuable in theory.

What happens to RSUs and options when I leave a company?

RSUs: unvested RSUs are forfeited when you leave. Vested RSUs are already yours — you own the shares. Options: unvested options are typically forfeited. Vested options can usually be exercised within 90 days of departure (for ISOs, after that window they convert to NSOs). Leaving shortly before a large vest date means forfeiting unvested shares — a concept sometimes called the "golden handcuff." Check your option agreement for post-termination exercise periods, as some companies offer extended windows of 1–10 years.