Equity Compensation Planning: ISOs, RSUs, and NQSOs

Equity compensation — incentive stock options, restricted stock units, nonqualified options — is how most executives build wealth that crosses the $5M threshold. It's also the most common source of unexpected six-figure tax bills. The AMT trap on ISO exercises, the 22% flat withholding gap on RSUs, and the concentrated-position problem that accumulates over vesting cycles all require deliberate planning. This guide covers the 2026 tax mechanics for each equity comp type and the strategies that matter once your total equity value is in the millions.

Equity compensation types at a glance

RSUs: the withholding gap trap

RSUs are conceptually the simplest equity comp: when your shares vest, the fair market value of the vested shares is added to your W-2 as ordinary compensation income (IRC §83). The shares become yours, and you owe income tax just as if you'd received a cash bonus.¹

The problem is withholding. Your employer is required by IRS Publication 15-T to withhold federal income tax on supplemental wages at a flat 22% for the year's first $1,000,000 of supplemental wages, and at 37% above that. For most executives with base salaries below $768,700 (the 2026 MFJ threshold for the 37% bracket), the RSU vest amount sits in the 32% or 35% bracket — but the employer withholds only 22%.²

RSU planning: sell-immediately vs. hold

At vesting, you face the same decision every time: sell the shares immediately to cover the tax bill, or hold them for future appreciation. The decision hinges on one question: would you buy this stock today at this price with cash? If the answer is no — if the only reason you're holding is that you received the shares as compensation rather than bought them — that's a concentration mistake, not a strategy.

For executives with $5M+ in accumulated equity from a single employer, the more relevant question is diversification timing. Holding 40–60% of net worth in one ticker creates a concentrated-position risk that can wipe out a decade of vesting gains in a single down quarter. The concentrated-stock diversification guide covers systematic sell-down strategies, exchange fund options, and how to time the exit to manage the capital gains bill.

ISOs: the AMT trap

Incentive stock options are the most tax-advantaged form of equity compensation — and the most dangerous if exercised without planning. The core mechanic:

• At grant: No tax event.
• At exercise (regular tax): No ordinary income recognized — you simply pay the strike price and receive shares. No W-2 entry, no withholding.
• At sale — qualifying disposition: If you hold the shares more than 2 years from the grant date AND more than 1 year from the exercise date, the entire gain (FMV at sale minus strike price) is taxed as long-term capital gain at 15–20% + 3.8% NIIT. No ordinary income ever.
• At sale — disqualifying disposition: If you sell before either holding period is met, the spread at exercise (FMV at exercise minus strike price) is immediately reclassified as ordinary income in the year of sale.

The apparent advantage: convert potentially $500,000–$5,000,000 of gain from 37% ordinary income rates to 23.8% LTCG rates, saving $65,000–$650,000 in federal taxes. The catch: the AMT.

Why ISOs trigger AMT

Under the Alternative Minimum Tax (AMT), the spread on ISO exercise — the difference between FMV and strike price at the moment you exercise — is a preference item that gets added back into your AMT Income (AMTI). Regular tax says no income was recognized; AMT says the full spread is income.³

For a 2026 MFJ household:

• AMT exemption: $140,200 — reduced by $0.50 for every dollar of AMTI above $1,000,000⁴
• AMT rate: 26% on the first $232,600 of taxable AMTI, 28% above that
• AMT owed: The excess of the tentative minimum tax over your regular tax liability

The OBBBA (July 2025) moved the phaseout trigger to $1,000,000 of AMTI for married filers (single: $500,000) and raised the phaseout rate to 50% — meaning the effective marginal AMT rate during the phaseout range is ~42% (28% × 1.5). Once AMTI exceeds $1,280,400 (MFJ), the exemption is fully phased out and AMT applies directly.

If the stock subsequently drops in value, you may have paid $242,000 in AMT on gains you never realized. This scenario — called the "AMT death spiral" — destroyed significant wealth for employees of companies that collapsed in 2000–2001 and again in 2008–2009.

AMT credit carryforward

AMT paid on ISO exercises is not entirely lost. It generates a Minimum Tax Credit (Form 8801) that can offset future regular tax liability in years when your regular tax exceeds your tentative minimum tax. For many executives, this credit is recovered over 3–7 years following a large ISO exercise year. But the timing mismatch — pay AMT now, recover credit over years — is a real cash-flow risk.

ISO AMT Calculator

Estimate your AMT exposure before exercising incentive stock options:

ISO planning strategies

The goal is to exercise ISOs in years and tranches that minimize AMT, while maximizing the period available to meet qualifying-disposition holding periods.

• Exercise in low-income years. Sabbaticals, leaves of absence, early retirement — years when W-2 income is low create more "AMT headroom" before the tentative minimum tax exceeds regular tax. Each $140,200 of AMT exemption (MFJ) allows roughly $140,000 in spread before AMT kicks in at lower ordinary income levels.
• Spread exercises across years. Exercising 10,000 shares at an $80 spread in one year may generate $250,000 in AMT. Exercising 3,300 shares/year over three years at the same spread may generate zero AMT each year if spread stays within the AMT exemption.
• Model the qualifying-disposition math before exercising. If you exercise ISOs and the stock needs to hit a specific price to offset the AMT cost through preferential LTCG treatment, know that break-even before you exercise — especially for pre-IPO or volatile stocks.
• Coordinate with a Roth conversion. In high AMT years, your regular tax is lower relative to income. This sometimes creates an opportunity to do additional Roth conversions within the year — you're already partially sheltering income under AMT rules.
• QSBS overlap. If your ISOs are in a qualified small business (gross assets under $75M, C-corp), the shares may qualify for the Section 1202 QSBS exclusion — eliminating up to $15M of federal gain entirely. This interacts with ISO qualifying-disposition math in important ways; consult a tax attorney early.

NQSOs: simpler, no AMT, higher ordinary income rate

Nonqualified stock options (NQSOs) are taxed more straightforwardly than ISOs — but at a higher rate. When you exercise NQSOs:

• Spread at exercise = ordinary income. The difference between FMV and strike price is added to your W-2 and taxed at your marginal ordinary income rate (up to 37% federal + 3.8% NIIT if applicable).⁵ Your employer withholds at exercise — typically at the 22% flat supplemental rate, creating the same withholding gap as RSUs.
• Cost basis resets to FMV at exercise. Your holding period for capital gains purposes starts on the exercise date.
• Post-exercise appreciation = LTCG. If you hold for more than 12 months after exercise, subsequent appreciation is taxed as long-term capital gains (20% + 3.8% NIIT at HNW income levels). Under 12 months: short-term capital gains at ordinary rates.

For executives with a mix of ISOs and NQSOs in the same company, NQSOs are typically exercised first (to use up the ordinary income "bucket" from the spread at a rate you'd pay anyway) and ISOs last (preserving the LTCG advantage for the largest share blocks).

ESPPs: the underutilized benefit

Employee Stock Purchase Plans allow employees to purchase employer stock at a discount — typically 15% off the lower of the beginning or end of a 6-month or 2-year offering period. A qualifying Section 423 ESPP with a 2-year lookback provision at a strong-performing company can generate significant after-tax value.

Tax treatment for qualifying dispositions (held 2+ years from offering date AND 1+ year from purchase date):

• The statutory discount (up to 15% of offering-date price) is taxed as ordinary income in the year of sale.
• Everything above the discount is LTCG if the shares appreciated.

For most HNW executives, ESPP participation capacity (contribution limits vary by plan, typically 10–15% of pay, subject to $25,000 IRS cap on discount value per year) is modest compared to ISO or RSU grants. But the guaranteed 15% discount, compounded across a 2-year holding period at qualifying-disposition rates, represents a high-return, low-risk position worth maximizing.

The concentrated-position problem

Over a 10-year vesting cycle, an executive at a $5B+ company can accumulate $5M–$20M of concentrated employer stock — even after regular sales. Each RSU vest adds new shares; exercised ISOs create more. The position isn't just a concentration risk; it also creates a compounding embedded-gain problem: the larger the unrealized gain relative to basis, the more painful any sell-down.

Strategies for managing the accumulated concentrated position:

• Exchange funds (IRC §721): Contribute shares to a partnership alongside other investors contributing different concentrated positions. You diversify without a taxable sale — but you must hold for 7 years, and the fund must hold ≥20% in non-publicly-traded assets. Suitable for positions with very large embedded gains.
• Charitable Remainder Unitrust (CRUT): Donate appreciated shares to a CRUT; the trust sells without capital gains tax. You receive an income stream for a term of years plus a charitable deduction. Best for executives with philanthropic intent — a forced choice between charitable and investment objectives.
• Gradual sell-down with direct indexing offsets: Systematic annual sales paired with harvested losses from a direct-indexing portfolio in a taxable account. The losses offset the gains from the concentrated-stock sales, reducing the net capital gains tax. See the Direct Indexing TLH Calculator for the math.
• DAF for appreciated shares: Donating highly appreciated employer stock directly to a Donor-Advised Fund eliminates the embedded capital gain entirely and generates a full fair-market-value deduction. Particularly effective in a high-income year — a large RSU vest year, for example.

See the full Concentrated Stock Diversification guide for strategy selection criteria, worked examples, and a decision matrix by position size and charitable intent.

How an HNW financial advisor coordinates equity comp planning

Equity compensation planning is multidimensional: it touches federal income tax, AMT, NIIT, state income tax, capital gains planning, estate planning (ISOs don't step up in basis at death), and concentrated-position risk. A generalist wirehouse advisor typically manages the investment portfolio and leaves the option exercise decisions to you.

HNW-focused fee-only advisors who specialize in executive compensation typically:

• Build a multi-year exercise model showing AMT exposure at different exercise paces
• Coordinate with your CPA on timing (what year, what tranche size, what order: ISOs vs. NQSOs)
• Manage the concentrated-position diversification strategy across tax years
• Integrate equity comp vesting and exercise events with Roth conversion windows and retirement cash-flow projections
• Flag QSBS eligibility for founders and early employees before the company grows past the $75M gross asset threshold

The difference at $5M+ in equity is usually not which option-pricing formula to use — it's whether the advisor noticed that your $800,000 ISO exercise in December would push you into an AMT phaseout range that costs $140,000 in additional tax versus waiting until January of a lower-income year. That kind of coordination requires an advisor who understands the interaction between all the moving parts, not just the investment portfolio.