VIP Financial Insights | Expert Wealth & Tax Strategies for High Earners

Tax Season 2026: Reporting RSUs, ISOs, ESPPs, and Stock Compensation

Written by Mark Stancato, CFP®, EA, ECA, CRPS® | Jan 23, 2026 3:44:03 PM

Equity compensation reporting requires precise coordination across payroll, brokerage, and tax systems.

Key Takeaways

  • Equity compensation is taxed across multiple systems and timeframes, not once.
  • Most IRS notices stem from cost basis and timing mismatches, not aggressive behavior.
  • Form 8949 is where most equity reporting errors either get fixed or locked in.
  • AMT exposure and credits remain a major blind spot for ISO holders.
  • State tax allocation has become a growing source of risk for remote workers.

Updated for filing season as April 15th, 2026, approaches

Tax season has a way of exposing uncomfortable truths. One of them is this: equity compensation does not behave like normal income, yet it is often reported as if it does. The result is confusion, overpayment, IRS notices, and a lingering sense that something went wrong even when the return was "filed correctly."

For employees, executives, founders, and early-stage company veterans who earned income from stock compensation or company shares in 2025, this filing season demands extra care. Reporting rules are fragmented across forms, timing mismatches are common, and the IRS has become far more aggressive in matching payroll data to brokerage reporting.

This article walks through what actually matters for Tax Season 2026. Not the surface-level explanations, but the mechanics, the traps, and the planning implications that show up when stock compensation meets a real tax return.

Why Stock Compensation Reporting Still Trips Up High Earners

Equity compensation is not taxed once. It is taxed in stages, under different systems, often years apart.

Payroll reports income when compensation vests or options are exercised. Brokerages report proceeds when shares are sold. The IRS receives both streams of information independently, then attempts to reconcile them. What the IRS does not receive is your full tax basis story, your AMT adjustments, or the economic reality of how those shares were acquired.

That burden falls on you.

Why 2026 Is Less Forgiving
  • Broker reporting has become more standardized, but not more accurate.
  • IRS matching algorithms are faster and more confident.
  • Equity compensation usage has expanded beyond traditional tech hubs.
  • Remote work continues to complicate state tax sourcing.

Filing errors are no longer rare. They are routine.

The Forms That Actually Matter for Stock Compensation

If your tax return includes equity compensation, your story is told across multiple forms. Each one captures a fragment, never the whole picture.

Core Federal Forms

  • Form 1040: The anchor document, but rarely the problem
  • Schedule 1: Additional income that may include stock-related adjustments
  • Schedule D: Capital gains and losses summary
  • Form 8949: Where stock compensation errors are either corrected or cemented
  • Form 6251: Alternative Minimum Tax calculations, especially for ISOs
  • Schedule 2: Additional taxes, including AMT
  • Schedule 3: Credits, including AMT credit carryforwards

Most reporting mistakes originate on Form 8949 and quietly cascade from there.

RSUs: Simple in Theory, Dangerous in Practice

Restricted Stock Units remain the most common form of equity compensation and the most commonly misreported.

How RSUs Are Taxed

  • RSUs are taxed as ordinary income when they vest
  • That income is included on your Form W-2
  • Shares are typically sold later, creating a capital gain or loss

So far, straightforward.

The Double-Tax Trap

The problem emerges at the sale. Brokerage Form 1099-B often reports proceeds correctly but understates or omits cost basis. If you fail to adjust the cost basis on Form 8949, you may pay tax twice on the same income: once as wages and again as capital gain. IRS instructions for Form 8949

Even in 2026, this remains one of the most frequent causes of IRS CP2000 notices.

"Covered security" status does not guarantee correct basis reporting. It only guarantees that something was reported.

Stock Options: One Term, Two Very Different Tax Regimes

Nonqualified Stock Options (NSOs)

NSOs generate ordinary income at exercise equal to the spread between the exercise price and fair market value.

  • Income appears on your W-2
  • Cost basis equals strike price plus recognized income
  • A sale creates capital gain or loss

Timing mismatches are common. Many taxpayers exercise in one year and sell in another, creating reporting gaps that require careful reconciliation.

Incentive Stock Options (ISOs)

ISOs remain the most misunderstood equity instrument in the tax code.

At exercise:

  • No regular tax is triggered.
  • AMT income is created based on the spread.

At sale:

  • Qualifying dispositions receive favorable tax treatment.
  • Disqualifying dispositions trigger ordinary income.

Meanwhile, AMT basis and regular tax basis diverge and must be reconciled. Form 6251 errors are widespread, particularly when AMT credits are involved.

In volatile markets, AMT exposure has increased, not decreased. Many taxpayers now hold AMT credits they do not realize they can recover.

ESPPs: The Friendly Plan With Hidden Math

Employee Stock Purchase Plans appear simple but conceal complex tax treatment.

Key ESPP Concepts

  • Qualified vs nonqualified plans
  • Discount treatment at purchase
  • Ordinary income recognition at sale
  • Capital gain for the remaining appreciation

Brokerages almost never calculate ESPP tax correctly. Form 3922 is informational, not authoritative. Taxpayers must reconstruct the transaction manually.

Small errors here rarely trigger immediate notices. Instead, they quietly accumulate across years.

Company Shares Outside Brokerage Accounts

Not all equity arrives via a trading platform.

This category includes:

  • Founder shares
  • Early exercise shares
  • Private company stock
  • Restricted shares subject to 83(b) elections

Common 2026 issues include missing basis records, forgotten elections, and unsupported QSBS eligibility assumptions.

April is the worst month to discover that your equity history lives in old email threads.

State Tax Complications Are Getting Louder

Multi-state equity income sourcing remains one of the fastest-growing areas of tax controversy.

  • Allocation of RSUs across work locations
  • Option income sourcing over vesting periods
  • Remote work nexus exposure
  • Increased enforcement by California, New York, and Massachusetts

The IRS may be the referee, but states are increasingly aggressive participants.

Common 2026 Filing Errors the IRS Is Actively Flagging

Patterns emerging this filing season include:

  • Unadjusted 1099-B proceeds
  • AMT income reported without AMT basis tracking
  • RSU income double-counted
  • ESPP discounts mischaracterized
  • Holding periods are incorrectly classified

CP2000 notices are not audits, but they are not harmless. Most stem from preventable reconciliation failures.

What To Do Before April 15, 2026

A disciplined approach matters more than speed.

  • Reconcile W-2 income to equity events
  • Review every Form 1099-B line by line
  • Adjust Form 8949 deliberately
  • Track AMT credits and carryforwards
  • Preserve equity documentation

Compliance looks backward. Planning looks forward. Tax season punishes those who confuse the two.

The VIP Perspective

Stock compensation is not just income. It is a system spanning payroll, brokerage reporting, tax law, and long-term wealth planning.

Most professionals see only part of it. At VIP Wealth Advisors, equity compensation is treated as a lifecycle decision rather than a line item.

When no one owns the whole map, the system breaks. When it is integrated properly, stock compensation becomes what it was meant to be: a wealth-building tool, not a recurring tax surprise.

Stock Compensation Tax Reporting FAQs

+ How are RSUs taxed in 2026?

RSUs are taxed as ordinary income when they vest. The value at vesting is included on Form W-2. Any subsequent sale creates a capital gain or loss that must be reported separately.

+ Why does my 1099-B show the wrong cost basis for RSUs?

Brokerages often exclude the income already reported on your W-2 from the cost basis. Taxpayers must adjust the basis on Form 8949 to avoid double taxation.

+ Do I owe tax when I exercise incentive stock options?

You do not owe regular tax on exercise, but you may owe Alternative Minimum Tax. The spread at exercise, called bargain element, is included in AMT income and reported on Form 6251.

+ What is the most common mistake with ISOs?

Failing to track separate AMT and regular tax bases. This leads to incorrect gain calculations and missed AMT credits.

+ How are ESPP discounts taxed?

Part of the discount is taxed as ordinary income at the time of sale. The remaining gain may qualify for capital gain treatment, depending on the holding period.

+ Do I need to report stock compensation even if I didn’t sell shares?

Yes. RSU vesting and option exercises can create taxable income even if no shares are sold.

+ How does remote work affect stock compensation taxes?

Equity income may need to be allocated across states based on where services were performed during vesting periods.

+ Can mistakes in stock compensation reporting trigger IRS notices?

Yes. Most CP2000 notices related to equity compensation arise from basis mismatches and timing errors, not intentional misreporting.

Have Equity Compensation and Want It Done Right?

If stock compensation plays a meaningful role in your income or net worth, tax filing should not be reactive. It should be integrated with planning.