What Does W-2 Box 12 Code V Mean on Your Taxes?

Code V in Box 12 of your W-2 is the amount of ordinary income you recognized when you exercised non-statutory stock options during the year. It represents the spread between what you paid for the shares and what they were worth on the day you exercised, and your employer has already included that amount in your Box 1 wages. You don’t add it to anything on your return. The reason Code V exists is so you (and the IRS) can tell later how much of your wages came from an NSO exercise, which matters when you eventually sell the stock.

What the Code V Number Represents

When you exercise a non-statutory stock option, you buy company stock at a preset exercise price that’s lower than the stock’s current market value. The difference is your spread, and the IRS treats it as ordinary compensation, no different from salary. Your employer calculates the spread on the exercise date and reports it in Box 12 with the letter V.¹

The legal basis is Section 83 of the Internal Revenue Code, which says that when you receive property for performing services, the excess of its fair market value over what you paid counts as gross income.² For NSOs, that taxable moment lands on the exercise date, because that’s when you actually receive stock with a determinable value.

A Short Example

Say your employer granted you options with a $10 exercise price. On the day you exercise, the stock trades at $50. The spread is $40 per share. If you exercise 500 options, your Code V amount is $20,000. That $20,000 appears in Box 12 next to the letter V, and the same $20,000 is already folded into Box 1.

Where the Same Amount Shows Up on Your W-2

Your employer is required to include the Code V amount in three other places on the form:¹

Box 1 (wages, tips, other compensation) — your total federal taxable wages, including the NSO spread.
Box 3 (Social Security wages) — subject to the Social Security wage base of $184,500 for 2026; if your other wages already exceed that cap, the NSO income won’t appear here.³
Box 5 (Medicare wages) — no wage cap, so the full spread is included regardless of how much you earn.

The single most common mistake with Code V is treating it as extra income on top of Box 1. It isn’t. If Box 1 shows $120,000 and Code V shows $20,000, your taxable wages are $120,000, not $140,000. The Code V figure is an informational breakout of what’s already inside Box 1.

How Tax Was Withheld on the Exercise

NSO income is treated as supplemental wages for withholding. Your employer typically withholds federal income tax at the flat supplemental rate of 22%. If your total supplemental wages for the year exceed $1 million, the rate on the excess jumps to 37%.⁴

On top of income tax, your employer withholds 6.2% for Social Security (up to the $184,500 wage base) and 1.45% for Medicare. All of the withheld amounts appear in Boxes 2, 4, and 6. The flat 22% supplemental rate may not match your actual marginal bracket. If you’re in the 32% or 35% bracket, expect to owe additional tax when you file. Making an estimated payment in the quarter you exercised can head off an underpayment penalty.

Reporting Code V on Your 1040

You don’t do anything special with Code V on your Form 1040. The income is already inside the Box 1 wages that flow onto Line 1 of your return. There’s no separate line, no attached form for the exercise itself. The reporting work only begins when you sell the shares.

The Cost Basis Trap When You Sell the Shares

This is where Code V matters most, and where most taxpayers get burned. When you sell shares acquired through an NSO exercise, you report the sale on Form 8949, and the totals carry to Schedule D.⁵ The critical figure is your cost basis, and your brokerage will almost certainly understate it on the Form 1099-B.

Your correct cost basis is the exercise price you paid plus the ordinary income you already recognized (the Code V amount). Using the earlier numbers, you paid $10 per share and recognized $40 per share as ordinary income, so your basis is $50 per share. But for options granted after 2013, the IRS requires brokerages to report the basis without including the income you recognized at exercise.⁶ Your 1099-B will likely show a basis of $10, making your gain look $40 per share larger than it actually is.

If you don’t catch it, you pay tax on the $40 spread twice: once as ordinary income at exercise (already in Box 1) and again as capital gain when you sell. To fix it, enter the incorrect basis from the 1099-B in column (e) of Form 8949, put adjustment code “B” in column (f), and enter the correction in column (g). In the example, you’d show $10 in column (e), code B in column (f), and a negative $40 per share adjustment in column (g) to reach the correct gain.⁵

Most tax software will handle the adjustment if you tell it the shares came from an NSO exercise. If you’re filing manually, or if your preparer doesn’t ask, the double-tax error slips through easily. The Code V figure on your W-2 is the number you need to reconstruct the correct basis, so hold onto that W-2 even in years long after the exercise.

Short-Term vs. Long-Term Treatment After Exercise

Any gain or loss beyond the spread you already recognized is capital, not ordinary. The rate depends on how long you held the shares after exercising:

One year or less after exercise — short-term, taxed at your regular income tax rates.⁷
More than one year after exercise — long-term, taxed at 0%, 15%, or 20% depending on your taxable income and filing status.⁷

If the stock drops after you exercise, you can end up with a capital loss even though you already paid ordinary income tax on the spread. That loss offsets other capital gains and up to $3,000 of ordinary income per year, but it doesn’t undo the tax you already paid at exercise. A same-day sale (exercise and immediately sell) avoids this price risk, though it leaves any small gain short-term.

Extra Taxes a Large Exercise Can Trigger

Additional Medicare Tax

On top of the standard 1.45% Medicare withholding, a 0.9% Additional Medicare Tax applies once your wages exceed $200,000 (single) or $250,000 (married filing jointly).⁸ Because the Code V amount is in Box 5, a large NSO exercise can push you across that line. Your employer must start withholding the extra 0.9% once your wages pass $200,000 in a calendar year, regardless of filing status, so married couples who are both under $200,000 individually may need to settle up at filing.

Net Investment Income Tax

When you sell the stock, any capital gain counts as net investment income for the 3.8% Net Investment Income Tax, which applies when modified adjusted gross income exceeds $200,000 (single) or $250,000 (married filing jointly).⁹ NIIT doesn’t apply to the ordinary income at exercise, but a big NSO exercise can lift your AGI enough to pull all your other investment income into the surtax for the year.

Code V Means NSOs, Not Incentive Stock Options

If your W-2 has a Code V, you exercised non-statutory stock options, not incentive stock options. The tax treatment is different in ways that matter. NSOs trigger ordinary income tax at exercise. ISOs generally don’t create a regular income tax event at exercise; the tax is deferred until you sell, and if you meet certain holding periods, the entire gain can qualify for long-term capital gains rates. The trade-off with ISOs is the Alternative Minimum Tax, because the spread on an ISO exercise is an AMT adjustment item. NSOs have no AMT implications, since you’re already paying regular income tax on the spread. If you see Code V, none of the ISO rules apply to those shares.

If the Code V Amount Looks Wrong

Errors in Code V reporting happen more often than you’d expect, especially at companies processing their first wave of option exercises. If the Code V number doesn’t match your own records of the exercise, or if it’s missing entirely, contact your employer’s payroll or HR department and request a corrected W-2.

Your employer issues the correction on Form W-2c. If you’ve already filed for that year, file Form 1040-X and attach Copy B of the W-2c.¹⁰ If you haven’t filed yet, attach both the original W-2 and the W-2c to your return. Employers face penalties for incorrect information returns, which gives payroll a reason to act promptly once you flag the issue.¹¹

1
Internal Revenue Service. General Instructions for Forms W-2 and W-3 (2026) – Section: Box 12 Codes
2
Office of the Law Revision Counsel. 26 USC 83 – Property Transferred in Connection With Performance of Services
3
Social Security Administration. Contribution and Benefit Base
4
Internal Revenue Service. Publication 15 (2026), (Circular E), Employer’s Tax Guide
5
Internal Revenue Service. Instructions for Form 8949 (2025)
6
Internal Revenue Service. 2025 Instructions for Form 8949
7
Internal Revenue Service. Topic No. 409, Capital Gains and Losses
8
Internal Revenue Service. Questions and Answers for the Additional Medicare Tax
9
Internal Revenue Service. Net Investment Income Tax
10
Internal Revenue Service. Form W-2c (Rev. January 2026) Corrected Wage and Tax Statement
11
Internal Revenue Service. Information Return Penalties