Minnesota Stock Options Tax: 9.85% Top Rate, a 6.75% State AMT on ISO Exercises, and QSBS Conformity

Minnesota is one of the more expensive states for tech employees with large stock option grants — but the cost structure is more nuanced than the headline 9.85% rate suggests. The most consequential and least-discussed feature: Minnesota maintains its own alternative minimum tax at 6.75%, and ISO exercise spreads are AMT preference items for Minnesota purposes just as they are federally.¹ A UnitedHealth Group employee exercising $500,000 of ISOs in Minnesota doesn't just face federal AMT — they potentially face a separate Minnesota state AMT bill layered on top. That combination is unusual; states like New York, Massachusetts, Illinois, and New Jersey have no state AMT at all.

The second notable feature: Minnesota provides no preferential rate for long-term capital gains.² A qualifying ISO disposition that generates LTCG at the federal level (taxed at 0%, 15%, or 20% federally) is taxed as ordinary income in Minnesota at rates up to 9.85%. The federal qualifying-disposition benefit exists only at the federal level; Minnesota's take is the same whether you held the shares for one day or ten years.

The one significant offset: Minnesota fully conforms to the federal §1202 QSBS exclusion.³ Startup founders at qualifying C-corps can exclude up to $15M of QSBS gain from both federal and Minnesota income tax — a major advantage over California (which has never conformed to §1202) and Oregon (which decoupled from §1202 in 2026 via SB 1507). For a Minnesota startup founder with a $10M QSBS qualifying sale, this means approximately $985,000 in Minnesota state tax that a California counterpart would owe is instead $0.

There is also a newer layer for high earners: Minnesota enacted a 1% Net Investment Income Tax (NIIT) on investment income exceeding $1 million, effective for tax years beginning after December 31, 2023.⁴ For tech employees with large qualifying dispositions, this pushes the effective Minnesota top rate on capital gains to 10.85% for investment income above the $1M threshold.

The summary: Minnesota is expensive for NQSO exercises and qualifying ISO dispositions, and the state AMT makes large ISO exercises particularly costly. It is meaningfully better than California (lower rate, no ordinary income at ISO exercise, QSBS conformity) but significantly worse than Illinois, and dramatically worse than Texas or Florida for most stock option scenarios. The one planning area where Minnesota genuinely shines: QSBS for startup founders.

Minnesota Income Tax Rates 2026

Minnesota's individual income tax has four progressive brackets for 2026.² For single filers:

• 5.35% on taxable income up to $33,310
• 6.80% on income $33,311 – $109,430
• 7.85% on income $109,431 – $203,150
• 9.85% on income above $203,150

For married filing jointly, the top 9.85% bracket begins at approximately $304,970 (the MFJ thresholds are inflated annually in proportion to the single thresholds).² Minnesota adjusts brackets annually for inflation based on the U.S. Chained CPI; the 2026 brackets represent a 2.369% adjustment from 2025.

Minnesota taxes NQSOs, RSU vesting income, and disqualifying ISO dispositions as ordinary income subject to these brackets. All capital gains — short-term and long-term alike — are subject to the same rate schedule, with no preferential lower rate for long-term holds.

Minnesota's Double AMT Problem for ISO Holders

This is the most important planning distinction for Minnesota ISO holders. Most states either (a) tax ISO exercise spreads as ordinary income at exercise (California), or (b) have no state AMT and no income tax at ISO exercise (New York, Massachusetts, Illinois). Minnesota does neither: it follows federal treatment for regular income tax (no ordinary income at ISO exercise) but maintains its own AMT at 6.75% in which the ISO exercise spread is an AMT preference item.¹

The practical result: a Minnesota ISO holder exercising a large tranche potentially faces federal AMT (26%–28%) and Minnesota state AMT (6.75%) on the same ISO spread. The combined AMT exposure is unique to a small number of states. California imposes its own 7% state AMT on ISO exercises — similar magnitude to Minnesota's 6.75%, though the California AMT is technically imposed on ISO exercises as ordinary income rather than as a separate AMT preference-item calculation.

A critical implication: the disqualifying-disposition analysis for Minnesota ISO holders is more nuanced than for New York or Massachusetts holders. For New York and Massachusetts, the qualifying vs. disqualifying decision is primarily a federal tax question (15%–20% LTCG vs. 37% ordinary income). For Minnesota, a disqualifying disposition eliminates the Minnesota AMT exposure on the spread (by converting it to ordinary income, which is taxed at 9.85% but not as an AMT preference item) — while a qualifying hold incurs both the federal AMT and the Minnesota state AMT, then taxes the eventual qualifying-disposition sale at 9.85% (no LTCG preference). Running both scenarios with a Minnesota tax advisor before exercising is essential for large ISO grants.

NQSO Treatment in Minnesota

Nonqualified stock option exercises generate W-2 ordinary income (the spread between exercise price and FMV at exercise), subject to Minnesota income tax at rates up to 9.85%.² Minnesota also taxes any capital gain on shares held after exercise at ordinary income rates — short-term and long-term gains alike are subject to the full bracket schedule.

ISO Qualifying and Disqualifying Dispositions in Minnesota

Qualifying dispositions

A qualifying ISO disposition — shares held at least 2 years from grant date and at least 1 year from exercise date under IRC §422(a)(1) — is long-term capital gain federally (0%, 15%, or 20%) plus 3.8% NIIT above the threshold. In Minnesota, that same qualifying disposition is taxed at ordinary income rates up to 9.85%, with no LTCG preference.²

For large qualifying dispositions where investment income exceeds $1 million in the year, Minnesota's 1% NIIT surtax applies on top, pushing the effective Minnesota rate to 10.85% on the incremental amount.⁴ A senior engineer with a $2M qualifying ISO sale who has $200K of other investment income would pay Minnesota tax at 9.85% on the first ~$800K of capital gain income (before the $1M threshold) and 10.85% on the remaining ~$1.2M — approximately $195,800 in total Minnesota state tax on the $2M gain, plus any applicable federal tax.

Disqualifying dispositions

A disqualifying disposition (selling ISO shares before satisfying the 2-year/1-year holding requirements) converts the exercise-date bargain element to W-2 ordinary income — reported on your W-2, subject to Minnesota income tax at up to 9.85%. Any additional gain above exercise-date FMV becomes short-term capital gain, also taxed at ordinary income rates in Minnesota. There is no FICA on the disqualifying disposition spread per IRC §3121(a)(22)(B), but the full spread is subject to Minnesota income tax.

Paradoxically, for a Minnesota ISO holder who exercises a large tranche and triggered Minnesota AMT on the exercise, a subsequent disqualifying disposition can generate a Minnesota AMT credit carryforward. The credit arises because the disqualifying disposition converts what was previously an AMT preference item into regular income — reducing or eliminating the future AMT that would otherwise have shadowed the qualifying-disposition sale.

Minnesota's 1% Net Investment Income Surtax

Minnesota enacted a 1% Net Investment Income Tax (NIIT) effective for tax years beginning after December 31, 2023.⁴ The surtax applies to net investment income — including dividends, interest, and capital gains — exceeding $1 million in a taxable year. It is not the same as the federal 3.8% NIIT (which has different thresholds and rules); this is a separate Minnesota state-level charge.

For stock option holders, the Minnesota NIIT matters most in years with large qualifying ISO dispositions or NQSO exercises where capital gains from share sales push total investment income above $1M. In those years, the effective Minnesota marginal rate on investment income above $1M is 10.85% (9.85% regular tax + 1% NIIT). The $1M threshold is applied to net investment income, not to all income — so a tech employee with $180K salary and a $1.3M qualifying ISO sale would have approximately $1.3M of investment income, with $300K subject to the 1% surtax above the threshold.

QSBS in Minnesota: Full Federal Conformity

Minnesota conforms to the federal §1202 QSBS (qualified small business stock) exclusion.³ A Minnesota resident who sells qualifying QSBS and excludes gain at the federal level under §1202 also excludes that gain from Minnesota taxable income — the excluded amount is simply not in federal AGI, which is Minnesota's starting point for income calculation.

For 2026, this conformity applies to the OBBBA-era §1202 rules: tiered exclusions of 50%/75%/100% at 3/4/5 years of holding, with a $15M gain cap (or 10× adjusted basis) and a $75M gross asset limit for qualifying issuances after July 4, 2025. Gains excluded federally are excluded from Minnesota income tax at the same amount. Minnesota state tax on federally excluded QSBS gain: $0.

Minneapolis and St. Paul: No City Income Tax

Neither Minneapolis nor St. Paul imposes a city income tax on stock option income.⁵ Unlike New York City (which adds up to 3.876% on option income, pushing the combined NYC rate to 14.776%) or Portland, Oregon (which layers a 1% Metro SHS + up to 3% Multnomah County PFA on top of the 9.9% Oregon rate), Minnesota's Twin Cities impose no percentage-based city income tax. Stock option income is taxed at the state level only.

This is an often-overlooked advantage compared to the full New York City or Portland effective rate. A UnitedHealth employee in Minnetonka exercising $500K of NQSOs pays ~$49,250 in Minnesota state tax; if they had the same exercise as a New York City resident, they would pay approximately $54,500 (state) + $19,380 (NYC) = $73,880. Minneapolis's absence of city income tax is a real planning factor for employees weighing the Twin Cities versus New York.

Nonresident Sourcing: Minnesota's Workday Fraction and the ISO Exception

Minnesota taxes nonresidents on income sourced to Minnesota based on the proportion of workdays performed in Minnesota during the option's allocation period.⁶ For NQSOs, RSUs, and other equity-based awards treated as W-2 compensation, the allocation period runs from grant date through the earlier of (a) vesting/substantial vesting or (b) sale of the shares:

MN-source income = total option spread × (Minnesota workdays during allocation period ÷ total workdays during allocation period)

Former Minnesota residents who relocated after receiving NQSO grants still owe Minnesota tax on the Minnesota-workday fraction when they exercise — even years after leaving.

The ISO statutory option exception for nonresidents

There is an important distinction for ISO holders. Under Minnesota Department of Revenue guidance, income recognized by a nonresident on the sale of stock purchased through statutory stock options (ISOs) is generally not assigned to Minnesota and is not subject to Minnesota income tax withholding.⁶ This treatment differs from NQSOs and RSUs, where the W-2 compensation element is allocated using the workday fraction.

The practical implication: a former Minnesota resident who exercised ISOs while living in Minnesota and has since relocated may not owe Minnesota nonresident income tax when they sell those ISO shares — whereas a former Minnesota NQSO holder would owe tax on the Minnesota-workday fraction. This is a nuanced and fact-specific analysis; the ISO exception for nonresidents and the state AMT question should be reviewed with a Minnesota-licensed tax advisor before making sale-year decisions.

Six Planning Strategies for Minnesota Stock Option Holders

1. Model both the federal AMT and the Minnesota 6.75% state AMT before exercising ISOs

Most ISO exercise planning frameworks focus only on the federal AMT. In Minnesota, that is insufficient. Use the ISO AMT Calculator to establish the federal AMT breakeven (the number of ISO shares you can exercise before triggering any federal AMT at your income level). Then separately model the Minnesota state AMT at 6.75% — whether the full exercise spread exceeds the Minnesota AMT exemption and generates a Minnesota AMT bill above and beyond the federal calculation. A large exercise that is "within the federal AMT safe zone" may still generate a meaningful Minnesota state AMT charge. Consult a Minnesota-licensed CPA before exercising more than $200,000–$300,000 of ISO spread in any single year.

2. Run the qualifying-vs-disqualifying disposition analysis with Minnesota AMT in mind

For New York and Illinois ISO holders, the qualifying vs. disqualifying disposition is primarily a federal question (20% LTCG vs. 37% ordinary income). For Minnesota holders, two additional factors change the math: (a) Minnesota provides no LTCG preference, so the qualifying-disposition path creates both the federal AMT at exercise AND Minnesota AMT at exercise, then taxes the eventual sale at 9.85%; (b) a disqualifying disposition eliminates the AMT preference item treatment (converting it to regular income taxed at 9.85%) and generates a Minnesota AMT credit for the AMT previously paid. For some scenarios — particularly when the federal AMT is large, the Minnesota AMT is large, and the qualifying-disposition tax rate equals the disqualifying-disposition rate at the state level (9.85% either way) — the disqualifying disposition may be the better total-tax outcome despite the loss of federal LTCG treatment. Work with an advisor who can model the full federal + state AMT picture across multiple years.

3. Use QSBS conformity for pre-IPO and early-exercise planning at qualifying startups

Minnesota's full conformity to §1202 makes early exercise + 83(b) election an especially powerful strategy for founders and early employees at qualifying C-corps in the Twin Cities. If you have early-exercise rights on ISO or NQSO grants at a startup meeting the §1202 requirements ($75M or less in gross assets at issuance, qualifying business type, domestic C-corp, etc.), exercising immediately at grant and filing an 83(b) election within 30 days starts the QSBS clock. After 5+ years (for post-OBBBA stock), the entire gain — up to $15M — is excluded from both federal and Minnesota income tax. On a $10M qualifying gain, that is approximately $985,000 in Minnesota state tax avoided compared to a scenario where the gain is treated as ordinary income. The 30-day 83(b) window is a hard deadline.

4. Consider the 1% Minnesota NIIT when planning large qualifying dispositions

In years where you expect more than $1 million of net investment income — from ISO qualifying dispositions, NQSO-generated capital gains, dividends, or other sources — factor in the 1% Minnesota NIIT on income above the $1M threshold. For large sales this may be unavoidable, but in multi-year exercise strategies (spreading ISO exercises and share sales across 2–3 years), keeping annual investment income below $1M avoids the surtax entirely. On a $3M qualifying ISO gain that could be spread over two tax years, keeping each year below $1M of investment income saves approximately $10,000–$20,000 in additional Minnesota NIIT.

5. If you recently relocated from Minnesota, calculate your NQSO sourcing ratio before exercising

At 9.85%, Minnesota's nonresident sourcing creates a significant dollar exposure on large NQSO exercises. Every month worked outside Minnesota after your grant date increases the denominator of the sourcing fraction and reduces the Minnesota-source income. If you relocated within the past 1–4 years and hold large unexercised Minnesota-era grants, calculate your current grant-to-exercise sourcing ratio and the Minnesota nonresident tax at that ratio versus waiting 6–12 months. Compare the incremental Minnesota tax savings from a shorter ratio against the stock price risk during the wait period. For former Minnesota residents in Texas or Florida (no offsetting state tax credit), the Minnesota nonresident bill is the full economic cost — unlike California-to-New York moves where the states each allow a credit for taxes paid to the other.

6. Review the ISO nonresident exception before selling post-move

If you exercised ISOs while a Minnesota resident and subsequently relocated before selling the shares, review the Minnesota statutory option nonresident exception with a Minnesota CPA before you sell. The general rule that NQSO and RSU income is sourced to Minnesota based on workdays does not necessarily apply to ISO share sales for nonresidents under the same framework. The distinction between statutory option treatment and nonstatutory option treatment in Minnesota's nonresident sourcing rules can affect whether a large ISO share sale triggers a Minnesota nonresident return at all. Do not assume that the same sourcing analysis you apply to NQSOs applies to your ISO shares.

1. Minnesota individual AMT at 6.75%, ISO spread as MN AMT preference item. Minnesota imposes a state alternative minimum tax under Minn. Stat. §290.091 at a rate of 6.75% on alternative minimum taxable income above the Minnesota AMT exemption. ISO exercise spreads are AMT preference items under IRC §56(b)(3) (incorporated into Minnesota's AMT calculation), meaning ISO exercises trigger potential MN AMT liability even though no regular Minnesota income tax is due at exercise. The MN AMT credit (§290.0921) allows recovery of MN AMT paid in prior years against future regular tax liability. Sources: Minnesota Department of Revenue — Alternative Minimum Tax; Minn. Stat. §290.091 — Individual Minimum Tax (Minnesota Legislature); Minnesota Department of Revenue — Alternative Minimum Tax Credit.
2. Minnesota 2026 income tax brackets and no LTCG preference. Minnesota taxes all income — wages, ordinary income, and capital gains (both short-term and long-term) — at the same progressive rates. No preferential rate for long-term capital gains. 2026 brackets for single filers: 5.35% ($0–$33,310), 6.80% ($33,311–$109,430), 7.85% ($109,431–$203,150), 9.85% (over $203,150). Brackets inflated annually by Chained CPI (2.369% adjustment from 2025). Sources: Minnesota Department of Revenue — 2026 Income Tax Brackets Press Release (Dec 2025); Minnesota Department of Revenue — Income Tax Rates and Brackets.
3. Minnesota §1202 QSBS conformity. Minnesota conforms to the federal qualified small business stock exclusion under IRC §1202. Because Minnesota's individual income tax begins with federal adjusted gross income (Minn. Stat. §290.01, subd. 19), gains excluded from federal AGI under §1202 are also excluded from Minnesota taxable income. Minnesota conforms to the OBBBA-era §1202 rules (effective July 4, 2025): tiered 50/75/100% exclusion at 3/4/5 years, $15M gain cap, $75M gross asset limit at issuance. Sources: Keystone Global Partners — 2026 QSBS by State: Eligibility Index; The Startup Law Blog — 2026 QSBS State-by-State Conformity Guide.
4. Minnesota 1% Net Investment Income Tax (NIIT). Minnesota enacted a 1% surtax on net investment income exceeding $1 million for taxable years beginning after December 31, 2023 (continuing through 2026). Net investment income includes dividends, interest, and capital gains. The surtax applies only to the amount exceeding $1M and is separate from the federal 3.8% NIIT. Sources: Minnesota Department of Revenue — Net Investment Income Tax (NIIT); Boyum Barenscheer — Minnesota Net Investment Income Tax: What High Income Investors Need to Know in 2026.
5. No city income tax in Minneapolis or St. Paul. Neither the City of Minneapolis nor the City of Saint Paul imposes a city income tax or percentage-based surcharge on wages or investment income. Minnesota local governments do not have authority to impose income taxes under current state law. Source: Minnesota Department of Revenue — Individual Income Tax Overview.
6. Minnesota nonresident sourcing: NQSO workday fraction and ISO statutory option exception. For non-statutory stock options, RSUs, and other equity-based compensation, Minnesota sources income to Minnesota using the ratio of Minnesota workdays to total workdays during the allocation period (grant through vesting or sale). Income recognized by a nonresident on the sale of stock purchased through statutory stock options (ISOs) is generally not assigned to Minnesota and is not subject to MN income tax withholding — a distinct treatment from NQSO/RSU sourcing. Nonresidents with MN-source income file Form M1NR. Sources: Minnesota Department of Revenue — Nonresidents Working in Minnesota; Minnesota Department of Revenue — How Minnesota Taxes Nonresident Income; Financial Planning Association — State Income Taxation of Nonresident Equity-Based Compensation (Oct 2022).

Values verified May 2026. Minnesota 2026 income tax brackets from Minnesota Department of Revenue December 2025 press release; state AMT rate from Minn. Stat. §290.091; NIIT from Minnesota Department of Revenue guidance. The Minnesota state AMT interaction with specific ISO exercise scenarios requires verification with a Minnesota-licensed tax advisor. Confirm current-year values before making irreversible decisions.