Minnesota’s corporate income tax, which the state calls the Corporate Franchise Tax, applies a flat 9.8% rate to the share of a C-corporation’s income connected to Minnesota.1Minnesota Office of the Revisor of Statutes. Minnesota Statutes 290.06 – Computation, Corporations On top of that, corporations compute a 5.8% alternative minimum tax on a broader income base and pay the higher of the two, owe a tiered minimum fee based on in-state property, payroll, and sales, and make quarterly estimated payments. Calendar-year returns are due April 15, with a seven-month filing extension available if the tax is paid by the original deadline.
Which Businesses Owe the Tax
Any C-corporation doing business in Minnesota or earning income from Minnesota sources must file. The trigger is nexus, meaning enough connection to the state for Minnesota to assert taxing authority under Minn. Stat. ยง 290.015. Physical presence counts: owning or leasing property, having employees in the state, or storing inventory here all create nexus. So does serving Minnesota customers, even with every employee working remotely from another state.2Minnesota Department of Revenue. Nexus and Business Income Tax
Federally tax-exempt organizations such as charities are generally excluded.3Minnesota House of Representatives. Corporate Franchise Tax S-corporations don’t pay the franchise tax on income because their profits flow through to shareholders, but they can still owe the minimum fee. Partnerships and LLCs that have elected corporate tax treatment follow the C-corporation rules.
The 9.8% Rate and the Alternative Minimum Tax
Minnesota applies a flat 9.8% to all taxable income apportioned to the state, with no graduated brackets. A corporation with $50,000 of Minnesota taxable income pays the same percentage as one with $50 million.1Minnesota Office of the Revisor of Statutes. Minnesota Statutes 290.06 – Computation, Corporations
Every corporation also computes an alternative minimum tax at 5.8% on a broader income base, which typically allows less generous depreciation. If the AMT produces a higher number than the regular tax, the corporation pays the AMT amount.3Minnesota House of Representatives. Corporate Franchise Tax The AMT catches companies that drive taxable income low through aggressive deductions but still have substantial economic income tied to Minnesota.
The Minimum Fee for 2026
Every corporation, S-corporation, and partnership filing in Minnesota owes a minimum fee based on the combined total of its Minnesota property, payroll, and sales. It is in addition to the regular tax or AMT. Brackets adjust annually for inflation.4Minnesota Office of the Revisor of Statutes. Minnesota Statutes 290.0922 – Minimum Fee For tax year 2026:5Minnesota Department of Revenue. Minimum Fee
- Less than $1,280,000: $0
- $1,280,000 to $2,559,999: $260
- $2,560,000 to $12,829,999: $770
- $12,830,000 to $25,639,999: $2,560
- $25,640,000 to $51,279,999: $5,140
- $51,280,000 or more: $12,830
Businesses below the first threshold owe nothing.
How Minnesota Decides What Income It Can Tax
Since 2014, Minnesota has used a single sales factor to apportion the income of multistate corporations. Property and payroll locations don’t enter the formula. Divide Minnesota sales by total sales everywhere, and the resulting percentage is applied to the corporation’s total taxable income.6Minnesota Office of the Revisor of Statutes. Minnesota Statutes 290.191 – Apportionment Formula A company with $10 million in total sales and $3 million delivered to Minnesota customers apportions 30% of its income to the state. Tangible goods are sourced to Minnesota when delivered to a buyer here; services are sourced to Minnesota when the customer receives the benefit of the service in the state.7Minnesota House of Representatives. Apportionment of Corporate Franchise Tax
The starting point for the income being apportioned is federal taxable income from the IRS return, with Minnesota-specific additions and subtractions on top.
Adjustments That Change the Federal Number
Bonus Depreciation Add-Back
Minnesota requires corporations to add back 80% of the bonus depreciation claimed on the federal return, then recover that amount at 20% per year over the next five tax years. If you sell the asset during that window, you still follow the original five-year subtraction schedule.8Minnesota Department of Revenue. Recalculate Bonus Depreciation It’s a timing difference, not a permanent tax increase, but a year of heavy capital investment will produce a Minnesota tax bill noticeably larger than the federal picture suggests.
Net Operating Losses
Corporations can carry forward net operating losses for up to 15 years. The deduction in any given year is capped at 70% of that year’s taxable net income, and there is no carryback.9Minnesota Office of the Revisor of Statutes. Minnesota Statutes 290.095 – Net Operating Loss Deduction Multistate corporations deduct the loss at the apportionment percentage from the year the loss arose, not the year it’s used, which matters when Minnesota sales share shifts year to year.
Combined Reporting for Affiliated Groups
When two or more corporations operate as a single economic unit, Minnesota treats them as a unitary business and requires one combined franchise tax return. The test looks at common ownership, shared management, and interdependent operations, and typical parent-subsidiary structures almost always qualify.10Cornell Law Institute. Minnesota Rules 8019.0405 – Combined Report Filing Group income is pooled and apportioned to Minnesota using the combined sales factor, which prevents profit shifting to lower-tax affiliates. Foreign corporations organized outside the U.S. are generally excluded from the combined report and file separately if they have their own Minnesota filing requirement.11Minnesota Department of Revenue. Analysis of H.F. 2883 – Combined Worldwide Reporting
Credits That Reduce the Tax
The most widely used credit is the Credit for Increasing Research Activities: 10% of qualified research expenses up to a $2 million base amount, and 4% of expenses above that. The research must be conducted in Minnesota. Unused credit carries forward 15 years, and starting with tax year 2025 a portion of unused current-year credit is refundable. For 2026, the refundable rate is 25%.12Minnesota Department of Revenue. Credit for Increasing Research Activities
Other credits include the Angel Tax Credit for investments in qualifying startups, a 25% film production credit on projects spending at least $1 million, and credits tied to business expansion in Greater Minnesota and border communities. Availability changes periodically and some credits carry annual caps or require advance certification, so verify current rules with the Department of Revenue before claiming.
Quarterly Estimated Payments
Corporations pay estimated franchise tax in four installments, due on the 15th day of the 3rd, 6th, 9th, and 12th months of the tax year. For calendar-year filers, that’s March 15, June 15, September 15, and December 15.13Minnesota Office of the Revisor of Statutes. Minnesota Statutes 289A.26 – Payment of Estimated Tax by Corporations Each installment is 25% of the required annual payment, which is the lesser of 100% of the current year’s tax or 100% of the prior year’s tax, provided the prior year covered a full 12 months and showed some liability.
Large corporations face a tighter rule. If taxable net income reached $1 million or more in any of the three preceding years, the prior-year safe harbor is available only for the first installment. After that, payments must be based on current-year income, and any first-quarter shortfall must be made up in the second installment.13Minnesota Office of the Revisor of Statutes. Minnesota Statutes 289A.26 – Payment of Estimated Tax by Corporations
Filing the Return
Corporations file Form M4, which begins with federal taxable income from Form 1120 and then applies the Minnesota additions, subtractions, and apportionment.14Minnesota Department of Employment and Economic Development. Business Income Tax Returns The return goes through the Department of Revenue’s e-Services portal or approved tax software.
Calendar-year corporations file by April 15. An automatic seven-month extension pushes the filing deadline to November 15 as long as estimated tax is paid by April 15.15Minnesota Department of Revenue. Tax Due Dates Fiscal-year filers follow the same pattern using the 15th day of the fourth month after year-end. The extension gives more time to file; it does not extend the payment deadline.
Corporations that paid more than $10,000 in estimated franchise tax during the previous state fiscal year (July 1 through June 30) must make all payments electronically. Once triggered, the electronic requirement is permanent.16Minnesota Department of Revenue. Electronic Payment for Business Taxes
Penalties Stack
Unpaid franchise tax after the due date triggers a 6% late-payment penalty on the unpaid balance, waivable only if certain estimated payment requirements were met. Filing the return late adds a separate 5% penalty on the unpaid tax, and a return filed after the original due date (ignoring extensions) without full payment adds another 5% on the remaining balance. The penalties are additive, so a corporation that files late and pays late can see combined penalties of 16% of the unpaid tax before interest, which accrues at a rate the Department of Revenue sets quarterly.17Minnesota Office of the Revisor of Statutes. Minnesota Statutes 289A.60 – Civil Penalties
If you need the seven-month extension to finish the return, pay your best estimate of the balance due by the original deadline. The extension protects against the late-filing penalty. It does nothing for the late-payment penalty.