Grand Forks apartment property taxes are calculated by valuing the building every year as of February 1, cutting that value in half to get assessed value, and then applying a 10% taxable ratio because North Dakota treats buildings with four or more units as commercial property. The resulting taxable value is multiplied by the combined mill levy of the city, school district, county, park district and state, which totaled 343.11 mills inside Grand Forks for 2025.
That sequence sounds simple, but each step has rules, deadlines and appeal rights that matter to an owner. This guide walks through them in order, using North Dakota statutes, State Tax Commissioner guidance and the City of Grand Forks Assessing Department’s own reports.
Who values apartment buildings in Grand Forks
Inside city limits, the City of Grand Forks Assessing Department is responsible for finding, listing and valuing all real property. It appraises new construction every year and verifies exemptions and credits. Outside the city, township assessors handle that work. At the county level, the Grand Forks County Tax Equalization Office works with city and township assessors to keep values uniform across jurisdictions and prepares the annual tax statements.
The city’s workload is substantial. Its 2025 annual report says the department valued about 17,441 properties and sent 1,468 notices of increase that year. Residential properties are reappraised on a six-year cycle, while every parcel is still listed and valued annually. For apartment owners, that means the city may revisit a building’s data on a rolling basis even in years when nothing about the property has changed.
Why buildings with four or more units are taxed as commercial
The single most important rule for apartment owners in North Dakota is the classification line between residential and commercial property. Under the definitions in North Dakota Century Code Chapter 57-02, “residential property” does not include structures providing living accommodations for four or more separate family units. The State Tax Commissioner’s guideline on residential and commercial property applies the same line: duplexes and triplexes remain residential, while buildings with four or more family units are classified as commercial.
The classification matters because North Dakota applies different taxable-value ratios to each class:
- Residential property: taxable value equals 9% of assessed value.
- Commercial property, including apartment buildings with four or more units: taxable value equals 10% of assessed value.
- Agricultural and centrally assessed property: also 10% of assessed value.
Because assessed value is half of true and full value, the city describes the effective ratios as 4.5% of market value for residential property and 5% for commercial property. In other words, a fourplex or larger building with the same market value as a triplex will carry a taxable value about 11% higher, and a tax bill about 11% higher, before any other differences.
From market value to tax bill: the Grand Forks formula
The calculation runs in four steps. The city’s taxable value page publishes the same method with its own examples.
- Step 1: True and full value. The assessor estimates market value as of February 1.
- Step 2: Assessed value. State law sets assessed value at 50% of true and full value.
- Step 3: Taxable value. Multiply assessed value by 10% for commercial property, including apartment buildings with four or more units.
- Step 4: Tax. Multiply taxable value by the total mill levy, where one mill equals $1 of tax for every $1,000 of taxable value.
The city’s 2026 worked example uses a property valued at $150,000 and the 343.11-mill rate. As residential property, the tax comes to $2,315.99. As commercial property, it comes to $2,573.33. Both figures are before the 5% early-payment discount.
An illustrative apartment example
Applying the same published formula to a hypothetical apartment building with a true and full value of $3,000,000:
- Assessed value: $3,000,000 × 50% = $1,500,000.
- Taxable value: $1,500,000 × 10% = $150,000.
- Tax at 343.11 mills: $150,000 × 0.34311 = about $51,467.
- With the 5% discount for paying in full by February 15: about $48,893.
That works out to an effective rate of roughly 1.72% of market value before the discount. The city’s 2025 annual report lists an effective tax rate of 1.73% for commercial property and 1.56% for residential property in 2024, so the example sits in line with the city’s own figures. The example excludes special assessments, which are billed separately on the same statement.
What the city’s tax base looks like
The same Grand Forks Assessing Department 2025 annual report gives a sense of scale. Total taxable value in the city reached about $297.47 million in 2025, up 4.42% from the prior year, and commercial property, the class that includes apartment buildings with four or more units, accounted for about $130.2 million of that total. The median commercial property value was $602,500.
Those figures help explain why classification carries real money. Using the published formula and the 343.11-mill rate, a property valued at $600,000 would owe about $10,293 as commercial property and about $9,264 if it were residential, a difference of roughly $1,000 a year on the same market value. For a larger building, the gap grows in proportion.
The mill levy: who sets each piece
The mill levy is not one number set by one body. It is the sum of separate levies adopted by each taxing district. The city’s 2025 annual report breaks down the 2024 total of 346.54 mills for property inside Grand Forks:
- City of Grand Forks: 92.25 mills
- Grand Forks Public Schools: 130.50 mills
- Grand Forks County: 85.00 mills
- Grand Forks Park District: 36.79 mills
- State Medical Center and Garrison Diversion: 2 mills combined
For 2025, the city’s current mill rate page lists a combined rate of 343.11 mills, a small decline from 2024. Looking ahead, Grand Forks County’s 2026 budget document shows a total county levy of 89.22 mills, down from 91.55 in 2025, though some of the county’s individual levies apply to different taxable bases, so not every piece applies inside city limits in the same way. The city’s own budget handout shows a city levy of 91.94 mills for its 2026 budget and an estimated 91.84 mills for 2027, with one mill expected to raise about $319,175 in 2027.
Owners should keep in mind that a falling mill rate does not guarantee a falling bill. If a building’s value rises faster than the mill rate declines, taxes still go up. That is why reviewing the annual valuation notice matters as much as following budget hearings.
How the 2025 legislative changes affect apartment owners
North Dakota’s 2025 Legislature passed a major property tax package, House Bill 1176, which Governor Kelly Armstrong signed on May 3, 2025. According to the governor’s office announcement, the bill did three things that matter here:
- Raised the Primary Residence Credit from $500 to $1,600.
- Capped growth in local property tax budgets at 3% a year, with unused capacity able to carry forward for up to five years. The cap applies to levies on residential, commercial and agricultural property alike.
- Expanded the renter’s refund program for eligible tenants.
The Primary Residence Credit is limited to an owner’s own primary residence, one per household, and requires an application between January 1 and April 1. Apartment buildings held as rental property do not qualify, so this credit lowers homeowners’ bills without changing the commercial calculation for a 12-unit building.
The 3% cap is more relevant to apartment owners. It limits how fast each taxing district’s property tax budget can grow, which indirectly limits how quickly total levies can rise even as values climb. It does not cap the value of any individual building or the tax on it.
Voters also rejected a more drastic change. In November 2024, statewide Measure 4, which would have prohibited property taxes based on assessed value, was rejected by a wide margin. Property tax remains the main revenue source for Grand Forks’s local governments, and the assessment rules described here remain in force.
The calendar every Grand Forks owner should know
Property tax administration in North Dakota follows a fixed annual schedule. For apartment owners, these are the dates that matter:
- February 1: the valuation date. Every parcel is listed and assessed according to its value on this date.
- Before the city board meets: if your value goes up, the assessor must deliver a notice of increase at least 15 days before the local board of equalization meets.
- Early April: the City of Grand Forks Board of Equalization meets during the first half of April. In 2026 it met on April 6 at 5:30 p.m., and written appeals were due to the Assessing Department by 5:00 p.m. that day.
- June: the Grand Forks County Board of Equalization reviews values.
- August: the State Board of Equalization meets on the second Tuesday of August.
- January 1 of the following year: taxes become due.
- February 15: paying the full real estate tax by this date earns a 5% discount. The discount does not apply to special assessment installments.
- March 1 and October 15: if you pay in two installments, the first becomes delinquent after March 1 and the second after October 15, with penalties set in Century Code Chapter 57-20.
Appealing a Grand Forks apartment valuation
The appeal process has a strict order, and skipping a step can forfeit relief. An owner who believes a building is overvalued should start with the City Board of Equalization in April. From there, the owner can go to the county board in June and then to the State Board of Equalization in August.
The State Board can lower an individual property’s value only if the owner first appealed to the city board and then the county board. State Board records include a 2024 Grand Forks appeal on which the board took no action because the owner had not gone to the city board first. That case is a useful warning: the April deadline is the one that counts.
Building a strong apartment appeal
Assessors in North Dakota can use three valuation approaches: cost, sales comparison and income. The State Tax Commissioner’s guideline discusses gross rent and gross income multipliers for rental property and cautions that rent alone should not be treated as the only measure of value. For an apartment building, a well-supported appeal usually includes:
- A current rent roll and the trailing 12 months of income and expenses.
- Evidence of vacancy, concessions and bad debt that reduce collected income below scheduled rent.
- Documentation of deferred maintenance or major capital needs, such as roofs, boilers or parking lots.
- Recent sales of comparable apartment buildings in Grand Forks, with adjustments for age, size and condition.
- A calculation of net operating income and a market-supported capitalization rate.
Owners who prepare these numbers before the notice arrives are in a far better position to meet the April deadline than those who start after it.
Abatement after the bill arrives
If the appeal window has passed, North Dakota also allows an application for abatement under Century Code Chapter 57-23. The application is filed in writing with the county auditor by November 1 of the year after the tax becomes delinquent. The city’s governing body holds a hearing and makes a recommendation, and the county commission decides. Grounds include an assessment that is invalid, inequitable or unjust. Abatement is a narrower remedy than the April appeal, so owners should not rely on it as a substitute.
Special assessments on Grand Forks apartment properties
Property taxes are only part of the bill. The City of Grand Forks funds many street, water, sewer and other improvements through special assessments levied against the properties that benefit. According to the city’s special assessment process page, the Special Assessment Commission assigns benefits at hearings usually held in late September, and the City Council certifies the assessments at its second meeting in October. Owners can prepay without interest during the last two weeks of October. Unpaid balances are spread into yearly installments on the property tax statement.
For apartment owners, special assessments can be a meaningful line item, especially after major street reconstruction. Because the 5% early-payment discount does not apply to them, owners who prepay their taxes should budget for special assessment installments separately.
Managing Grand Forks apartment property taxes: key takeaways
A few lessons follow from the way Grand Forks taxes apartment buildings:
- Know your classification. A triplex is residential at a 9% taxable ratio; a fourplex or larger building is commercial at 10%. Converting or combining buildings can change the class and the bill.
- Read the notice of increase. It arrives before the April city board, and the city board is the first and most important place to contest a value.
- Track mill levies and values together. A lower total mill rate can still mean a higher bill if the valuation rises.
- Budget for special assessments. They are billed on the same statement but follow their own schedule and are not covered by the early-payment discount.
- Expect a buyer to underwrite taxes carefully. Because buildings are revalued annually, a buyer will typically estimate taxes from the current value, the current mill rate and any pending special assessments rather than relying on an old bill.
Owners comparing Grand Forks’s approach with other states can review our overview of rent control and property tax rules by state. For local buyer activity, values and options when it is time to exit, see our Grand Forks market page, and for the wider state picture, our North Dakota apartment market overview.
