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Assessor’s Office

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Physical Address (and FedEx/UPS)
Williams County Administration Building, 1st Floor
206 E Broadway
Williston, ND 58801

Mailing Address
P.O. Box 2047
Williston, ND 58802-2047
Monday – Friday: 8 am – 5 pm


Department Head: Darcy Anderson, Tax Director

The North Dakota Century Code requires the Williams County Assessor's Office to uniformly and fairly value all parcels of land and buildings for tax purposes.

Property valuation is an ongoing process that consists of gathering and reviewing information on properties through field inspections, measuring and listing new construction, and analyzing market sales to determine fair values for existing and new construction properties. The office uses a Computer Assisted Mass Appraisal system to help fairly arrive at a true and full value for each property. Each year, a sales ratio is conducted to determine how close the assessor's values compare to sales and how equitable various types of property are being valued.

All real property subject to taxation is assessed as of February 1st of each year. Any increase of assessment of $3,000 or more, and more than 10% in value, requires a "Notice of Increase" in assessment to be sent to the property owner.

Property taxes are determined by our elected officials (City & County Commissioners, school & park board members , etc.) setting a budget for their political subdivision. That is what determines the total amount of property tax to be paid in any given year in Williams County.

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