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Research Aid: Property Tax Rolls and Assessment Lists

Tax rolls and assessment lists are among the best sources for determining the age of a historic building. They are also useful for determining chain of ownership of a property and for plotting the development of an area or neighborhood.


Finding the Records

Ordinarily the assessor of a township or municipality produced three copies of the property assessments for a given year: an assessment list that was subject to correction and two tax rolls. The tax rolls and the corrected assessment list are substantially identical. Normally a copy of the tax roll became part of the county clerk or treasurer’s records. The other copy and/or the assessment list remains with the township or municipality.

If tax records have not been transferred to a local repository/archives, the next place to look for them is at the county courthouse. If the records are not available at the courthouse, you should check the town, village, or city clerk’s office in the locale you are researching. Many of these local offices maintain tax rolls or assessment lists dating back to the organization of the township or municipality.


Gathering and Analyzing Data

Once you have located the tax rolls for the area you are interested in, you will need to do a little background investigation. The first thing you need to know is the legal description of the parcel. For a parcel in a municipality, you will need the block numbers and the name of the appropriate plat or subdivision. If the building you are researching predates the platting or subdividing of the municipality, you will also need the geographic description of the parcel: its town, range, section, and quarter section. If the parcel does not lie in a municipality, the town, range, section, and quarter section will suffice. The property abstract should provide you with this information. If you do not have an abstract, consult the Register of Deeds at the courthouse.

Next, select a time frame for your research. The time frame you choose should be broad enough to include any remotely possible date of the building’s construction. It is usually advisable to begin with the earliest available tax roll and to extend your research for twenty or more years after the suspected time of construction. This will allow you to spot whatever development may have occurred on the site in the years prior to the building’s construction, and also give you a reasonable certainty of finding construction within the time frame. If, while you are collecting your data, you do not find the expected jump, you should then extend the time frame until you do.

Now you are ready to collect your data. Beginning with the earliest usable tax roll, find the assessment for the parcel you are researching. This sometimes takes a bit of scanning through the list, as various assessors organized the lists differently. Occasionally an area was laid out in government lots prior to subdivision, and you may have to determine which government lot the parcel was in. If such is the case, check with the Register of Deeds.

Record the acreage, the assessed valuation, the owner’s name, and the name of the person who paid the tax for each year within the time frame. If for a time the parcel was part of a larger piece of property or assessed in a combination with other parcels held by an individual, make a note of that fact and of any other information you find which seems important.


Capabilities and Limitations

Property assessments are useful for dating old buildings because they reflect capital improvements to a parcel of land. Most often a substantial jump in the value of a parcel from one year to the next indicates that construction has occurred. Further, tax rolls and assessment lists name the owner of a parcel and/or the person who paid the tax on it in a particular year. Taken over a succession of years, this information can be used to establish a chain of ownership. Finally, assessments over time for a number of neighboring parcels can be studied to determine the pattern of development for an entire area or neighborhood.

Although analysis of tax records is essentially straightforward, there are potential pitfalls to be aware of. First, the change in property assessments over time actually indicates a couple of things in addition to property improvement. General economic trends of inflation and recession drive the assessed valuation of real estate up and down. Periodic reassessments revise assessments which then, barring any capital improvements, remain stable until the next periodic assessment. Therefore, when analyzing assessment data, it is advisable to keep an eye on the economic trends in the area.

Second, when using tax rolls to determine chain of ownership, be aware that the owner of record is not always the person who pays the tax on it. Sometimes knowing that an individual who did not hold title to a parcel was paying tax on it can lead to some interesting speculations, although it would be impossible to draw conclusions from such information without other evidence.