GIS Supervisor

Justin Smith

GIS Technician

Kim McFadden

Office Location

117 East High Street, Suite 131
Mount Vernon, Ohio 43050
Phone:  740-393-6752
Fax:  740-397-2723

Office Hours

Monday thru Friday
8:00am to 4:00pm
Closed weekends and holidays

The Tax Map office is responsible for reviewing all new survey drawings and descriptions, including all property transfers that occur in Knox County. We also maintain and update the countys' GIS data layers and manage all GIS applications.

Survey Review

All property transfers must have their descriptions approved by the Tax Map office before the County Auditor will transfer them. Parcels with descriptions that do not meet current standards will have to be surveyed by a Registered Professional Surveyor, and approved by the Tax Map Office. New splits or survey drawings must also be reviewed to make sure they meet minimum state standards for boundary surveys as provided for in Ohio Revised Code, Chapter 4733, as well as several local standards. A copy of the standards is available for viewing and printing by clicking the following link: Transfer Standards.

Assign Property Addresses

The Map Department is also now responsible for assigning house numbers in the County. If you are building a new home, you may download the steps required to build a home worksheet, or an application for a house number, or pick one up at the Map Department located on the first floor of the County Service Center Building 117 E. High Street, Mount Vernon, OH 43050.

Please note you must have an access management permit, or driveway permit before a house number can be assigned. Contact the appropriate office below:

For County roads contact the Engineers office : 740-397-1590

For State roads contact the ODOT Highway Garage: 740-392-3066

For Township roads contact the respective township zoning inspector or township house.


GIS stands for Geographic Information System. This is a form of computerized mapping that incorporates layers of information, such as property lines, subdivision boundaries, topography, soil types, aerial photography, and many others. The map features or layers are linked to a property owner database with information such as owner names, acreage, sale price, etc. This is what makes GIS maps, quote "smart" maps and allows for very detailed analyses to determine trends that would be almost impossible using hard copy information.

The computerized mapping described above can be printed out in a variety of scales and paper sizes depending on one's needs. We do small page printing on demand in our office and also provide customized mapping for those that are interested in having more than just parcels lines and an aerial photo. The entire county GIS data; including aerial imagery, and topography are also available on CD. A free GIS Viewer called ArcExplorer is also available with some of the data. Feel free to ask us more about our data and software and if it will work for your needs. Of course you are always welcome to load our data into your own software applications such as ArcView or AutoCAD.

Our GIS information is available to the public at two workstations in our office in addition to being available on the internet. More information on GIS can be found on our GIS Links & Standards page.

What information do we have?

We keep and archive all survey drawings, road right of way maps, railroad right of way maps, and plat maps (property owner maps) ranging from 1856 to the present. Countywide aerial photos are available for several different years. Knox County Road Maps and Topography maps are also available. Hard copies are available on all of the data. We do not have county plat books for sale. These can be obtained at the Knox County Chamber of Commerce.