County GIS · State lines · October 21, 2026
North Dakota–South Dakota Border Counties: Parcel Maps
All 16 counties on the North Dakota–South Dakota line, with seats, populations and each official parcel map, plus what changes at the line.
Looking for the counties on the North Dakota–South Dakota border and their parcel maps? According to the Census Bureau's county adjacency file, 8 North Dakota counties touch 8 South Dakota counties along the line. Each one keeps its own property records and its own parcel viewer, so land near the line often means checking two counties in two states.
A farm, hunting tract or lake lot can sit in one state while the road, the neighbors or the rest of the property are in the other. This page lists every county that touches the line on either side, with links to each official parcel map.
North Dakota–South Dakota border at a glance
- Counties on the line: 16 (8 in North Dakota, 8 in South Dakota)
- With a verified public parcel viewer in our directory: 16 of 16
- Residents, 2023 estimates: about 39,619 on the North Dakota side and 63,943 on the South Dakota side
- Most populous on each side: Richland County, ND (16,558) and Brown County, SD (37,733)
- Largest by land area: Emmons County, ND (1,510 sq mi) and Perkins County, SD (2,870 sq mi)
North Dakota counties on the line
| County | Seat | Land (sq mi) | 2023 pop. | Parcel viewer |
|---|---|---|---|---|
| Adams County | Hettinger | 988 | 2,163 | county web map |
| Bowman County | Bowman | 1,162 | 2,867 | county web map |
| Dickey County | Ellendale | 1,131 | 4,900 | North Dakota Parcel Viewer (NDGISHub) |
| Emmons County | Linton | 1,510 | 3,224 | ArcGIS Instant Apps |
| McIntosh County | Ashley | 975 | 2,488 | ArcGIS Web AppBuilder |
| Richland County | Wahpeton | 1,436 | 16,558 | county web map |
| Sargent County | Forman | 858 | 3,776 | ArcGIS Experience Builder |
| Sioux County | Fort Yates | 1,094 | 3,643 | ArcGIS Experience Builder |
South Dakota counties on the line
| County | Seat | Land (sq mi) | 2023 pop. | Parcel viewer |
|---|---|---|---|---|
| Brown County | Aberdeen | 1,713 | 37,733 | Beacon (Schneider Geospatial) |
| Campbell County | Mound City | 734 | 1,340 | planning-district WebGIS |
| Corson County | McIntosh | 2,470 | 3,782 | CAMAvision Maps |
| Harding County | Buffalo | 2,672 | 1,324 | CAMAvision Maps |
| Marshall County | Britton | 838 | 4,390 | planning-district WebGIS |
| McPherson County | Leola | 1,137 | 2,334 | planning-district WebGIS |
| Perkins County | Bison | 2,870 | 2,834 | CAMAvision Maps |
| Roberts County | Sisseton | 1,101 | 10,206 | planning-district WebGIS |
Which counties face each other
The Census adjacency file pairs counties that share a boundary. Use it to find the county across the line from the one you know:
- Adams County, ND borders Corson County, SD, Harding County, SD, Perkins County, SD
- Bowman County, ND borders Harding County, SD
- Dickey County, ND borders Brown County, SD, McPherson County, SD
- Emmons County, ND borders Campbell County, SD, Corson County, SD
- McIntosh County, ND borders Campbell County, SD, McPherson County, SD
- Richland County, ND borders Marshall County, SD, Roberts County, SD
- Sargent County, ND borders Brown County, SD, Marshall County, SD, Roberts County, SD
- Sioux County, ND borders Corson County, SD
What changes when you cross the line
- Different viewers. On the North Dakota side the official maps run on: county web map (3); ArcGIS Experience Builder (2); North Dakota Parcel Viewer (NDGISHub) (1); ArcGIS Instant Apps (1); ArcGIS Web AppBuilder (1). On the South Dakota side: planning-district WebGIS (4); CAMAvision Maps (3); Beacon (Schneider Geospatial) (1). Search boxes, parcel ID formats and the details shown in pop-ups will differ.
- Different records offices. Deeds, plats and tax bills are kept by the county where the parcel sits.
- Different rules. Zoning, septic permits and property tax are set locally and by each state, so check with the county on the side where you plan to build or buy.
Researching a tract that crosses the line
- Find the parcel in both counties' viewers. Each side will show only its own piece, with its own parcel number.
- Pull the recorded deed from each county's register or recorder, since each county records only the land inside its own boundary.
- Expect two tax bills, one from each county, and check each state's rules for homestead or farm exemptions.
- For a sale, a fence or a building permit, hire a licensed surveyor familiar with the line; tax-map lines are drawings, not surveys.
A quick way to check which side a spot is on
Search the address in the official parcel viewer of the county you expect (the links are in the tables above). If a county-run viewer shows no parcel at that spot, the land is probably in the neighboring county, so try that county's viewer next. Statewide viewers cover both sides, so check the county named in the parcel details.
Related guides
More: North Dakota counties · South Dakota counties
Sources
- U.S. Census Bureau county adjacency file, used for which counties share the line.
- U.S. Census Bureau Gazetteer files, 2020 county land area.
- U.S. Census Bureau, Population Estimates Program, county totals, Vintage 2023 (July 1, 2023 estimates)
- Platbookmapper county GIS directory (live data file behind our county pages, pulled October 21, 2026) for each county's official parcel viewer.
- County seats: Wikidata (county seat property), cross-checked against Census place names.