St. Lawrence County, New York

County seat: Canton · Population 105,488 (2025) · 2,680 sq mi

St. Lawrence County is the 27th most populous of New York's 62 counties, with 105,488 people (2025 estimate). Its county seat is Canton. The map shows its 11 cities and towns and the 5 neighboring counties.

Map of St. Lawrence County, New York with cities, towns and the county boundary
St. Lawrence County, New York with its cities and towns, unincorporated communities (CDPs) and neighboring counties. Boundaries: U.S. Census Bureau, 2025. Free to use with attribution (CC BY 4.0).
Download PDF (Letter) 107 KBPNG image 91 KBNew York county map

St. Lawrence County facts

County seat
Canton
Population (2025 estimate)
105,488 −2.8% since 2020
Land area
2,680 sq mi 1st largest of 62
Water area
142 sq mi
Population density
39 per sq mi
Established
1802
Named after
St. Lawrence River major river in eastern Canada and the United States, flowing into the Gulf of St. Lawrence
Largest city
Potsdam 14,367
Median household income
$62,850
Cities and towns
11 plus 15 CDPs
ZIP codes
54
Time zone
Eastern
FIPS code
36089

Cities and towns in St. Lawrence County

St. Lawrence County has 11 incorporated cities, towns and villages. Populations count the people living inside St. Lawrence County; cities that cross a county line also list the other counties.

NameTypePopulation 2025Also in
MassenaVillage9,898
OgdensburgCity9,123
PotsdamVillage8,019
Canton (county seat)Village6,894
GouverneurVillage3,560
NorwoodVillage1,521
WaddingtonVillage925
HeuveltonVillage706
Rensselaer FallsVillage318
HammondVillage281
RichvilleVillage257

Unincorporated communities (CDPs)

Census-designated places are communities without their own city government; the county provides their services.

CommunityPopulationAlso in
Norfolk1,204
Brasher Falls776
Hannawa Falls744
Star Lake713
Madrid641
Hermon636
Parishville634
Hailesboro583
Winthrop530
DeKalb Junction511
Edwards490
Morristown384
Colton260
Akwesasne256Franklin County
Cranberry Lake219

ZIP codes in St. Lawrence County

54 ZIP codes reach into St. Lawrence County. ZIP codes ignore county lines, so some also cover a neighboring county.

Population of St. Lawrence County, 2020–2025

St. Lawrence County shrank by 3,017 people (−2.8%) between April 2020 and July 2025: 1,122 more deaths than births and a net loss of 1,836 people from migration.

Year (July 1)Population
2020108,182
2021107,563
2022106,900
2023106,607
2024106,168
2025105,488

Neighboring counties

Printable St. Lawrence County map

The PDF is a vector file with real text: it prints sharp on Letter paper and you can search it for a town. The PNG is 2400 pixels wide for slides and documents. Both are free to use with a credit to WhichCounty.

Paste this code to embed the map on your site:

Sources

Back to the New York county map with all 62 counties. Found an error? Tell us.