Largest Employers
| Company | # of Employees | Function |
| Fort Drum | 14,998 Soldiers 3,930 Civilian 820 Contractors |
Department of Defense |
| NYS ( Includes regional State offices & Correctional Facilities Located in Jefferson County located in Watertown & Cape Vincent | 1,921 | Government |
| Samaritan Medical Center & Samaritan Keep & Summit Senior Village 800 Washington St,Watertown, NY 13601 | 2453 | Healthcare |
| County of Jefferson | 790 | Government |
| Jefferson Rehabilitation Center PO Box 41 Watertown, NY 13601 |
557 | Healthcare |
| Jeff-Lewis BOCES 20104 NYS Route 3 Watertown, NY 13601 |
438 | Education |
| New York Air Brake Corp. 748 Starbuck Ave.Watertown, NY 13601 |
355 | Manufacturing |
| City of Watertown 245 Washington Street Watertown, NY 13601 |
397 | Government |
| Carthage Area Hospital 1001 West Street Carthage, NY 13619 |
384 | Healthcare |
| Jefferson Community College Coffeen Street Watertown, NY 13601 |
253 | Education |
| Watertown Family YMCA 119 Washington Street Watertown, NY 13601 |
239 | Recreation & Childcare |
| Johnson Newspaper Corp. 260 Washington Street Watertown, NY 13601 |
222 | Publishing |
| National Grid 21265 State Route 232 Watertown, NY 13601 |
207 | Utility |
| Timeless Frames PO Box 28 Watertown, NY 13601 |
47 | Manufacturing |
| HP HOOD, LLC PO Box 141 LaFargville, NY 13656 |
150 | Manufacturing |
| Purcell Construction 566 Coffeen Street Watertown, NY 13601 |
140 | Construction |
| River Hospital 4 Fuller Street Alexandria Bay, NY 13607 |
134 | Healthcare |
| Knowlton Technologies, LLC 213 Factory Street Watertown, NY 13601 |
143 | Manufacturing |
| Disabled Persons Action Organization (DPAO) | 125 | Healthcare |
| Fort Drum Mountain Community Homes PO Box 146 Black River, NY 13612 |
120 | Military Building Mgmt. |
| Great Lakes Cheese 23 Phelp St Adams, NY 13605 |
126 | Manufacturing |
| Hi-Lite Airfield Services Inc 18249 Hi-Lite Drive Adams Center, NY 13601 |
114 | Construction |
| The Stebbins Eng. & Mfg. Co. 363 Eastern Blvd. Watertown, NY 13601 |
110 | Manufacturing |
| Guilfoyle Ambulance Service PO Box 88 438 Newell Street Watertown, NY 13601 |
109 | Healthcare/Emergency Responders |
| Bernier Carr & Associates, 327 Mullin Street Watertown, NY 13601 |
107 | Engineering & Architecture |
| Renzi Brothers PO Box 23 Watertown, NY 13601 |
181 | Distribution |
| North Country Family Health Center 238 Arsenal Street Watertown, NY 13601 |
144 | Healthcare |
| Ox Industries 7798 N. State Street Lowville, NY 13367 |
81 | Manufacturing |
| Jain Irrigation ,Inc. 740 Water Street Watertown, NY 13601 |
97 | Manufacturing |
| Hilton Garden Inn & Holiday Inn Express & Suites 1290 Arsenal St. Watertown, NY 13601 |
89 | Hospitality |
| Cornell Cooperative Extension Association of Jefferson Co. 203 N. Hamilton Street Watertown, NY 13601 |
98 | Education (+ 30 Seasonal Employees) |
| Stature Electric Inc. PO Box 6660 Watertown, NY 13601 |
80 | Manufacturing |
| Slack Chemical PO Box 30 Carthage, NY 13619 |
80 | Distribution & Manufacturing |
| Thousand Islands Bridge Authority Collins Landng Alexandria Bay, NY 13607 |
66 | Transportation (+ 70 Seasonal employees) |
| Neenah Paper Bridge Street Brownville, NY 13615 |
70 | Manufacturing |
| Credo Comm. Center for Treatment of Addictions 595 West Main Street Watertown, NY 13601 |
69 | Healthcare |
| CEM Machine 571 West End Ave. Carthage, NY 13612 |
52 | Manufacturing |
| Jefferson Concrete 22850 Murrock Circle Watertown,NY13601 |
50 | Manufacturing |
| Current Applications 275 Bellew Ave. Watertown, NY 13601 |
60 | Manufacturing |
| Brookfield Power 800 Starbuck Ave. Watertown, NY 13601 |
41 | Utility |
