| Amboy District No. 2 Schoolhouse | East Amboy | Building | 2020 |
| Ames, Leonard, Farmhouse | Mexico | Building | 1991 |
| Ames, Orson, House | Mexico | Building | 2001 |
| Arthur Tavern | Arthur | Building | 1991 |
| Barlow, Smith H., House | Lacona | Building | 1988 |
| Brosemer Brewery | Oswego | Building | 2010 |
| Buckhout-Jones Building | Oswego | Building | 2001 |
| Carley's Mills Schoolhouse | Hastings | Building | 2005 |
| CHANCELLOR (tugboat) | Fulton | Structure | 2000 |
| Chandler, Peter, House | Mexico | Building | 1991 |
| Clark, Starr, Tin Shop | Mexico | Building | 2001 |
| Clarke, Edwin W. and Charlotte, House | Oswego | Building | 2002 |
| Davis, Phineas, Farmstead | Mexico | District | 1991 |
| Derrick Boat No. 8 | Oswego | Structure | 2015 |
| Edwards, John B. and Lydia, House | Oswego | Building | 2001 |
| First Baptist Church | Sandy Creek | Building | 1988 |
| First Congregational Church and Society of Volney | Volney | Building | 2001 |
| First National Bank of Lacona | Lacona | Building | 1988 |
| Fort Brewerton | Brewerton | Site | 1973 |
| Fort Ontario | Oswego | District | 1970 |
| Fowler-Loomis House | Mexico | Building | 1991 |
| Franklin Square Historic District | Oswego | District | 1982 |
| Fulton Public library | Fulton | Building | 1999 |
| Green, Nathan and Clarissa, House | Oswego | Building | 2002 |
| Hamilton Farmstead | Mexico | District | 1991 |
| Holyoke Cottage | Sandy Creek | Building | 1988 |
| Hunter-Oliphant Block | Oswego | Building | 1995 |
| Kingsford Historic District | Oswego | District | 2014 |
| Kingsford House | Oswego | Building | 1997 |
| Lacona Clock Tower | Lacona | Structure | 1988 |
| Lacona Railroad Station and Depot | Lacona | Building | 2002 |
| Littlefield, Hamilton and Rhoda, House | Oswego | Building | 2002 |
| Market House | Oswego | Building | 1974 |
| McKenzie, John and Harriet, House | Oswego | Building | 2001 |
| Methodist Church | Sandy Creek | Building | 1988 |
| Mexico Academy and Central School | Mexico | Building | 1991 |
| Mexico Octagon Barn | Mexico | Building | 1991 |
| Mexico Railroad Depot | Mexico | Building | 1991 |
| Mexico Stone Store, The | Mexico | Building | 2010 |
| Mexico Village Historic District | Mexico | District | 1991 |
| Montcalm Park Historic District | Oswego | District | 2001 |
| Mount Adnah Cemetery | Fulton | Site | 2001 |
| Northrup-Gilbert House | Phoenix | Building | 2000 |
| Oak Street School | Fulton | Building | 2003 |
| Oswego and Syracuse Railroad Freight House | Oswego | Building | 2017 |
| Oswego Armory | Oswego | Building | 1988 |
| Oswego City Hall | Oswego | Building | 1973 |
| Oswego City Library | Oswego | Building | 1971 |
| Oswego County Courthouse | Oswego | Building | 2000 |
| Oswego Theater | Oswego | Building | 1988 |
| Oswego West Pierhead Lighthouse | Oswego | Building | 2000 |
| Oswego Yacht Club | Oswego | Building | 2010 |
| Pease, Daniel and Miriam, House | Oswego | Building | 2002 |
| Pitt, Newton M., House | Sandy Creek | Building | 1988 |
| Pleasant Lawn Cemetery | Parish | Site | 2005 |
| Pontiac Hotel | Oswego | Building | 1983 |
| Pratt, John Wells, House | Fulton | Building | 1999 |
| Pulaski Village Historic District | Pulaski | District | 1983 |
| Red Mill Farm | Colosse | District | 1991 |
| Richardson-Bates House | Oswego | Building | 1975 |
| Riverside Cemetery | Oswego | District | 1993 |
| Sadler, Samuel, House | Sandy Creek | Building | 1988 |
| Salisbury, Charles, M., House | Lacona | Building | 1988 |
| Sandy Creek Historic District | Sandy Creek | District | 1988 |
| Schroeppel House | Schroeppel | Building | 1982 |
| Selkirk Lighthouse | Pulaski | Structure | 1979 |
| Sheldon Hall | Oswego | Building | 1980 |
| Shoecraft, Matthew, House | Lacona | Building | 1988 |
| Skinner, Timothy, House | Mexico | Building | 1991 |
| Slack Farmstead | Mexico | District | 1991 |
| Sloan, George B., Estate | Oswego | Building | 1988 |
| Smart, Fred, House | Lacona | Building | 1988 |
| St. James' Church | Cleveland | Building | 1996 |
| St. John's Episcopal Church | Phoenix | Building | 1993 |
| Standard Yarn Company Building | Oswego | Building | 2008 |
| State Street Methodist Episcopal Church | Fulton | Building | 2013 |
| Stillman Farmstead | Mexico | District | 1991 |
| Stillwater Bridge | Stillwater | Structure | 1997 |
| Sweet Memorial Building | Phoenix | Building | 1990 |
| Tanner Block | Oswego | Building | 2010 |
| Thayer Farmstead | Mexico | District | 1991 |
| Trinity Church | Constantia | Building | 1982 |
| Tuttle, Newman, House | Lacona | Building | 1988 |
| U.S. Customhouse | Oswego | Building | 1976 |
| US Post Office-Fulton | Fulton | Building | 1989 |
| Van Buren, David, House | Fulton | Building | 1988 |
| Van Buren, John, Tavern | Fulton | Building | 1988 |
| Van Buren, Volkert, House | Fulton | Building | 1988 |
| Walton and Willett Stone Store | Oswego | Building | 1976 |
| Washington Square Historic District | Oswego | District | 2010 |
| West Broadway Commercial Historic District | Fulton | District | 2020 |
| Wing, Asa and Caroline, House | Mexico | Building | 2001 |
| Woodruff Block | Oswego | Building | 1995 |
Ames, Leonard, Farmhouse Mexico · Building · listed 1991 
Arthur Tavern Arthur · Building · listed 1991 
Carley's Mills Schoolhouse Hastings · Building · listed 2005 
CHANCELLOR (tugboat) Fulton · Structure · listed 2000 
Chandler, Peter, House Mexico · Building · listed 1991 
First Baptist Church Sandy Creek · Building · listed 1988 
First National Bank of Lacona Lacona · Building · listed 1988 
Fort Ontario Oswego · District · listed 1970 
Fowler-Loomis House Mexico · Building · listed 1991 
Hamilton Farmstead Mexico · District · listed 1991