New Jersey - Criteria: C (architecture/engineering)
| Jersey Homesteads Historic District |
| Johnsonburg Historic District |
| Johnson, William H., House |
| Jones, Benjamin, House |
| Jugtown Historic District |
| Kay-Evans Farm |
| Kearney, Edward S., House |
| Kelly, Eugene V., Carriage House |
| Kennedy House and Mill |
| Kennedy-Martin-Stelle Farmstead |
| Keuffel and Esser Manufacturing Complex |
| Kingsland Manor |
| Kingston Mill Historic District |
| Kingston Village Historic District |
| Kip Homestead |
| Kirby's Mill |
| Kirch-Ford House |
| Kline Farmhouse |
| Kossuth Street School |
| Krueger Mansion |
| Kuser, Rudolph V., Estate |
| Labor Bank Building |
| Ladd's Castle |
| Lafayette Village Historic District |
| Lake Hopatcong Yacht Club |
| Lambertville Historic District |
| Lambertville House |
| Lamington Historic District |
| Lander-Stewart Mansion and Stites Building |
| Landis Theatre-Mori Brothers Building |
| Lansdown |
| Lawrence Mansion |
| Lawrence Township Historic District |
| Lawson, James and Mary, House |
| Layton, Richard, House |
| Leaming, Thomas, House |
| Lebanon Historic District |
| Ledgewood Historic District |
| Leigh, Ichabod, House |
| Lembeck and Betz Eagle Brewing Company District |
| Liberty Corner Historic District |
| Lincoln Park Historic District |
| Lindenwold |
| Linn, Alexander and James, Homestead |
| Linwood Borough School No. 1 |
| Linwood Historic District |
| Littel-Lord Farmstead |
| Little Egg Harbor Friends Meeting House |
| Little Red Schoolhouse |
| Little Silver Station |
| Little York Historic District |
| Livingston Avenue Historic District |
| Livingston Homestead |
| Livingston Manor Historic District |
| Locktown Baptist Church |
| Log Cabin and Farm |
| Longstreet Farm |
| Low, Effingham, House |
| Lucy, the Margate Elephant |
| Ludlam, Henry, House |
| Ludlam, Thomas Jr., House |
| Lydecker, Garret, House |
| Lyons Station |
| Lyons Veterans Administration Hospital Historic District |
| MacGregor-Tallman House |
| Maddock's, Thomas, Sons Company |
| Madison Civic Commercial District |
| Madison Hotel |
| Madison Masonic Lodge |
| Madison Public Library and the James Building |
| Madison Station |
| Main Post Office |
| Main Street Friends Meeting House |
| Maloney, Martin, Cottage |
| Manahawkin Baptist Church |
| Manitou Park School House |
| Mansion House |
| Maplewood |
| Maplewood Municipal Building |
| Marcouse Building |
| Marine National Bank |
| Market Street Historic District |
| Marsellis House |
| Marshall, James W., House |
| Marshalltown Historic District |
| Marven Gardens Historic District |
| Masker House |
| Matawan Station |
| Maurice River Lighthouse |
| Mauricetown Historic District |
| Mays Landing Historic District |
| Mays Landing Presbyterian Church |
| Maywood Railroad Station |
| McDonald's-Kline's Mill |
| McKinney, David, Mill |
| McLeod-Rice House |
| Meadowburn Farm |
| Meadows, The |
| Mechlins Corner Tavern |
| Mecum, William and Margaret, House |
Data from United States Park Service and Wikidata