Illinois - Criteria: B (person)
| Lake-Peterson House |
| Larchmound |
| Lathrop, Bryan, House |
| Lebanon Historic District |
| Lewis, John L., House |
| Lewis, John W., House |
| Library Hall |
| Lillie, Frank R., House |
| Lincoln Home National Historic Site |
| Lincoln's New Salem Village |
| Lincoln Tomb |
| Lindsay, Vachel, House |
| Little Brick House |
| Lloyd, Henry Demarest, House |
| Lovejoy, Owen, Homestead |
| Macktown Historic District |
| Main Street Historic District |
| Mark, Caroline, House |
| Marshall, John, House Site |
| Marsh, William W., House |
| Maverick Lloyd, Lola, House |
| Mazon Creek Fossil Beds |
| McWorter, Free Frank, Grave Site |
| Menard, Pierre, House |
| Mermaid House Hotel |
| Mershon, Joab, House |
| Metal Shop |
| Metamora Courthouse |
| Military Drill Hall and Men's Gymnasium |
| Milk, Lemuel, Carriage House |
| Miller-Davis Law Buildings |
| Miller, George H., House |
| Miller, Joseph, House |
| Millikan, Robert A., House |
| Millikin, James, House |
| Milne, Robert, House |
| Moore, C. H., House |
| Morgan-Wells House |
| Mount Lookout |
| Muller House |
| Naples Mound 8 |
| Natural History Building |
| Nauvoo Historic District |
| Newcomb, Richard F., House |
| Noble-Seymour-Crippen House |
| Old Main, Knox College |
| Old State Capitol |
| Orchestra Hall |
| Oughton, John R., House |
| Paine House |
| Peabody, Francis Stuyvesant, House |
| Pennsylvania Avenue Historic District |
| Perkins, Dwight, House |
| Phelps, Alexis, House |
| Pine Craig |
| Post House |
| Potter House |
| Power Farmstead |
| Price-Prather House |
| Princeton Chapter House |
| Public Service Building |
| Quinby, Ivory, House |
| Railway Exchange Building |
| Rainey, Henry T., Farm |
| Ratcliff Inn |
| Reagan's, Ronald, Boyhood Home |
| Red Bud Historic District |
| Reorganized Church of Jesus Christ of Latter Day Saints |
| Ricker, Nathan C., House |
| Robinson-Stewart House |
| Roche, Martin-John Tait House |
| Rock Island Arsenal |
| Rockton Historic District |
| Rogers, Orson, House |
| Rohrbough, Calendar, House |
| Ross, Harvey Lee, House |
| Rutherford, Dr. Hiram, House and Office |
| Schulze Baking Company Plant |
| Sears, Albert H., House |
| Shelbyville Historic District |
| Shiloh House |
| Smith, J. P., Shoe Company Plant |
| Spafford, Amos Catlin, House |
| S.R. Crown Hall |
| Stacy's Tavern |
| State Savings Loan and Trust |
| Stephenson, Benjamin, House |
| Stevenson, Adlai E., I, House |
| Stevenson, Adlai E., II, Farm |
| Stevenson House |
| Steward, Lewis, House |
| Stickney, George, House |
| Stolp Woolen Mill Store |
| Swift House |
| Table Grove Community Church |
| Taft Farmstead |
| Taft, Lorado, Midway Studios |
| Taylor, Oscar, House |
| Terwilliger House |
| Theurer-Wrigley House |
Data from United States Park Service and Wikidata
