The National Wilderness Preservation System includes 806 wilderness areas protecting 111,889,002 acres (174,826.566 sq mi; 452,798.73 km²) of federal land as of 2023^[update]. They are managed by four agencies:

• National Park Service (NPS)
• United States Forest Service (USFS)
• United States Fish and Wildlife Service (FWS)
• Bureau of Land Management (BLM)

These wilderness areas cover about 4.5% of the United States' land area, an area larger than the state of California. About 52% of the wilderness area is in Alaska, with 57,425,569 acres (89,727.452 sq mi; 232,393.03 km²) of wilderness. They are located in 44 states (excepting Connecticut, Delaware, Iowa, Kansas, Maryland, and Rhode Island) and Puerto Rico.

The NPS has oversight of 43,890,500 acres (68,578.9 sq mi; 177,619 km²) of wilderness at 61 locations. The USFS oversees 36,160,078 acres (56,500.122 sq mi; 146,334.64 km²) of wilderness areas in 447 areas. The FWS has responsibility for 20,702,350 acres (32,347.42 sq mi; 83,779.4 km²) in 71 areas. BLM oversees 8,726,011 acres (13,634.392 sq mi; 35,312.91 km²) at 224 sites. Some wilderness areas are managed by multiple agencies.

Some areas are designated wilderness by state or tribal governments. These are not governed by the Federal National Wilderness Preservation System.

This table lists all U.S. areas that have been designated by the United States Congress under the Wilderness Act. The designation date is the date that the wilderness was signed into law. Some areas have been expanded or otherwise changed since their original designation.