United States territorial acquisitions table


Following are the historical territorial acquisitions of the United States:
AccessionDateArea Area Cost in dollars
Original territory of the Thirteen States 1783892,1352,310,619-----
Annexation of the Vermont Republic17919,61624,905-----
Louisiana Purchase, from France1803827,9872,144,476$15,000,000
Florida Parishes, annexed from the Republic of West Florida, which took it from Spain in a filibusting expedition in 181018104,685.18412,134.57-----
Florida, purchased from Spain181972,101186,740$5,000,000
Texas annexation1845389,1661,007,935-----
Oregon Territory, by treaty with [United Kingdom of United Kingdom of Great Britain and Ireland|Great Britain and Ireland|Great Britain]1846286,541742,137-----
Mexican Cession, from Mexico1848529,1891,370,593$15,000,000
Gadsden Purchase, from Mexico185429,67076,845$10,000,000
Baker Island, unincorporated territory claimed under Guano Act of 185618570.51.29-----
Howland Island, unincorporated territory claimed under Guano Act of 185618570.61.55-----
Jarvis Island, unincorporated territory claimed under Guano Act of 185618571.74.4-----
Johnston Atoll, unincorporated territory claimed under Guano Act of 185618571.12.85-----
Alaska Purchase, from Russia1867591,0001,723,336$7,200,000
Midway Islands, annexation of unoccupied area186725.18-----
Annexation of the Republic of Hawaii18986,45016,705-----
Philippines, purchased from Spain 1898115,800299,921$20,000,000
Puerto Rico, by treaty with Spain18983,5089,085-----
Guam, by treaty with Spain1899209541-----
Eastern Samoa, by treaty with Great Britain and Germany189976197-----
Panama Canal Zone, by treaty with Panama19035531,432$10,000,000
Guantánamo, by treaty with Cuba190345116.5$3,386.25
Annexation of the Indian Territory190631,06980,468-----
Danish Virgin Islands, by purchase from Denmark1917136352$25,000,000
Kingman Reef, annexed19220.41.0-----
Swains Island, annexed19250.942.43-----
Kanton Island and Enderbury Island, joint occupation with Britain 19386.516.8-----
Water Island, by purchase from the East Asiatic Company, a private shipping company based in Denmark 19440.82.0$10,000
Mariana Islands, United Nations Trust Territory; self-governing as Northern Mariana Islands1947179467-----
Caroline Islands, United Nations Trust Territory; 1986 most islands adopt commonwealth status as Federated States of Micronesia19475001,295-----
Marshall Islands, United Nations Trust Territory; 1979 self-governing; 1986 independent as Republic of the Marshall Islands194770181-----

For information on internal territorial acquisitions, see List of U.S.–Native American treaties.