The United States expanded from 13 to 50 states over 172 years. Here is the chronological order of admission:
| State | Admission Date |
|---|---|
| Delaware | Dec 7, 1787 |
| Pennsylvania | Dec 12, 1787 |
| New Jersey | Dec 18, 1787 |
| Georgia | Jan 2, 1788 |
| Connecticut | Jan 9, 1788 |
| Massachusetts | Feb 6, 1788 |
| Maryland | Apr 28, 1788 |
| South Carolina | May 23, 1788 |
| New Hampshire | Jun 21, 1788 |
| Virginia | Jun 25, 1788 |
| New York | Jul 26, 1788 |
| North Carolina | Nov 21, 1789 |
| Rhode Island | May 29, 1790 |
| Vermont | Mar 4, 1791 |
| Kentucky | Jun 1, 1792 |
| Tennessee | Jun 1, 1796 |
| Ohio | Mar 1, 1803 |
| Louisiana | Apr 30, 1812 |
| Indiana | Dec 11, 1816 |
| Mississippi | Dec 10, 1817 |
| Illinois | Dec 3, 1818 |
| Alabama | Dec 14, 1819 |
| Maine | Mar 15, 1820 |
| Missouri | Aug 10, 1821 |
| Arkansas | Jun 15, 1836 |
| Michigan | Jan 26, 1837 |
| Florida | Mar 3, 1845 |
| Texas | Dec 29, 1845 |
| Iowa | Dec 28, 1846 |
| Wisconsin | May 29, 1848 |
| California | Sep 9, 1850 |
| Minnesota | May 11, 1858 |
| Oregon | Feb 14, 1859 |
| Kansas | Jan 29, 1861 |
| West Virginia | Jun 20, 1863 |
| Nevada | Oct 31, 1864 |
| Nebraska | Mar 1, 1867 |
| Colorado | Aug 1, 1876 |
| North Dakota | Nov 2, 1889 |
| South Dakota | Nov 2, 1889 |
| Montana | Nov 8, 1889 |
| Washington | Nov 11, 1889 |
| Idaho | Jul 3, 1890 |
| Wyoming | Jul 10, 1890 |
| Utah | Jan 4, 1896 |
| Oklahoma | Nov 16, 1907 |
| New Mexico | Jan 6, 1912 |
| Arizona | Feb 14, 1912 |
| Alaska | Jan 3, 1959 |
| Hawaii | Aug 21, 1959 |