Henry County, Missouri was organized December 13, 1834, as Rives County and later named after Patrick Henry. Clinton is the County Seat. The present county population is 21,997. The form of county government is township organization. Henry County is in the Western District of the Missouri Court of Appeals.
The principal towns, their population, zip codes and prefixes are:
| Town | Population | Zip Code | Telephone Prefix |
| Clinton (All -American City) | 9311 | 64735 | 885 and 890 |
| Windsor | 2990 | 65360 | 647 |
| Montrose | 417 | 64770 | 693 |
| Urich | 499 | 64788 | 638 |
| Deepwater | 507 | 64740 | 696 |
| Calhoun | 491 | 65323 | 694 |
[27th Circuit][Bates County][Henry County][St. Clair County]