| Casey Key | |
| Settlement Type: | Island |
| Other Name: | Caseys Key, Treasure Island |
| Pushpin Map: | USA Florida |
| Pushpin Map Caption: | Location within the state of Florida |
| Subdivision Type: | Country |
| Subdivision Name: | United States |
| Subdivision Type1: | State |
| Subdivision Name1: | Florida |
| Subdivision Type2: | Counties |
| Subdivision Name2: | Sarasota |
| Established Title: | Established |
| Unit Pref: | Imperial |
| Population As Of: | 2010 |
| Population Density Km2: | auto |
| Timezone: | Eastern (EST) |
| Utc Offset: | −05:00 |
| Timezone Dst: | EDT |
| Utc Offset Dst: | −04:00 |
| Elevation Ft: | 13 |
| Postal Code Type: | ZIP codes |
| Area Code Type: | Area codes |
| Area Code: | 941 |
| Blank1 Name: | GNIS feature ID |
| Blank1 Info: | 280108[1] |
Casey Key is a barrier island off the coast of Southwest Florida, located south of Siesta Key. Casey Key is part of the North Port—Sarasota—Bradenton Metropolitan Statistical Area.
Casey Key is erroneously named after Captain John Charles Casey as a result of a United States Coast Survey chart published in 1851. Captain John Casey and his army were settled at Casey's Key, located south of the island, at the time.[2]