| Official Name: | Plattsville, Connecticut |
| Settlement Type: | Census-designated place |
| Pushpin Map: | Connecticut#USA |
| Pushpin Label: | Plattsville |
| Pushpin Label Position: | top |
| Coordinates: | 41.2247°N -73.2567°W |
| Subdivision Type: | Country |
| Subdivision Type1: | State |
| Subdivision Name1: | Connecticut |
| Subdivision Type2: | County |
| Subdivision Name2: | Fairfield |
| Subdivision Type3: | Towns |
| Subdivision Name3: | Easton, Fairfield |
| Area Footnotes: | [1] |
| Area Total Km2: | 2.58 |
| Area Land Km2: | 2.58 |
| Area Water Km2: | 0.0 |
| Population As Of: | 2020 |
| Timezone: | Eastern (EST) |
| Utc Offset: | -5 |
| Timezone Dst: | EDT |
| Utc Offset Dst: | -4 |
| Elevation Ft: | 200 |
| Postal Code Type: | ZIP Codes |
| Postal Code: | 06612 (Easton) 06825 (Fairfield) |
| Area Code: | 203/475 |
| Blank Name: | FIPS code |
| Blank Info: | 09-60365 |
| Blank1 Name: | GNIS feature ID |
| Blank1 Info: | 2805959 |
Plattsville is a census-designated place (CDP) in the towns of Easton and Fairfield, Fairfield County, Connecticut, United States. It is primarily in the town of Easton, with a portion extending south across the Mill River into Fairfield. The Merritt Parkway forms the southeast border of the CDP, and Connecticut Route 59 (Sport Hill Road in Easton and Easton Turnpike in Fairfield) runs north–south through it.
Plattsville was first listed as a CDP prior to the 2020 census.