| Official Name: | Old Mystic, Connecticut |
| Settlement Type: | Census-designated place |
| Location: | Long Island Sound |
| Subdivision Type: | Country |
| Subdivision Name: | United States |
| Subdivision Type1: | State |
| Subdivision Name1: | Connecticut |
| Subdivision Type2: | County |
| Subdivision Name2: | New London |
| Subdivision Type3: | Town |
| Subdivision Name3: | Groton |
| Unit Pref: | Imperial |
| Area Total Km2: | 11 |
| Area Land Km2: | 11 |
| Area Water Km2: | 0.26 |
| Area Total Sq Mi: | 4.4 |
| Area Land Sq Mi: | 4.3 |
| Area Water Sq Mi: | 0.1 |
| Population As Of: | 2010 |
| Population Total: | 3554 |
| Population Density Km2: | auto |
| Timezone: | Eastern (EST) |
| Utc Offset: | −5 |
| Timezone Dst: | EDT |
| Utc Offset Dst: | −4 |
| Elevation M: | 42 |
| Elevation Ft: | 138 |
| Postal Code Type: | ZIP code |
| Postal Code: | 06355 |
| Area Code: | 860 |
| Blank Name: | FIPS code |
| Blank Info: | 09-57180 |
| Blank1 Name: | GNIS feature ID |
| Blank1 Info: | 2377846 |
Old Mystic is a village[1] and census-designated place (CDP) located in the town of Groton, Connecticut. The population was 3,554 at the 2010 census.[2]
According to the United States Census Bureau, the CDP has a total area of 4.4sqmi, of which 4.3sqmi is land and 0.1sqmi, or 2.29%, is water.
As of the census[3] of 2000, there were 3,205 people, 1,205 households, and 880 families residing in the CDP. The population density was 750.5sp=usNaNsp=us. There were 1,249 housing units at an average density of 292.5sp=usNaNsp=us. The racial makeup of the CDP was 90.11% White, 2.43% African American, 0.66% American Indian, 3.43% Asian, 0.06% Pacific Islander, 0.50% from other races, and 2.81% from two or more races. Hispanic or Latino of any race were 1.62% of the population.
There were 1,205 households, out of which 34.6% had children under the age of 18 living with them, 60.0% were married couples living together, 9.4% had a female householder with no husband present, and 26.9% were non-families. 19.5% of all households were made up of individuals, and 5.1% had someone living alone who was 65 years of age or older. The average household size was 2.64 and the average family size was 3.06.
In the CDP, the population was spread out, with 25.7% under the age of 18, 5.5% from 18 to 24, 32.7% from 25 to 44, 25.3% from 45 to 64, and 10.7% who were 65 years of age or older. The median age was 38 years. For every 100 females, there were 96.1 males. For every 100 females age 18 and over, there were 97.2 males.
The median income for a household in the CDP was $63,036, and the median income for a family was $68,500. Males had a median income of $50,095 versus $31,536 for females. The per capita income for the CDP was $27,988. About 1.5% of families and 3.2% of the population were below the poverty line, including 1.6% of those under age 18 and 3.8% of those age 65 or over.
The census-designated place, along with the rest of Groton Town, is in the Groton School District.[4]