Terramuggus is a census-designated place (CDP) in the town of Marlborough, Hartford County, Connecticut, United States.

Connecticut Route 2 forms the northeastern edge of the CDP, with access at Exit 13 to Connecticut Route 66, which forms the southeastern edge of the CDP.

The racial makeup of the CDP was 98.00% White, 0.19% African American, 0.95% Asian, and 0.86% from two or more races.

17.7% of all households were made up of individuals, and 3.6% had someone living alone who was 65 years of age or older.

None of the families and 0.8% of the population were living below the poverty line, including no under eighteens and none of those over 64.