Passadumkeag is a town on the east bank of the Penobscot River at the confluence with the Passadumkeag River in Penobscot County, Maine, United States.

[3] Passadumkeag is a word of the Penobscot people meaning "quick water".

2 Schoolhouse in Passadumkeag is listed on the National Register of Historic Places.

The racial makeup of the town was 95.5% White, 0.8% Native American, 0.5% Asian, and 3.2% from two or more races.

27.0% of all households were made up of individuals, and 11.3% had someone living alone who was 65 years of age or older.

The racial makeup of the town was 98.41% White, 0.45% Native American, 0.23% Pacific Islander, and 0.91% from two or more races.

21.5% of all households were made up of individuals, and 9.9% had someone living alone who was 65 years of age or older.