Millis is a town in Norfolk County in the U.S. state of Massachusetts. It had a population of 8,460 at the 2020 census. It contains the census-designated place of Millis-Clicquot. The town is approximately 19 miles southwest of downtown Boston and is bordered by Norfolk, Sherborn, Holliston, Medfield, and Medway. Massachusetts state routes 109 an…Millis is a town in Norfolk County in the U.S. state of Massachusetts. It had a population of 8,460 at the 2020 census. It contains the census-designated place of Millis-Clicquot. The town is approximately 19 miles southwest of downtown Boston and is bordered by Norfolk, Sherborn, Holliston, Medfield, and Medway. Massachusetts state routes 109 and 115 run through Millis.