Route 289 was originally part of Route 89, a highway designated in 1932 leading from Lebanon to Union via Willimantic. Route 195 was a short highway leading from Route 89 in Mansfield Center to US 44 north of Storrs.

In 1935, today's Route 289 was also known as the Beaumont Memorial Highway.

On Dec. 1, 1964, the state extended Route 195 south to US 6 in Willimantic, replacing part of Route 89. This was done possibly to help motorists find their way to the University of Connecticut using a single route number. The leftover portion of old Route 89 south of Willimantic became Route 289.

In Lebanon, south of Burnham Road, a small side road on Route 289 is still called "Old Route 89".

In 1971, the state proposed an improvement to 0.7 miles of Route 289 in Windham, leading from the Lebanon town line to Hayden Street. This might have been implemented.