I-290 enters Marlborough with an exit for the Solomon Pond Mall and has its final junction with I-495, where it becomes the Route 85 Connector, which continues into Hudson.

Additionally, I-290 was intended to be extended past I-495 to I-95/Route 128 in Waltham, but this was canceled under pressure from towns along the planned route.

The interchange with I-495 was originally supposed to be a cloverleaf, but, after the plan was canceled, it was modified with a flyover ramp onto I-495 northbound.

On July 29, 2021, MassDOT announced that the exit renumbering on I-395 and I-290 will start on August 8, and it lasted for two weeks.

[5] The department had stated that it would consider redesignating I-290 as an extension of I-395 if both the exit numbering project and dual mile markers are well-received by motorists.