I-393 then ends, and US-4/US-202 merge onto Route 9 eastbound through Chichester and into Epsom. routes overlap I-393 to its terminus in the northern corner of Pembroke.

Route 202 which run eastbound out of the city. At this interchange, US-4 leaves I-93 and joins Interstate 393 and U.S. US-4 joins I-93 southbound, and runs along the freeway until Exit 15E in Concord. US-3 and US-4 share a short concurrency (about a mile), before US-4 turns east to interchange with Interstate 93 at Exit 17. US-4 enters the town of Salisbury and crosses Route 127, before continuing into Boscawen and intersecting with U.S. US-4 and Route 11 run concurrently through Andover for about 2 miles (3.2 km) before splitting, Route 11 to the northeast and US-4 to the southeast.

In Andover, US-4 turns back to the east and meets Route 11 near Route 4A's eastern terminus. The road turns to the south at this point, passing through Grafton and Danbury, where US-4 meets the west end of Route 104 and continues south into Andover. US-4 continues east through Enfield and into Canaan, where it meets the southern end of Route 118. US-4 continues east away from the freeway near Mascoma Lake, where Route 4A splits off to the southeast.

The road crosses Route 120, continues east and interchanges with I-89/Route 10 again. At this point, Route 10 joins the I-89 freeway southbound, while US-4 continues east into downtown Lebanon. US-4 turns south onto Route 10, and the two routes turn south, meeting Route 12A before turning towards and interchanging with Interstate 89. Route 4 crosses the Connecticut River into New Hampshire in the community of West Lebanon, where it immediately intersects Route 10 which runs parallel to the river.

Enroute 4 index