After two miles (3.2 km), I-84 interchanges with I-380, with I-380 going southeast through the Pocono Mountains and I-84 continuing almost due east into Wayne and Pike counties.

This section of Pennsylvania is very lightly populated, and there are no major settlements on or near I-84, although it offers access to popular outdoor recreation areas such as Lake Wallenpaupack and Promised Land State Park.

Its right-of-way is very wide, with a large median strip between the two roadways as it passes through densely wooded country, except for the swampy areas in southern Wayne County.

The only development along Pennsylvania's section of I-84 is where US Route 6 (US 6) and US 209 start to parallel closely and form a commercial strip just south of Matamoras, just west of the Delaware River.

[3] I-84 enters New York by crossing both the Delaware and Neversink rivers on a long bridge south of Port Jervis, the first large settlement near the highway.

South of the road, at the confluence of the Delaware and Neversink rivers, is the Tri-States Monument, where New Jersey, New York, and Pennsylvania converge.

The New York State Department of Transportation (NYSDOT) completed the process of converting exits from sequential to mile-based numbering as part of a sign replacement project in 2021.

At exit 11, it turns to the northeast and descends to cross the Housatonic River on the Rochambeau Bridge, into New Haven County.

It then climbs onto higher ground to the city of Waterbury, which it passes on an elevated viaduct with the eastbound and westbound lanes on different levels.

[5] Though the route was confirmed in Connecticut, many issues remained in Rhode Island, the biggest of which were major environmental concerns about how the freeway would affect the Scituate Reservoir, which is the main drinking water supply for Providence.

Exit numbering on I-86 was that of the road's predecessor, Route 15, in a sequence beginning on New York's Hutchinson River Parkway.

It was transferred by NYSDOT to the New York State Thruway Authority (NYSTA) in order to capitalize on that agency's steady revenue stream from upstate sources.

In 1992, maintenance responsibility for I-84 in New York was transferred to the NYSTA and the monies for that purpose came from existing tolls on I-190 in downtown Buffalo, more than 300 miles (480 km) away.

On October 30, 2006, the NYSTA began the process of returning maintenance and operation responsibilities to NYSDOT and the tolls in Buffalo were discontinued.

This episode diminished local enthusiasm for a proposed $2-billion reconstruction of the "Mixmaster" interchange in downtown Waterbury between Route 8 and I-84.

[11] Former Connecticut Attorney-General Richard Blumenthal began a lawsuit against the contractor and an engineering firm in response to threats from USDOT to withhold funds from the project.