The North Jersey Coast Line is a commuter rail line traversing through the Jersey Shore region, running from Rahway to Bay Head. Operated by NJ Transit, the line is electrified as far south as Long Branch. On rail system maps it is colored light blue, and its symbol is a sailboat. The line runs along the former New York & Long Branch Railroad, which was co-owned by the Central Railroad of New Jersey and the Pennsylvania Railroad.

Most trains operate between New York Penn Station and Long Branch, with frequent rush-hour service and hourly local off-peak service. Diesel shuttle trains between Long Branch and Bay Head meet these electric trains, although a limited number of through trains operate during weekday rush hours between Bay Head and New York Penn Station, utilizing dual-mode engines. Hourly New York to Long Branch service operates on weekends, with bi-hourly diesel shuttle service (with some extra trains) between Long Branch and Bay Head. Full hourly service operates during the peak summer season. Some electric trains terminate at South Amboy and make all stops from New York Penn Station, providing local service for the Northeast Corridor stops of Rahway, Linden, Elizabeth, and North Elizabeth during rush hours.

The line is double tracked, except for the bridge over the Manasquan River at Brielle. The line has cab signals and wayside block signals; the line from Rahway to Long Branch is signaled for operation in either direction on both tracks (Northeast Operating Rules Advisory Committee Rule 261). Twelve interlockings facilitate flexibility in operation between the two tracks; these and other interlockings control movements to or from freight lines such as the Chemical Coast Secondary, the Amboy Secondary, and the Southern Secondary, as well as Long Branch Yard.

Passenger yards are at Long Branch and Bay Head. Long Branch Yard is fully electrified, and mostly interlocked. Bay Head contains a large balloon (circular looping) track where entire trains can reverse direction without backing up or uncoupling the locomotive, and obviating the need for a turntable. It remains in service, even though push-pull operation has eliminated the need for turning of trains. Bay Head Yard has no interlocking; all switches are hand-operated. A yard and sidings formerly existed at South Amboy, dating to when electrification ended there, but have since been removed; trains terminating at South Amboy cannot be bypassed by using the other track, as the new station has a single island platform.

Conrail Shared Assets Operations also operates over the North Jersey Coast Line to interchange with the Delaware and Raritan River Railroad in Red Bank.

The North Jersey Coast Line has five movable bridges of the twelve used by the NJT rail network, the most on any one line.

All these bridges were originally double-track spans, but Brielle Draw has been single-tracked since the mid-1970s. The line also crosses over several other waterways on fixed bridges, the longest of which is over the Navesink River at Red Bank.

The North Jersey Coast Line is electrified north of Long Branch.