The Northeast Regional is an intercity rail service operated by Amtrak in the Northeastern and Mid-Atlantic United States. In the past it has been known as the NortheastDirect, Acela Regional, or Regional. It is Amtrak's busiest route, carrying 9,163,082 passengers in fiscal year (FY) 2023. The Northeast Regional service received more than $787.7 million in gross ticket revenue in FY 2023.

The Northeast Regional offers daily all-reserved service, usually at least every hour. Trains generally run along the Northeast Corridor between Boston in the north to Washington, D.C., in the south with multiple stops, including in New York City, Philadelphia, and Baltimore. Extensions and branches provide service to Newport News, Norfolk, and Roanoke, Virginia, and Springfield, Massachusetts, with intermediate stops.

Trains cover the most popular stretch between New York Penn Station and Washington Union Station in about 3.5 hours. The section between New York and Philadelphia takes 1.5 hours, while the part between Philadelphia and Washington takes two hours. North of New York, the travel time to Boston is four hours, while trips to Springfield take 3.5 hours. South of Washington, trains take 4.5 hours to reach Newport News, 4.5 hours to reach Norfolk, or five hours to reach Roanoke.

The services along the line, as inherited from Penn Central, once had their own names, such as the "Yankee Clipper" and the "Federal"; typically a name applied to at most one train and its "twin" in the opposite direction. Electrification ended at New Haven, Connecticut, requiring an engine change. On October 28, 1995, Amtrak introduced the "NortheastDirect" brand for all trains on the Northeast Corridor (and its extension to Newport News, Virginia) except for the express Metroliner and hourly Clocker services. The November 10, 1996, timetable restored the old names in addition to the NortheastDirect brand. The names (except the Twilight Shoreliner) were dropped with the May 16, 1999, schedule.

In 2000, Amtrak completed electrifying the route from New Haven to Boston in preparation for the introduction of the Acela Express, thereby eliminating the engine change at New Haven. The first two all-electric round-trips to and from Boston were branded Acela Regional and equipped with refurbished Amfleet cars painted in the Acela-like "Phase V" livery. All-electric service began on January 31, 2000. The NortheastDirect branding continued to be used for trains which changed from electric to diesel traction in New Haven.

Due to customer confusion with the Acela Express, the name was changed again on March 17, 2003, to simply "Regional." As part of rebranding and service improvements, the name was changed to "Northeast Regional" on June 23, 2008 (though it also appeared on schedules several months beforehand).

On May 12, 2015, Northeast Regional Train 188, traveling from Washington, D.C., to New York City, derailed in the Port Richmond neighborhood of Philadelphia, killing eight people and injuring more than 200 people. The train derailed along a curve and was determined to have been traveling at a speed of about 100 mph, exceeding the limit of 50 mph on that curve. This speed limit was not posted; engineers on that route are expected to rely on memory to control the speed of the train. Additionally, the train was suspected to have been hit by a projectile, as was a commuter train in the area shortly before the derailment.

Private sleeping rooms on overnight trains 65/66/67, last available in 2004 on the Federal, were made available effective April 5, 2021. The overnight trains were temporarily cancelled in January 2022; they resumed in July 2022 without sleepers. They were temporarily cancelled north of New York City effective April 4, 2023, due to Penn Station Access construction.

Some Northeast Regional trains continue into Virginia, serving three branches to Norfolk, Newport News, and Roanoke, serving points in between. These tracks are not electrified and are partially owned by both freight railroads and the State of Virginia.

Virginia and Amtrak partnered in 2009 under the brand Amtrak Virginia to expand passenger rail service within the Commonwealth, making Virginia the 15th state to fund state services in addition to federally funded routes.

One daily Northeast Regional round trip was extended to from Washington to Lynchburg via Manassas and Charlottesville on October 1, 2009, supplementing the existing Crescent service. Service was extended from Lynchburg to Roanoke starting October 31, 2017. A second daily Roanoke round trip was added on July 11, 2022. An extension from Roanoke to Christiansburg, Virginia, near Virginia Tech, is in planning, as is an infill station in Bedford, Virginia.

On July 20, 2010, Amtrak added an additional Northeast Regional frequency from Washington to Richmond Staples Mill Road station, increasing the Washington-Richmond corridor to eight daily round trips with hourly northbound morning service. One round trip was extended from Richmond to Norfolk starting December 12, 2012. A second daily Norfolk round trip on weekdays was added on March 4, 2019. One round trip was extended from Staples Mill to Main Street in September 2021. Service changes on July 11, 2022, added an additional Norfolk weekday round trip (making three round trips on weekdays and two on weekends).

In spring 2021, Amtrak proposed extending three Northeast Regional round trips from New York Penn Station to Ronkonkoma station along the Main Line of the Long Island Rail Road, with stops at Jamaica, Mineola, Hicksville, and Deer Park. The move would enable one-seat rides between Long Island and points south on the Northeast Corridor, provide express train service within Long Island, and connect JFK International Airport to the Amtrak network. In December 2023, the Federal Railroad Administration accepted the project into its Corridor Identification and Development Program, granting $500,000 toward service planning and prioritizing the route for future federal funding.

As of 2018, most Northeast Regional trains consist of 7 to 9 passenger cars hauled by a locomotive.

The passenger cars are the Amfleet I series passenger cars built by the Budd Company in the mid-to-late 1970s. Most trains include a Business Class car, a Café car (food service/lounge), and up to seven Coach Class cars, one of which is designated the Quiet Car, where passengers are asked to refrain from loud talking and mobile phone conversations.

Between Boston and Washington, the service has overhead electric wires and is pulled by Siemens ACS-64 electric locomotives at speeds up to 125 mph (201 km/h). Northeast Regional trains operating south of Washington, D.C., into Virginia, and on the New Haven–Springfield Line use GE Genesis diesel locomotives which have a slightly lower top speed of 110 mph (180 km/h).

In the coming years all equipment will be replaced with Amtrak Airo trainsets, the railroad's branding of its combination of Siemens Venture passenger cars and a Siemens Charger diesel-electric locomotive. The trainsets for the Northeast Corridor will have eight passenger cars, which will include a food service area and a mix of 2×2 Coach Class and 2×1 Business Class seating. The car closest to the locomotive will be a specialized "Auxiliary Power Vehicle" which will include a pantograph to collect power from overhead lines and will feed it to four traction motors in the car, and via a DC link cable, to the four traction motors in the locomotive. Outside of electrified territory, the locomotive's diesel engine will generate power for the traction motors. The arrangement will offer a near-seamless transition between power sources on through trains to Virginia and Springfield, Massachusetts, a process that currently requires a time-consuming locomotive change.

All classes of service include complimentary WiFi, an electric outlet (120 V, 60 Hz AC) at each seat, reading lamps, and fold-out tray tables. Reservations are required on all trains; tickets may be purchased online, over the phone, from a station agent, or via ticketing machine.

• Coach Class: 2×2 seating. Passengers self-select seats on a first-come, first-served basis.
• Business Class: 2×2 or 2×1 seating with more legroom than coach. Passengers receive a complimentary soft drink. Seats are assigned in advance.

Most Northeast Regional trains operate over the Northeast Corridor between Boston and Washington (via New York, Philadelphia, and Baltimore). The corridor is owned, in part, by Amtrak, the Massachusetts Bay Transportation Authority (MBTA), Metro-North Railroad (MNRR), and the Connecticut Department of Transportation (CDOT).

• MBTA Attleboro Line: Boston to MA/RI state line (dispatched and maintained by Amtrak)
• Amtrak Northeast Corridor: MA/RI state line to New Haven, Connecticut
• CDOT New Haven Line: New Haven to CT/NY state line (dispatched and maintained by MNRR)
• MNRR New Haven Line: CT/NY state line to New Rochelle, New York
• Amtrak Northeast Corridor: New Rochelle to Washington, D.C.

Some trips diverge at New Haven and turn north to serve Springfield, Massachusetts, operating over Amtrak's New Haven–Springfield Line. Additional service on that line is provided by Amtrak's Hartford Line trains, which have timed transfers to and from many Northeast Regional trips.

Several trips continue south of Washington D.C. to Virginia, running to either Roanoke, Richmond, Newport News, or Norfolk. All Virginia services use the northernmost portion of the ex-Richmond, Fredericksburg and Potomac Railroad (now owned by CSX Transportation) between Washington and Alexandria, Virginia. South of Alexandria, trains to Roanoke use the Norfolk Southern Railway (ex-Southern Railway, ex-Virginia Midland Railway). Trains to Richmond, Norfolk and Newport News use the CSX RF&P, Richmond Terminal, and Bellwood subdivisions between Alexandria and Richmond.

South of Richmond, trains to Newport News use the CSX Peninsula Subdivision (ex-Chesapeake and Ohio Railway). Trains to Norfolk use the CSX North End Subdivision and Norfolk Southern's Norfolk District (ex-Norfolk and Western Railway).

Amtrak receives federal funding for its operations between Boston and Washington, D.C. Northeast Regional operations south of Washington are funded in part by the Commonwealth of Virginia. Operations along the New Haven–Springfield Line are funded by the State of Connecticut and the Commonwealth of Massachusetts.

State	Town/City	Station	Connections
MA	Boston	South Station	Amtrak: Acela, Lake Shore Limited MBTA Commuter Rail: Fairmount Line, Framingham/Worcester Line, Franklin/Foxboro Line, Needham Line, Old Colony Lines, Greenbush Line, Providence/Stoughton Line MBTA subway:  Red Line   Silver Line  MBTA Bus Intercity bus service at South Station Bus Terminal
		Back Bay	Amtrak: Acela, Lake Shore Limited MBTA Commuter Rail: Framingham/Worcester Line, Franklin/Foxboro Line, Needham Line, Providence/Stoughton Line MBTA subway:  Orange Line  MBTA Bus
	Westwood	Route 128	Amtrak: Acela MBTA Commuter Rail: Providence/Stoughton Line
RI	Providence	Providence	Amtrak: Acela MBTA Commuter Rail: Providence/Stoughton Line Local bus: Rhode Island Public Transit Authority Amtrak Thruway
	West Kingston	Kingston	Local bus: Rhode Island Public Transit Authority
	Westerly	Westerly	Local bus: Rhode Island Public Transit Authority
CT	Mystic	Mystic	Local bus: Southeast Area Transit
	New London	New London	CTrail: Shore Line East Local bus: Southeast Area Transit Intercity bus: Greyhound
	Old Saybrook	Old Saybrook	CTrail: Shore Line East Local bus: Estuary Transit District
	New Haven	Union Station	Amtrak: Acela, Hartford Line, Vermonter CTrail: Hartford Line, Shore Line East Metro-North: ■ New Haven Line Local bus: CTtransit New Haven Intercity bus: Greyhound, Peter Pan
	Bridgeport	Bridgeport	Amtrak: Vermonter Metro-North: ■ New Haven Line, ■ Waterbury Branch Local bus: Greater Bridgeport Transit Authority
	Stamford	Stamford	Amtrak: Acela, Vermonter Metro-North: ■ New Haven Line, ■ New Canaan Branch, ■ Danbury Branch Local bus: CTtransit Stamford Intercity bus: Greyhound
NY	New Rochelle	New Rochelle	Metro-North: ■ New Haven Line Local bus: Bee-Line
	New York City	New York Penn Station	Amtrak (long-distance): Cardinal, Crescent, Lake Shore Limited, Palmetto, Silver Meteor Amtrak (intercity): Acela, Adirondack, Berkshire Flyer, Carolinian, Empire Service, Ethan Allen Express, Keystone Service, Maple Leaf, Pennsylvanian, Vermonter Long Island Rail Road: ■ Main Line, ■ Port Washington Branch NJ Transit: ■ North Jersey Coast Line, ■ Northeast Corridor Line, ■ Gladstone Branch, ■ Montclair-Boonton Line, ■ Morristown Line NYC Subway: ​​​​ PATH: HOB-33 JSQ-33 JSQ-33 (via HOB) Local bus: MTA Bus
NJ	Newark	Newark Penn Station	Amtrak: Acela, Cardinal, Carolinian, Crescent, Keystone Service, Palmetto, Pennsylvanian, Silver Meteor, Vermonter Newark Light Rail NJ Transit: ■ North Jersey Coast Line, ■ Northeast Corridor Line, ■ Raritan Valley Line PATH: NWK-WTC Local bus: NJ Transit Bus Intercity bus: Greyhound, Coach USA, Fullington Trailways
		Newark Airport	AirTrain Newark to Newark Liberty International Airport Amtrak: Keystone Service NJ Transit: ■ North Jersey Coast Line, ■ Northeast Corridor Line
	Iselin	Metropark	Amtrak: Acela, Crescent, Keystone Service, Palmetto, Vermonter NJ Transit: ■ Northeast Corridor Line Local bus: NJ Transit Bus
	New Brunswick	New Brunswick	Amtrak: Keystone Service NJ Transit: ■ Northeast Corridor Line Local bus: NJ Transit Bus Intercity bus: Suburban Transit
	West Windsor	Princeton Junction	Amtrak: Keystone Service NJ Transit: ■ Northeast Corridor Line, ■ Princeton Branch Local bus: NJ Transit Bus
	Trenton	Trenton	Amtrak: Cardinal, Carolinian, Crescent, Keystone Service, Palmetto, Pennsylvanian, Silver Meteor, Vermonter NJ Transit: ■ Northeast Corridor Line, ■ River Line SEPTA Regional Rail: ■ Trenton Line Local bus: SEPTA Suburban Bus, NJ Transit Bus
PA	Philadelphia	30th Street Station	Amtrak: Acela, Cardinal, Carolinian, Crescent, Keystone Service, Palmetto, Pennsylvanian, Silver Meteor, Vermonter SEPTA Regional Rail: all lines NJ Transit: ■ Atlantic City Line SEPTA Metro: Market–Frankford Line, Subway–Surface Trolleys Local bus: SEPTA City Bus, SEPTA Suburban Bus, NJ Transit Bus Intercity bus: Megabus, Martz Trailways
DE	Wilmington	Wilmington	Amtrak: Acela, Cardinal, Carolinian, Crescent, Palmetto, Silver Meteor, Vermonter SEPTA Regional Rail: ■ Wilmington/​Newark Line Local bus: DART First State Intercity bus: Greyhound
	Newark	Newark	SEPTA Regional Rail: ■ Wilmington/​Newark Line Local bus: Cecil Transit, DART First State, UNICITY Intercity bus: FlixBus
MD	Aberdeen	Aberdeen	MARC: ■ Penn Line Local bus: Harford Transit Intercity bus: Greyhound
	Baltimore	Penn Station	Amtrak: Acela, Cardinal, Carolinian, Crescent, Palmetto, Silver Meteor, Vermonter MARC: ■ Penn Line Light RailLink Local bus: MTA Maryland, Charm City Circulator
	Hanover	BWI Airport	Amtrak: Acela, Crescent, Vermonter MARC: ■ Penn Line Shuttle to Baltimore/Washington International Airport Local bus: MTA Maryland, UMBC Transit
	New Carrollton	New Carrollton	Amtrak: Vermonter MARC: ■ Penn Line Metro: Orange Line Local bus: Metrobus, TheBus, MTA Maryland Intercity bus: Greyhound
Washington, D.C.	Washington	Washington Union Station	Amtrak: Acela, Cardinal, Carolinian, Crescent, Floridian, Palmetto, Silver Meteor, Vermonter, Amtrak Thruway MARC: ■ Brunswick Line, ■ Camden Line, ■ Penn Line Virginia Railway Express: ■ Manassas Line, ■ Fredericksburg Line Metro: Red Line DC Streetcar: H Street/Benning Road Line Local bus: Metrobus, DC Circulator, MTA Maryland, Loudoun County Transit, PRTC Buses Intercity bus: Greyhound, Megabus, BestBus, Peter Pan, OurBus

State	Town/City	Station	Connections
MA	Springfield	Springfield	Amtrak: Lake Shore Limited, Hartford Line, Vermonter, Valley Flyer CTrail: Hartford Line Local bus: Pioneer Valley Transit Authority Intercity bus: Greyhound, Peter Pan
CT	Windsor Locks	Windsor Locks	Amtrak: Hartford Line, Vermonter, Valley Flyer CTrail: Hartford Line Local bus: CTtransit
	Windsor	Windsor	Amtrak: Hartford Line, Valley Flyer CTrail: Hartford Line Local bus: CTtransit
	Hartford	Hartford	Amtrak: Hartford Line, Vermonter, Valley Flyer CTrail: Hartford Line Local bus: CTtransit Hartford BRT: CTfastrak Intercity bus: Greyhound, Peter Pan
	Kensington	Berlin	Amtrak: Hartford Line, Valley Flyer CTrail: Hartford Line Local bus: CTtransit New Britain
	Meriden	Meriden	Amtrak: Hartford Line, Vermonter, Valley Flyer CTrail: Hartford Line Local bus: CTtransit Meriden
	Wallingford	Wallingford	Amtrak: Hartford Line, Valley Flyer CTrail: Hartford Line Local bus: CTtransit Wallingford
	New Haven	State Street	Amtrak: Hartford Line, Valley Flyer CTrail: Hartford Line, Shore Line East Metro-North: ■ New Haven Line Local bus: CTtransit New Haven
	To New Haven Union Station

State	Town/City	Station	Connections
DC	From Washington Union Station
VA	Alexandria	Alexandria	Amtrak: Cardinal, Carolinian, Crescent, Crescent, Floridian, Silver Meteor, Silver Star VRE: ■ Fredericksburg Line, ■ Manassas Line Metro:  Blue Line,  Yellow Line Local bus: Metrobus, DASH
	Woodbridge	Woodbridge	VRE: ■ Fredericksburg Line Local bus: OmniRide
	Quantico	Quantico	Amtrak: Carolinian VRE: ■ Fredericksburg Line Local bus: OmniRide
	Fredericksburg	Fredericksburg	Amtrak: Carolinian, Silver Meteor VRE: ■ Fredericksburg Line Local bus: FRED
	Ashland	Ashland
	Richmond	Richmond Staples Mill Road	Amtrak: Carolinian, Floridian, Palmetto, Silver Meteor, Thruway Motorcoach Local bus: Greater Richmond Transit Company
	Service to Newport News, Virginia
	Richmond	Richmond–Main Street	Local bus: Greater Richmond Transit Company
	Williamsburg	Williamsburg	Local bus: Hampton Roads Transit, Williamsburg Area Transit Authority
	Newport News	Newport News Transportation Center	Amtrak: Thruway Motorcoach Local bus: Hampton Roads Transit
	Service to Norfolk, Virginia
	Ettrick	Petersburg	Amtrak: Carolinian, Floridian, Palmetto, Silver Meteor
	Norfolk	Norfolk	Tide Light Rail Amtrak Thruway

State	Town/City	Station	Connections
Virginia	From Alexandria Union Station
	Burke	Burke Centre	VRE: ■ Manassas Line Local bus: Metrobus, Fairfax Connector
	Manassas	Manassas	Amtrak: Cardinal, Crescent VRE: ■ Manassas Line Local bus: OmniRide
	Culpeper	Culpeper	Amtrak: Cardinal, Crescent
	Charlottesville	Charlottesville	Amtrak: Cardinal, Crescent, Amtrak Thruway Local bus: Charlottesville Area Transit
	Lynchburg	Lynchburg	Amtrak: Crescent Local bus: Greater Lynchburg Transit Company
	Roanoke	Roanoke	Local bus: Valley Metro, SmartWay Amtrak Thruway

• Northeast Regional – Amtrak