The Acela ( ; originally the Acela Express until September 2019) is Amtrak's flagship passenger train service along the Northeast Corridor (NEC) in the Northeastern United States between Washington, D.C., and Boston via 13 intermediate stops, including Baltimore, Philadelphia, New York City, and Providence. Acela trains are the fastest in the Americas, with a top speed of , qualifying as high-speed rail, but only for about of the route.
In fiscal year 2025, Acela carried more than 3.1 million passengers, second only to the slower and less expensive Northeast Regional, which had over 12 million passengers. Ridership was down from the pre-COVID-19 pandemic high of 3,557,455 passengers in 2019. Its 2025 revenue of $570 million was around 20.6% of Amtrak's total.
Acela operates along routes that are used by slower regional passenger traffic, and only reaches the maximum allowed speed of the tracks along some sections, with the fastest peak speed along segments between Mansfield, Massachusetts, and Richmond, Rhode Island, as well as between South Brunswick and Trenton, New Jersey. Acela trains use active tilting technology, which helps control lateral centrifugal force, allowing the train to travel at higher speeds on the sharply curved NEC without disturbing passengers. The high-speed operation occurs mostly along the route from Pennsylvania Station in New York City to Union Station in Washington, D.C., with a fastest scheduled time of 2 hours and 45 minutes and an average speed of , including time spent at intermediate stops.The timetable gives 2 hours and 45 minutes, minimum, between Washington and New York. Dividing that into the distance traveled, , gives an average speed of . Over this route, Acela and the Northeast Regional service captured an 83% share of air/train commuters between New York and Washington in 2021, up from 37% in 2000.
The Acela speed is limited by traffic and infrastructure on the route's northern half. On the section from Boston's South Station to New York's Penn Station, the fastest scheduled time is 3 hours and 30 minutes, or an average speed of .The timetable gives 3 hours and 30 minutes, minimum, between New York and Boston. Dividing that into gives an average speed of . Along this section, Acela has captured a 54% share of the combined train and air market. The entire route from Boston to Washington takes between 6 hours, 38 minutes and 6 hours, 50 minutes, at an average speed of around .The timetable gives 6 hours and 30 minutes, minimum, between Washington and Boston. Dividing that into gives an average speed of .
In 2025, the original Acela Express equipment began to be replaced by new Avelia Liberty trainsets, which Amtrak markets as the NextGen Acela. The new trains have greater passenger capacity and an enhanced active tilt system that allows higher speeds on the many curved sections of the route. The first five trainsets entered passenger service on August 28, 2025, and as of August 2026, 16 of the total order of 28 trainsets have entered service.
History Background Following the success of Japan's newly inaugurated Shinkansen network in the 1960s, the High Speed Ground Transportation Act of 1965 authorized the U.S. government to explore the creation of high-speed rail, which resulted in the introduction of the higher-speed Metroliner trains between Washington, D.C., and New York City in 1969, the predecessor to Acela. During the 1980s, the U.S. Federal Railroad Administration explored the possibilities of high-speed rail in the United States. On December 18, 1991, five potential high speed rail corridors were authorized, including the Northeast Corridor.
In the early 1990s, Amtrak tested several different high-speed trains from Europe on the Northeast Corridor. An X 2000 train was leased from Sweden for test runs from October 1992 to January 1993, followed by revenue service between Washington, D.C., and New York City from February to May and August to September 1993. Siemens showed the ICE 1 train from Germany, organizing the ICE Train North America Tour which started to operate on the Northeast Corridor on July 3, 1993.
Building and development With the testing of the trains from Europe complete, Amtrak was able to define a set of specifications for high-speed equipment and in October 1994, Amtrak requested bids from train manufacturers for a trainset that could reach . A consortium of Bombardier (75%) and GEC Alsthom (now Alstom) (25%) was selected in March 1996.
In 1999, Amtrak unveiled its plan for the Acela Express, a high-speed train on the Northeast Corridor between Washington, D.C., and Boston. Several changes were made to the corridor to make it suitable for higher-speed electric trains. The Northend Electrification Project extended existing electrification from New Haven, Connecticut, to Boston to complete the overhead power supply along the route, and several grade crossings were improved or removed. Prior to 2000, all trains bound for Boston had to switch to diesel power at New Haven.
A pilot trainset was completed by early 2000 and sent to Transportation Technology Center (TTC) for testing in June 2000. An inaugural VIP run of the Acela occurred on November 16, 2000, followed by the first revenue run on December 11, 2000, a few months after the intended date.
Cost Amtrak's original contract with the Bombardier-Alstom consortium was for the delivery of 20 trainsets (six coaches each, with power cars at front and rear) for $800 million. By 2004, Amtrak had settled contract disputes with the consortium, paying a total of $1.2 billion for the 20 trainsets plus 15 extra high-speed locomotives and the construction of maintenance facilities in Boston, New York, and Washington.
Impact of the Acela
By 2005, Amtrak's share of the common-carrier market between New York and Boston had reached 40%, from 18% pre-Acela. With the increasing popularity of the faster, modern Acela Express, Metroliner service was phased out in late 2006. To meet the demand, more Acela services were added in September 2005. By August 2008 crowding had become noticeable.
By 2011, the Acela fleet had reached half of its designed service life. Amtrak proposed several replacement options, including one as part of its A Vision for High-Speed Rail in the Northeast Corridor. In 2011, Amtrak announced that forty new Acela coaches would be ordered in 2012 to increase capacity on existing trainsets. The existing trains would have received two more coaches, lengthening the trainsets from a 1-6-1 configuration to 1-8-1 (power car—passenger cars—power car). The longer trainsets would have required the modifications of the Acela maintenance facilities in Boston, New York and Washington. The first of the stretched trainsets was to have entered service in fiscal year 2014. This plan was cancelled in 2012 in favor of replacing, rather than refurbishing, the Acela fleet.
In January 2014, Amtrak issued a request for proposals on 28 or more new model Acela trainsets, in a combined order with the California High-Speed Rail Authority. After discussions with manufacturers, Amtrak and the California High Speed Rail Authority concluded their needs were too disparate for common rolling stock and decided not to pursue the joint option.
Fleet replacement After the joint high-speed trainset procurement with California collapsed in 2014, Amtrak proceeded on its own. On August 26, 2016, then–Vice President Joe Biden announced a $2.45 billion federal loan to finance new equipment and Northeast Corridor upgrades, and Amtrak selected Alstom's Avelia Liberty design, marketed as the NextGen Acela, ordering 28 trainsets to replace the 20 first-generation sets. The larger fleet was intended to allow hourly New York–Boston service all day and half-hourly New York–Washington service at peak hours, with assembly taking place at Alstom's plants in Hornell and Rochester, New York.
Body construction began at Hornell in October 2017, when Alstom also unveiled the trainset's livery, and a prototype subsequently entered testing at the Transportation Technology Center in Pueblo, Colorado, and on the Northeast Corridor. The trainsets were initially expected to begin revenue service in 2021, with the entire fleet delivered the following year.
The program ultimately ran more than three years behind schedule. Amtrak and Alstom attributed much of the slippage to unforeseen difficulty completing the computer-simulation modeling required by the Federal Railroad Administration (FRA) and to compatibility problems between the European-derived design and the corridor's curve-heavy, century-old infrastructure. An October 2023 audit by the Amtrak Office of Inspector General found the program over budget and reported that each of the 12 trainsets built so far had defects—among them hydraulic leaks in the tilt system, corrosion caused by water pooling between cars, and five windows that had shattered spontaneously—and that Alstom had begun building trains before validating the crash-simulation model needed for FRA certification. With the new fleet delayed, the first-generation sets were kept running well beyond their planned retirement, and Amtrak began removing several from service to harvest parts.
On January 13, 2024, after the simulation model finally passed, the FRA cleared the Avelia Liberty for on-track testing between Washington and Boston. Qualification testing was completed and a spring 2025 launch was targeted; after that date passed, Amtrak revised its estimate to "coming soon". On August 7, 2025, Amtrak announced that the trains would debut on August 28, and the first five trainsets entered revenue service that day.
Legacy and influence Since its introduction, the Acela has become a symbol of modern passenger rail in the United States and has influenced subsequent high-speed rail planning efforts across the country. The Train's operational success demonstrated consistent public demand for faster, business-oriented intercity travel, reinforcing federal and state interest in high-speed rail corridors such as California High-Speed Rail and Brightline West. Amtrak's experience with Acela's maintenance and ridership patterns has also informed the design of future services and infrastructure standards along the Northeast Corridor and beyond.
Branding Before the introduction of the Acela, several classes of trains operated on the Northeast Corridor: the express Metroliners, the Philadelphia-New York Clockers, Empire Service trains between New York City and Niagara Falls via the Empire Corridor, Keystone Service trains between New York City and to Harrisburg via the Keystone Corridor, and the umbrella term NortheastDirect, applied to other trains on the corridor (in addition to unique names assigned to many departures).
Amtrak announced the Acela name in March 1999 as a part of the original announcement of the service itself. The branding team based the name "Acela" on the concepts of "acceleration" and "excellence". At the same time, Amtrak launched what it called the Capstone Program, a short-lived plan to rebrand the NortheastDirect, Keystone Service and Empire Service trains as Acela Regional and the Clocker trains as Acela Commuter.
The Acela Regional name was first applied to NortheastDirect trains 130–133 in 2000. Those trains became the first electrified trains to run on the full Northeast Corridor between Washington, D.C. and Boston. As more trains were electrified, they too were rebranded.
Following widespread rider confusion in distinguishing the three services, Amtrak removed the branding from the lower-speed Acela Regional and Acela Commuter trains in 2003.
In 2019, Amtrak shortened the name of the service from Acela Express to simply Acela.Date and observation of train name change at Further examples of the dropping of "Express" on all press-releases since then at "Media Room", Amtrak
Rolling stock First-generation trainsets