Both services used the Boston and Maine's Connecticut River Line south of Vernon, Vermont, rather than the route prior to 2014 over the New England Central.

This was made possible by the use of cab cars, or engineer positions on both ends, so that the train could travel east from Springfield to Palmer, Massachusetts, and reverse direction to continue north on the Central Vermont.

On October 30, 2006, the Vermonter began stopping at the towns of Wallingford and Windsor Locks (near Bradley International Airport) in Connecticut for the first time.

[8] In the late 2000s, Amtrak and the State of Vermont considered the purchase of diesel multiple unit (DMU) trainsets for use on the New Haven–St.

Albans stretch of the line,[9] with Amtrak offering a $2 million grant to help make the switch and market the new service.

[12] On October 5, 2012, the Federal Railroad Administration announced the completion of track work within the states of Vermont and New Hampshire for the above-mentioned stimulus plan.

[16][17] The move was forced after the pandemic prompted Vermont Governor Phil Scott to declare a state of emergency.

At Palmer, it made a backup move on to the New England Central Railroad (NECR), as no direct track connection existed.

The re-route and consequent elimination of the backup move saved about 25 minutes of travel time between Springfield and Brattleboro when the line rehabilitation was completed, in early 2015.

In 2012, the Federal Railroad Administration awarded $7.9 million to allow for the upgrade of the existing freight rail line between St. Albans and the Canada–US border.

The agreement would allow for the establishment of a preclearance customs and immigration facility within Central Station in Montreal that could be used by both an extended Vermonter and Amtrak's existing Adirondack train.

[33][34] Enabling legislation was enacted by the United States on December 16, 2016, as the Promoting Travel, Commerce, and National Security Act of 2016.

[36] As of late 2021, according to Vermont transportation officials, while the United States remains active on the project, interest and engagement from regional and federal authorities on the Canadian side has frozen.

Saving around 1 hour 30 minutes between New Haven and Montreal, this scenario is forecast to incentivize an additional 31,100 to 40,900 riders per year by 2040.

A key component to increasing the speed limit would be the installation of centralized traffic control from Greenfield to Brattleboro and from White River Junction to the border.

[42] The arrangement will offer a near seamless transition between power sources at New Haven, 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, fold-out tray tables.