[2] In early 2023, it was announced that southern Maine would receive $8 million in American Rescue Plan funds to increase bus-service frequency and improve accessibility at bus stops.

[5] In late 2023, it was reported that Maine could receive, over five years, around $250 million under the federal Bipartisan Infrastructure Law to improve public transportation.

[6] As of 2023, twelve operators provide bus and coach services in Maine, the largest being Greater Portland Metro.

The Maine State Ferry Service serves (from Rockland) Vinalhaven, North Haven and Matinicus Isle; (from Lincolnville) Isleboro; and (from Bass Harbor) Swan's Island and Frenchboro.

According to U.S. News & World Report, Maine is ranked 19th in public transit usage and 43rd in transportation infrastructure.

[18] Owls Head's Knox County Regional Airport (KRKD) was built during World War II.

[2] Local bus services include Biddeford Saco Old Orchard Beach Transit, Brunswick Link, Community Connector, Cooperative Alliance for Seacoast Transportation, Greater Portland Metro, Island Explorer, Lewiston-Auburn CityLink, Sanford Transit and South Portland Bus Service.

The terminal for each route, except the number 70 Zoom Turnpike Express,[20] is the Saco Transportation Center, from which connections to Amtrak's Downeaster can be made.

The route begins hourly from Brunswick's Amtrak station and connects to the BlueLine Commuter service and the Metro BREEZ express bus to and from Portland.

[22] WMTS operates several small commuter buses which serve Androscoggin, Franklin and Oxford counties:[9] the Lewiston-Auburn Citylink, the GreenLine Commuter (Farmington to Lewiston-Auburn), Lisbon Connection (Lisbon Falls to Lewiston), BlueLine Express (for employees of Bath Iron Works traveling from Lewiston), BlueLine Commuter (Lewiston-Auburn to Bath), a Farmington-Rangeley route (once per month), GreenLine Connection (Canton, Peru, Mexico and Rumford) and Bath CityBus (see below).

[23] In September 2023, a contribution of $17,500 from the Immigrant Resource Center of Maine allowed the service to waive fares for six months.

The Portland Transportation Center, at Thompson's Point, is a major transfer point (and the origin of route number 1 and the Metro BREEZ express service), where connections can be made to the Downeaster train, to Concord Coach Lines buses and to other local bus routes.

[32] Route 8 is known as the Peninsula Loop (running between Hannaford on Preble Street and Whole Foods Market via downtown Portland).

They used the money for bus stop improvements, transit signal priority and a reduced-fare promotion, as well as a pilot “Microtransit” program.

[33] The Island Explorer, operated by Ellsworth-based Downeast Transportation,[2] is a seasonal (June to October) service in Down East Maine.

[36] Downeast Transportation was awarded a $23 million grant in 2024 to replace its propane-running fleet with electric versions.

[35] The same year, construction began in Trenton on the Acadia Gateway Center, a hub for bus transportation to and from Mount Desert Island.

[23] MidCoast Public Transportation's Rockland Downtown Area Shuttle (DASH) runs eight times each weekday between Rockland's Rankin Center and Hannaford, while its Belfast DASH runs seven times each weekday between Belfast's Volunteers of America and Wight Street.

[53] There are three main inter-city bus services: Concord Coach Lines, Greyhound and Metro BREEZ.

Some of its destinations include Lexington, Kentucky; Myrtle Beach, South Carolina; Niagara Falls and Lancaster County, Pennsylvania.

[73] Amtrak's Downeaster serves Boston's North Station from Brunswick, with its Maine stops being in Freeport, Portland, Old Orchard Beach, Saco and Wells.

In 2024, discussions began once more to bring passenger rail service to central Maine, with Lewiston, Waterville and Bangor potentially being served.

A joint proposal was filed with the Maine Legislature's Transportation Committee which would result in a $500,000 federal grant to study the pros and cons of the plan.

In December 2023, the grant was given to the Northern New England Passenger Rail Authority, operators of the Downeaster, to study whether an extension of the service from Brunswick to Rockland was feasible.