The Congress Street line was extended past Union Station to Stroudwater Village.

The Portland Railroad Company extended service through Westbrook (via Forest Avenue, Woodfords Corner and Evergreen Cemetery on Stevens Avenue, initially, then to Morrills Corner) to South Windham and Gorham by acquisition of the Westbrook, Windham & Naples Railway.

Another extension occurred to Bradley's Corner (between the Libbytown and Rosemont neighborhoods), bringing the mileage of the line to 15.7 miles (25.3 km).

Electrification through overhead wires began in the late 19th century, starting with the Deering line.

[5]In 1894, a short extension was made from Lunts Corner to East Deering post office via Washington Avenue, followed by an extension from Fort Allen Park through Morning Street to Congress Street, then along Congress to complete a loop to Atlantic Avenue.

On the Stroudwater line, rails were laid west from Railroad Square on St. John Street to today's Park Avenue, passing beneath Maine Central Railroad's trestle bridge, then along Park Avenue to connect to the existing line at Congress Street.

[5] The last horse-drawn car ran in December 1895,[6] by which point there was 21.67 miles (34.87 km) of single-track lines.

Increasing automobile ownership made electric railway travel less convenient through the 1920s.