The Framingham and Lowell Railroad opened between its namesake cities on October 1, 1871. Its South Sudbury station and freight house were located on the east side of the tracks, on the north side of Boston Pond Road. The Central Massachusetts Railroad opened from Boston to Hudson, Massachusetts in October 1881. After going out of business in 1883, it was reopened by the Boston and Lowell Railroad in 1885, which was, in turn, acquired by the Boston and Maine Railroad in 1887. The Old Colony Railroad, which had acquired the F&L in 1879, constructed a union station at the southeast corner of the junction of the two lines around 1887-91. This Victorian-style station included a three-story tower. The Old Colony Railroad was leased by the New York, New Haven and Hartford Railroad in 1893, making South Sudbury one of a small number of stations which served both of New England's two largest railroads. Passenger service ended on the F&L in 1933. Service on the CM past Clinton Junction ended in 1932 and on the branch to Marlborough in 1939; by 1950, there were just four daily round trips. With such drastically-reduced traffic levels, it was no longer economical for the B&M to maintain the large Union Station. A small wooden station was built around 1952; after failed attempts to move and preserve it, Union Station was demolished. The Massachusetts Bay Transportation Authority was formed in August 1964 to subsidize suburban commuter rail service. On January 18, 1965, northside services were cut back to the boundaries of the MBTA funding district. Although the MBTA initially intended to discontinue the single remaining trips on the Central Massachusetts Branch and the Lexington Branch, they were kept at the last minute. However, the remaining CM trip was cut from Hudson to South Sudbury. On November 26, 1971, the remaining South Sudbury round trip was discontinued due to poor track conditions and dwindling ridership. The circa-1952 station building is still extant, and is in use as a private business. Part of the platform, a station sign reading "Sudbury", and a Railway Express Agency cart remain at the building.
