Fourth Avenue never had a streetcar line or elevated railway due to the provisions of the assessment charged to neighboring property owners when the street was widened.

[8] In 1902, a committee of the West End Board of Trade announced their support for a subway line from the Battery to Coney Island via Atlantic or Hamilton Avenues in front of the Rapid Transit Commission.

[15] The first definite plans for a subway under Fourth Avenue were proposed by Rapid Transit Commission engineer William Barclay Parsons in 1903.

[15] In 1906, the plan for the Fourth Avenue subway included a spur via 86th Street running through Dyker Heights and Bensonhurst.

On May 31, 1907, the Rapid Transit Commission requested that the Board of Estimate rescind the above resolution so that bids of construction alone might be asked for, and it authorized the preparation of the plans and contracts.

In October and November 1907, the PSC approved the plans and contracts with modifications concerning grades and an increase in the height of the subway to fifteen feet.

Coler, the Brooklyn Borough President, objected to the committee, citing that Mr. Lewis, the Chief Engineer, was against the construction of the project.

Afterwards, Metz procured an injunction that restrained the Board from acting until the debt limit was established: this blocked any immediate action.

After hearings, General Tracy announced that the project was $150,000,000 within the debt limit, and Mayor George McClellan and Controller Metz joined with their colleagues to vote unanimously in favor of the Fourth Avenue subway line on March 27, 1908.

[18] Contracts were awarded on May 22, 1908, for the section between 43rd Street and the Manhattan Bridge, but the Board of Estimate did not approve them until a taxpayer's lawsuit regarding the city's debt was settled.

The construction of the line was expected to transform communities in South Brooklyn, such as Bay Ridge, Dyker Heights, Fort Hamilton, Bath Beach, and Coney Island.

A lease to the Fourth Avenue subway was given to the New York Municipal Railway Corporation, a subsidiary of the BRT, for forty-nine years as part of Contract 4.

The PSC directed its Chief Engineer to create plans on June 14, 1912, and the contracts for the extension, Route 11B, was awarded on September 16, 1912.

[8] In anticipation of the opening of the subway, several housing and development booms occurred along Fourth Avenue, particularly in Bay Ridge.

[25] A trial trip that ran earlier in the day ripped a piece off of the platform at DeKalb Avenue as it was too broad.

[27] Initially, service only ran via the Nassau Loop tracks to Chambers Street as the new subway under Broadway was not yet open.

[39] Work started in October 1917, but construction halted on May 18, 1918, because of a wartime shortage of materials and men due to World War I, and about half the station was completed.

[40]: 51 On August 25, 1922, the Transit Commission directed its chief engineer, Robert Ridgeway, to plan an extension of the Fourth Avenue Line from 87th Street to Fort Hamilton.

[43] On September 12, 1922, a meeting was held by the Transit Commission to determine whether a stop at 91st Street should be included as part of the planned extension.

"[50] As part of Contract 11B, the extension was built with two tracks, with the exception of a short three-track stretch just north of the terminal at 95th Street.

[52] As a result of a motion made by Commissioner LeRoy Harkness in front of the Transit Commission, the contract was set to be put back up for bid.

[53] On November 2, 1923, the Board of Estimate approved the contract for the line with T. A. Gillespie Company, the same contractor that had bid on the project earlier, but withdrew.

[56] Later that month, on February 28, the Board made public the bids for the contract to complete the 95th Street terminal station.

[60] In February 1928, bids were received by the BOT on a project to remove kiosk subway entrances from the median of Fourth Avenue and to relocate them to the sidewalk to improve safety for transit riders.

A group of level crossovers at the northern end of the station allowed all tracks access to both sides of the Manhattan Bridge and to the Montague Street Tunnel.

The Fourth Avenue local tracks led straight onto the Manhattan Bridge west of the station, while the Brighton line tracks led straight to the Montague Street Tunnel, so the crossovers allowed trains from both lines to switch between the bridge and the tunnel.

[73] This led to so many train delays on the Fourth Avenue and Brighton Lines that, in 1952, the junction was earmarked for "top priority" reconstruction.

A diamond crossover north of the station had caused frequent bottlenecks, but was removed during the realignment and replaced with two flying junctions.

[89][90] From January to May 2016, Grimshaw Architects worked on a design for the stations' renovation, with Arup Group acting as a consultant.

[94] The 2015–2019 Capital Program also called for several stations to be renovated with elevators to bring them into compliance with the Americans with Disabilities Act of 1990.