The West Pier is a ruined pier in Brighton, England. Designed by Eugenius Birch and opening in 1866, it was the first pier to be Grade I listed in England but has become increasingly derelict since its closure to the public in 1975. As of 2025^[update] only a partial metal framework remained.

The pier was constructed during a boom in pleasure pier building in the 1860s, and was designed to attract tourists to Brighton. It was the town's second pier, joining the Royal Suspension Chain Pier that opened in 1823. The West Pier was extended in 1893, and a concert hall was added in 1916. The pier reached its peak attendance at this time, with 2 million visitors between 1918 and 1919. Its popularity began to decline after World War II, and concerts were replaced by a funfair and tearoom. A local company took over ownership of the pier in 1965, but could not meet the increasing costs of maintenance and filed for bankruptcy.

The pier closed to the public in 1975 and fell into disrepair and gradually collapsed. Major sections fell into the sea during storms in late 2002, and two separate fires, both thought to be arson, in March and May 2003 destroyed most of the remaining structure, leading to English Heritage declaring it beyond repair. Some structured demolition took place in 2010 to make way for the i360 observation tower; further structural damage from storms has occurred since.

The West Pier Trust owns the remains and has proposed various renovation plans. Some schemes have been opposed by local residents and the owners of the nearby Palace Pier, claiming unfair competition.

The West Pier was constructed during a boom in pleasure pier building in the 1860s, during which 22 new piers were erected across Britain. It was designed by architect Eugenius Birch as a place for seaside visitors to enjoy fresh sea air. Some wealthy residents in the nearby Regency Square objected to construction, complaining that the planned toll houses at the entrance would spoil the view of the sea from their homes. It was felt that the pier would have a positive effect on property values in the town, so the pier was approved. Construction began in 1863 and the pier opened to the public on 6 October 1866.

The pier's length was 1,115 feet (340 m) with a width of 310 feet (94 m) at the pierhead. It was built with cast iron threaded columns screwed into the seabed. The superstructure's ironwork was manufactured by Robert Laidlaw, featuring an "oriental" style. By the opening, the pier was fitted with gas lamps with ornamental serpent designs, which had been directly influenced by similar examples inside the nearby Royal Pavilion. The pier had ornamental houses, two toll houses and glass screens at the pierhead to protect visitors from the weather. A New Scientist report covering Britain's piers called the pier Birch's "masterpiece".

In 1893, the pierhead was extended under the supervision of Birch's nephew, Peregrine, who added a pavilion with a capacity for 1,400 people. After the Royal Suspension Chain Pier was demolished following a storm in 1896, the West Pier became the only one on Brighton's seafront until the construction of the Palace Pier in 1899.

In April 1900, seven sailors from HMS Desperate drowned in bad weather as they approached the pier.