Immediately north of Half Moon Bay is Pillar Point Harbor and the unincorporated community of Princeton-by-the-Sea.

The city's infrastructure is heavily integrated with the coast, including the Pillar Point Harbor, major roads, and the fire department.

[8] Because of this geography, a 2022 study[update] found that the city had over 123 buildings vulnerable to sea level rise.

[8] Half Moon Bay began as a rural agricultural area, primarily used by Mission San Francisco de Asís (established in 1776) for grazing cattle, horses, and oxen.

Originally, San Benito, the town was renamed Spanishtown and attracted a thriving fishing industry in addition to its continued importance to coastal agriculture.

Spanishtown became a racially diverse community, settled by Canadians, Chinese, English, Germans, Irish, Mexicans, Italians, Scots, Portuguese, and Pacific Islanders.

The construction of Pedro Mountain Road in 1914 provided better access to San Francisco and probably contributed to the railroad's demise by 1920.

During Prohibition "rum runners" took advantage of dense fog and hidden coves in the area to serve several roadhouses and inns, some of which operate today as restaurants (e.g., Moss Beach Distillery).

Real growth in the area came after World War II with the construction of numerous subdivisions, eventually leading to Half Moon Bay's incorporation in 1959.

The economic crisis severely affected tourism, which generates the most revenue, and just when the city had finalized an $18 million settlement over a property lawsuit.

Dozens of meetings were held to decide where to cut the budget and finally, 75 percent of municipal employees were laid off and replaced with contract workers.

The early retirement was expected to save the city over $426,000 in annual General Fund expenses starting in 2015–16.

A spree killer opened fire at two farms with a semi-automatic pistol, killing seven people and critically injuring an eighth person.

[11] In 2024, Half Moon Bay politicians were criticized by California Governor Gavin Newsom for repeatedly delaying approval of a 40-unit apartment building for senior farmworkers.

Neighboring towns include El Granada, Princeton-by-the-Sea, Moss Beach, and Montara to the north and Purissima, San Gregorio, and Pescadero to the south.

Major local industries include agriculture (houseplants, floriculture, Christmas trees, pumpkins, artichokes), fishing, and tourism.

[8] The study found at least 123 buildings, including the Ritz Carlton (a major employer for the town), Pigeon Point Lighthouse and the Pescadero Cal Fire Station would be seriously threatened by erosion if sea level were to rise by 5 feet (1.5 m).

This is a man-made break with unusual waves shaped by reflections from the breakwater at Pillar Point Harbor.

For the 37th parallel north, the mild summer temperatures of Half Moon Bay are unmatched across the board.

[27] The remnants of the village of Purissima, perhaps the only ghost town in San Mateo County, are four miles (6.4 km) south of the city, near the junction of State Route 1 and Verde Road.

[30] The Half Moon Bay Airport hosts an annual benefit event in April, Pacific Coast Dream Machines, which features aircraft and automobiles.

The region around Half Moon Bay contains several state parks and beaches, including: At the north edge of the bay is the big wave surf area, Mavericks, off Pillar Point, where surfers challenge waves over 50 feet (15 m) tall.

Montara Mountain, located North of Half Moon Bay, is a popular outdoor recreation spot and home to the old Highway 1.

[34] Law enforcement for the City of Half Moon Bay is provided under a contract with the San Mateo County Sheriff's Office.

SamTrans routes 294 and 117 provide service to Half Moon Bay from the Hillsdale Caltrain station in San Mateo and Linda Mar in Pacifica, respectively.

The 1992 movie Raising Cain, which takes place and was filmed on the San Francisco Peninsula mentions a fictitious Half Moon Marsh.

Belinda Carlisle shot her music video for Circle in the Sand at Half Moon Bay.

Half Moon Bay is the title of a psychological thriller written by Jonathan and Jesse Kellerman.