Green Cove Springs is a city in and the county seat of Clay County, Florida, United States. Green Cove Springs is a part of the Jacksonville, Florida Metropolitan Statistical Area. The population was 9,786 at the 2020 census, up from 6,908 at the 2010 census.

The city is named after the portion of the St. Johns River upon which it is built. The river bends here, and the area is sheltered by trees that are perennially green.

The area was first inhabited over 7,000 years ago by Native Americans attracted to a warm mineral spring. The hydrological spring, locally known as the "Original Fountain of Youth", attracted patrons in the 19th century to the spa town, where more than a dozen hotels were built near the spring to accommodate them. Today, the sulfur-scented spring water feeds an adjacent public swimming pool before flowing the short distance to the St. Johns River. The Green Cove Springs area was first developed by George J. F. Clarke in 1816 when he was provided land, under a Spanish land grant, to build a sawmill. Green Cove Springs was established in 1854 as White Sulfur Springs. Renamed in 1866, it became the Clay County seat in 1871.

Agriculture and tourism were the two primary economic activities in the area until the end of the 19th century, when Henry Flagler's railroad began taking tourists further south in Florida. In 1895, the Great Freeze destroyed the area's citrus crops, and tourism all but ended. The 1920s had renewed development, with automobile traffic once again bringing in tourists. The Great Depression of the 1930s marked the end of this period of growth for the city.

The first women's club in the state of Florida was established in Green Cove Springs in 1883. The Village Improvement Association led local efforts to beautify the town, and established its first public library.

The period immediately before and during World War II again brought new growth to Green Cove Springs. On September 11, 1940, the U.S. Navy opened Naval Air Station Lee Field in honor of Ensign Bejamin Lee, who had lost his life in a crash at Killinghome, England, during World War I. In August 1943, the facility was renamed Naval Air Station Green Cove Springs and consisted of four 5,000-foot (1,500 m) asphalt runways. One of the Marine Corps aviators training in the F4U Corsair Operational Training Unit at Lee Field in early 1945 was eventual television personality Ed McMahon. After the war, NAS Green Cove Springs was downgraded in status to a Naval Auxiliary Air Station (NAAS) as part of the greater NAS Jacksonville complex. Thirteen piers were constructed along the west bank of the St. Johns River adjacent to NAAS Green Cove Springs to house a U.S. Navy Atlantic Reserve Fleet, Florida "mothball fleet" of some 500 vessels, primarily destroyers, destroyer escorts, and fleet auxiliaries. In 1960, the Navy decommissioned NAAS Green Cove Springs and the pier facility. Some of the mothballed vessels were transferred to foreign navies, while others were relocated to other Reserve Fleet locations.

In 1984, the city annexed the former naval base into the city to use it for further growth and development as the Clay County Port and Reynolds Industrial Park. The air station is now a private airfield known as Reynolds Airpark (FAA airfield identifier FL60) with a single 5,000-foot (1,500 m) asphalt runway currently operational, although reportedly in poor condition. Though the original air traffic control tower is still standing, attached to one of the former Navy aircraft hangars, the airfield remains an uncontrolled facility.

Green Cove Springs is the birthplace of Charles E. Merrill (1885–1956), one of the founders of Merrill Lynch. The town's spring is described by his son James Merrill in the poem "Two From Florida", published in The Inner Room (1988).

Green Cove Springs is also the birthplace of Augusta Savage (née Augusta Christine Fells, February 29, 1892 – March 26, 1962). Savage was an African-American sculptor associated with the Harlem Renaissance.

Locally, the community is known as the home of Gustafson's Farm, a brand name of milk and dairy products sold throughout Florida. The main Gustafson Dairy Farm is located in Green Cove Springs and is one of the largest privately owned dairy farms in the Southeastern United States. Started in 1908, the main farm occupies nearly 10,000 acres (40 km) adjacent to the city limits. Gustafson's has many bottling plants across the state, stretching from Tallahassee in the west to Tampa and Cocoa in the south. All Gustafson products have the picture of the husband-and-wife founders, Frank and Agnes Gustafson (also known as Mama and Papa Gus), who along with their first cow on their farm (named "Buttercup") are prominently featured on the packaging of the dairy's products.

Scenes for the 1971 "B" monster movie Blood Waters of Dr. Z (or Zaat) were filmed here. The movie was satirized on the television program Mystery Science Theater 3000.

These sites are listed on the National Register of Historic Places:

• Clay County Courthouse
• Green Cove Springs Historic District
• St. Mary's Church
• “The Hellhouse” original rehearsal studio to Lynyrd Skynyrd

The city of Green Cove Springs is structured in a city council/city manager form of government, with the council functioning as the governing body. The city has had this form of government since the 1980 charter revision. The city council is composed of five members who are elected at large to three-year terms. The five-member council consists of the mayor, the vice mayor, and three council members. The mayor and vice mayor are elected by the council and serve in these positions for one year. As the official representative of the city, the mayor is responsible for all intergovernmental relations and for presiding over all meetings of the council. The vice mayor serves as the presiding officer for all council meetings in the mayor's absence. The current city manager is Steve Kennedy.

The current office holders are:

• Mayor Seat 3 - Connie Butler
• Vice Mayor Seat 5 - Steven Kelley
• City Council Seat 1 - Edward Gaw
• City Council Seat 2 - Matt Johnson
• City Council Seat 4 - Thomas Smith

The Green Cove Springs Police Department provides full law enforcement services within the incorporated city limits of Green Cove Springs. The agency is headed by a chief of police with two lieutenants acting as division commanders. The department currently consists of 29 sworn officers, part-time and full-time dispatchers, an evidence custodian, an administrative secretary, and two crossing guards. The agency has full-time officers assigned to the countywide Drug Task Force and Jacksonville Metro DEA Task Force, and also participates in the Clay County SWAT team. In addition to these specialized assignments, the police department is active in the North East Florida Intelligence Unit, North East Florida Burglary Detectives Unit, Northeast Florida Investigative Support Center, the Violent Crime Regional Coordinating Team, Sex Assault Task Force, and Domestic Violence Task Force.

The department serves a diverse community and handled approximately 32,974 calls for service in 2011, with an average response time of two minutes for calls of an emergency nature. The department makes use of mobile data terminals in all of their patrol vehicles for reporting and obtaining information on the streets. All officers receive advanced training in law enforcement, as well as career development.

In 2011, the police department became the first law enforcement agency in northeast Florida to use red-light cameras. The agency is also known for programs such as North East Florida Camp Cadet and the Teen Summit.

In April 2014, the agency moved into a newly built police station and emergency operations center at 1001 Idlewild Avenue.

The city of Green Cove Springs contracts with the Clay County Fire-Rescue Department for fire and medical services.

A U.S. post office was established at Hibernia on June 19, 1849, but its name was changed on October 17, 1853, to Magnolia Mills, and on July 30, 1866, it was changed to Green Cove Springs. The Hibernia post office was reestablished on February 16, 1855, and remained open until May 15, 1931, when it was closed and the area assigned to Green Cove Springs.

Green Cove Springs is located on the eastern border of Clay County at 29°59′34″N 81°41′2″W / 29.99278°N 81.68389°W / 29.99278; -81.68389 (29.992716, –81.683786), along the St. Johns River.

U.S. Route 17 passes through the center of town as Orange Avenue and leads north 28 miles (45 km) to downtown Jacksonville and south 26 miles (42 km) to Palatka. State Road 16 departs west from the center of the city and leads 27 miles (43 km) to Starke. SR 16 leaves eastbound from US 17 south of the city center and crosses the St. Johns River by the Shands Bridge, leading to St. Augustine 25 miles (40 km) to the east. By the late 2020s, the First Coast Expressway, a major toll bypass road connecting I-10 and I-95, is expected to pass to the west and south of Green Cove Springs.

According to the United States Census Bureau, the city has a total area of 9.9 square miles (25.6 km), of which 7.4 square miles (19.1 km) are land and 2.5 square miles (6.5 km), or 25.35%, are covered by water.

Historical population

Census	Pop.	Note	%±
1880	320		—
1890	1,106		245.6%
1900	929		−16.0%
1910	1,319		42.0%
1920	2,093		58.7%
1930	1,719		−17.9%
1940	1,752		1.9%
1950	3,291		87.8%
1960	4,233		28.6%
1970	3,857		−8.9%
1980	4,154		7.7%
1990	4,497		8.3%
2000	5,378		19.6%
2010	6,908		28.4%
2020	9,786		41.7%
2023 (est.)	10,130		3.5%
U.S. Decennial Census

Green Cove Springs racial composition
(Hispanics excluded from racial categories)
(NH = Non-Hispanic)

Race	Pop 2010	Pop 2020	% 2010	% 2020
White (NH)	4,920	6,862	71.22%	70.12%
Black or African American (NH)	1,291	1,275	18.69%	13.03%
Native American or Alaska Native (NH)	19	26	0.28%	0.27%
Asian (NH)	66	153	0.96%	1.56%
Pacific Islander or Native Hawaiian (NH)	12	25	0.17%	0.26%
Some other race (NH)	4	42	0.06%	0.43%
Two or more races/Multiracial (NH)	113	427	1.64%	4.36%
Hispanic or Latino (any race)	483	976	6.99%	9.97%
Total	6,908	9,786

As of the 2020 United States census, there were 9,786 people, 2,997 households, and 2,046 families residing in the city.

As of the 2010 United States census, there were 6,908 people, 2,379 households, and 1,737 families residing in the city.

As of the census of 2000, there are 5,378 people, 1,987 households, and 1,402 families residing in the city. The population density was 789.0 inhabitants per square mile (304.6/km). The 2,199 housing units averaged 322.6 units per square mile (124.6 units/km). The racial makeup of the city is 71.55% White, 24.40% African American, 0.41% Native American, 0.54% Asian, 0.04% Pacific Islander, 1.34% from other races, and 1.73% from two or more races. 5.08% of the population are Hispanic or Latino of any race.

Of the 1,987 households in 2000, 28.9% had children under the age of 18 living with them, 50.2% were married couples living together, 16.2% had a female householder with no husband present, and 29.4% were not families. About 24.8% of all households were made up of individuals, and 12.3% had someone living alone who was 65 years of age or older. The average household size was 2.51, and the average family size was 2.96.

In 2000, in the city, the population distribution was 23.7% under the age of 18, 8.1% from 18 to 24, 26.0% from 25 to 44, 25.0% from 45 to 64, and 17.2% who were 65 years of age or older. The median age was 40 years. For every 100 females, there were 98.8 males. For every 100 females age 18 and over, there were 98.3 males.

In 2000, the median income for a household in the city was $33,487, and for a family was $40,443. Males had a median income of $28,097 versus $22,040 for females. The per capita income for the city was $17,673. About 14.6% of families and 19.1% of the population were below the poverty line, including 30.2% of those under age 18 and 13.7% of those age 65 or over.

Green Cove Springs is part of the Clay County School District. The city is home to Charles E. Bennett Elementary School, Green Cove Springs Jr. High School, and the Bannerman Learning Center. Clay High School lies just feet outside of the western city limits.

• Kevin Allen (born 1965), racing driver
• Cliff Avril (born 1986), player in the National Football League
• Charles Thomas Butler (1906–1964), Major League Baseball pitcher
• Frank J. Canova Jr. (born 1956), electronics engineer, known for inventing the smartphone
• Caeleb Dressel (born 1996), swimmer and seven-time Olympic gold medalist
• Will Holden (born 1993), player in the National Football League
• Charles E. Merrill (1885–1956), American businessman and philanthropist
• Maxey Dell Moody Jr. (1913–1987), founder of MOBRO Marine, Inc.
• Augusta Fells Savage (1892–1962), sculptor and art educator, leader during the Harlem Renaissance of the 1920s

• Clay County Historical Society Museum
• Military Museum of North Florida

• Official website