Mono County (/ˈmoʊnoʊ/ MOH-noh) is a county located in the east central portion of the U.S. state of California. As of the 2020 census, the population was 13,195, making it the fourth-least populous county in California. The county seat is Bridgeport. The county is located east of the Sierra Nevada between Yosemite National Park and Nevada. The only incorporated town in the county is Mammoth Lakes, which is located at the foot of Mammoth Mountain. Other locations, such as June Lake, are also famous as skiing and fishing resorts. Located in the middle of the county is Mono Lake, a vital habitat for millions of migratory and nesting birds. The lake is located in a wild natural setting, with pinnacles of tufa arising out of the salty and alkaline lake. Also located in Mono County is Bodie, the official state gold rush ghost town, which is now a California State Historic Park.

Mono County was formed in 1861 from parts of Calaveras, Fresno and Mariposa counties. A portion of northern Mono County contributed to the formation of Alpine County in 1864; parts of the county's territory were given to Inyo County in 1866.

The county is named after Mono Lake which, in 1852, was named for a Native American Paiute tribe, the Mono people, who historically inhabited the Sierra Nevada from north of Mono Lake to Owens Lake. The tribe's western neighbors, the Yokuts, called them monachie, meaning "fly people" because they used fly larvae as their chief food staple and trading article.

Archeologists know almost nothing about the first inhabitants of the county, as little material evidence has been found from them. The Kuzedika, a band of Paiute, had been there many generations by the time the first anglophones arrived. The Kuzedika were hunter-gatherers and their language is a part of the Shoshone language.

According to the U.S. Census Bureau, the county has a total area of 3,132 square miles (8,110 km), of which 3,049 square miles (7,900 km) is land and 83 square miles (210 km) (2.6%) is water. The highest point in Mono County is White Mountain Peak which, at 14,252 feet (4,344 m), is the third-highest peak in California.

• Inyo National Forest (part)
• Humboldt–Toiyabe National Forest (part)
• Granite Mountain Wilderness (California)

Historical population

Census	Pop.	Note	%±
1870	430		—
1880	7,499		1,644.0%
1890	2,002		−73.3%
1900	2,167		8.2%
1910	2,042		−5.8%
1920	960		−53.0%
1930	1,360		41.7%
1940	2,299		69.0%
1950	2,115		−8.0%
1960	2,213		4.6%
1970	4,016		81.5%
1980	8,577		113.6%
1990	9,956		16.1%
2000	12,853		29.1%
2010	14,202		10.5%
2020	13,195		−7.1%
2023 (est.)	13,066		−1.0%
U.S. Decennial Census 1790–1960 1900–1990 1990–2000 2010 2020

In June 2021, U.S. News & World Report ranked the county with the third best life expectancy in the United States at 96.5 years old.

Mono County, California – Racial and ethnic composition
Note: the US Census treats Hispanic/Latino as an ethnic category. This table excludes Latinos from the racial categories and assigns them to a separate category. Hispanics/Latinos may be of any race.

Race / Ethnicity (NH = Non-Hispanic)	Pop 2000	Pop 2010	Pop 2020	% 2000	% 2010	% 2020
White alone (NH)	9,837	9,687	8,679	76.53%	68.21%	65.77%
Black or African American alone (NH)	53	42	68	0.41%	0.30%	0.52%
Native American or Alaska Native alone (NH)	267	239	177	2.08%	1.68%	1.34%
Asian alone (NH)	140	191	159	1.09%	1.34%	1.21%
Pacific Islander alone (NH)	10	11	26	0.08%	0.08%	0.20%
Other Race alone (NH)	82	33	78	0.64%	0.23%	0.59%
Mixed Race or Multi-Racial (NH)	190	237	501	1.48%	1.67%	3.80%
Hispanic or Latino (any race)	2,274	3,762	3,507	17.69%	26.49%	26.58%
Total	12,853	14,202	13,195	100.00%	100.00%	100.00%

Population, race, and income
Total population	14,016
White	11,313	80.7%
Black or African American	180	1.3%
American Indian or Alaska Native	633	4.5%
Asian	78	0.6%
Native Hawaiian or other Pacific Islander	47	0.3%
Some other race	1,459	10.4%
Two or more races	306	2.2%
Hispanic or Latino (of any race)	3,613	25.8%
Per capita income	$28,789
Median household income	$60,469
Median family income	$78,079

Places by population and race

Place	Type	Population	White	Other	Asian	Black or African American	Native American	Hispanic or Latino (of any race)
Aspen Springs	CDP	0	0.0%	0.0%	0.0%	0.0%	0.0%	0.0%
Benton	CDP	76	67.1%	0.0%	0.0%	0.0%	32.9%	27.6%
Bridgeport	CDP	456	82.7%	1.8%	0.0%	2.6%	12.9%	5.3%
Chalfant	CDP	749	100.0%	0.0%	0.0%	0.0%	0.0%	1.3%
Coleville	CDP	652	89.0%	7.7%	0.0%	3.4%	0.0%	38.3%
Crowley Lake	CDP	496	100.0%	0.0%	0.0%	0.0%	0.0%	8.9%
June Lake	CDP	406	100.0%	0.0%	0.0%	0.0%	0.0%	0.0%
Lee Vining	CDP	406	32.8%	13.1%	0.0%	0.0%	54.2%	50.7%
McGee Creek	CDP	107	100.0%	0.0%	0.0%	0.0%	0.0%	0.0%
Mammoth Lakes	Town	8,081	75.4%	18.6%	0.8%	1.8%	3.3%	35.7%
Mono City	CDP	126	89.7%	10.3%	0.0%	0.0%	0.0%	0.0%
Paradise	CDP	383	94.5%	4.4%	1.0%	0.0%	0.0%	12.0%
Sunny Slopes	CDP	149	100.0%	0.0%	0.0%	0.0%	0.0%	0.0%
Swall Meadows	CDP	461	100.0%	0.0%	0.0%	0.0%	0.0%	0.0%
Topaz	CDP	75	100.0%	0.0%	0.0%	0.0%	0.0%	0.0%
Walker	CDP	750	79.6%	13.2%	0.0%	0.0%	7.2%	10.7%
‡ Data for Mono County area of this CDP

Places by population and income

Place	Type	Population	Per capita income	Median household income	Median family income
Aspen Springs	CDP	0
Benton	CDP	76	$12,570	$7,414
Bridgeport	CDP	456	$21,597	$68,750	$78,500
Chalfant	CDP	749	$36,325	$64,018	$108,219
Coleville	CDP	652	$17,365	$56,591	$43,250
Crowley Lake	CDP	496	$41,610	$85,299	$96,500
June Lake	CDP	406	$22,958	$25,570
Lee Vining	CDP	406	$18,698	$70,840	$71,152
McGee Creek	CDP	107	$34,573	$85,990	$85,990
Mammoth Lakes	Town	8,081	$27,832	$56,521	$72,469
Mono City	CDP	126	$26,037	$49,020	$49,020
Paradise	CDP	383	$33,544	$81,736	$105,227
Sunny Slopes	CDP	149	$61,994	$128,310	$128,310
Swall Meadows	CDP	461	$53,616	$93,983	$94,331
Topaz	CDP	75
Walker	CDP	750	$23,381	$49,097	$54,028

The 2010 United States census reported that Mono County had a population of 14,202. The racial makeup of Mono County was 11,697 (82.4%) White, 47 (0.3%) African American, 302 (2.1%) Native American, 192 (1.4%) Asian, 11 (0.1%) Pacific Islander, 1,539 (10.8%) from other races, and 414 (2.9%) from two or more races. Hispanic or Latino of any race were 3,762 persons (26.5%).

Population reported at 2010 United States census
The County	Total Population	White	African American	Native American	Asian	Pacific Islander	other races	two or more races	Hispanic or Latino (of any race)
Mono County	14,202	11,697	47	302	192	11	1,539	414	3,762
Incorporated town	Total Population	White	African American	Native American	Asian	Pacific Islander	other races	two or more races	Hispanic or Latino (of any race)
Mammoth Lakes	8,234	6,643	29	49	128	5	1,151	229	2,772
Census-designated place	Total Population	White	African American	Native American	Asian	Pacific Islander	other races	two or more races	Hispanic or Latino (of any race)
Aspen Springs	65	62	0	0	2	0	0	1	1
Benton	280	199	1	59	1	0	15	5	38
Bridgeport	575	484	1	43	1	0	25	21	148
Chalfant	651	594	0	13	5	0	16	23	67
Coleville	495	386	6	10	8	0	62	23	110
Crowley Lake	875	769	4	6	11	0	60	25	128
June Lake	629	534	0	7	2	0	78	8	137
Lee Vining	222	126	0	25	0	0	64	7	96
McGee Creek	41	39	0	0	0	0	0	2	2
Mono City	172	156	0	1	2	0	2	11	37
Paradise	153	130	0	2	6	0	5	10	14
Sunny Slopes	182	159	0	2	7	4	0	10	3
Swall Meadows	220	201	0	3	5	0	2	9	6
Topaz	50	44	0	1	0	0	5	0	24
Walker	721	629	3	57	3	1	13	15	70
Other unincorporated areas	Total Population	White	African American	Native American	Asian	Pacific Islander	other races	two or more races	Hispanic or Latino (of any race)
All others not CDPs (combined)	637	542	3	24	11	1	41	15	109

As of the census of 2000, there were 12,853 people, 5,137 households, and 3,143 families residing in the county. The population density was 4/sq mi (1.5/km). There were 11,757 housing units at an average density of 4/sq mi (1.5/km). The racial makeup of the county was 84.2% White, 0.5% Black or African American, 2.4% Native American, 1.1% Asian, 0.1% Pacific Islander, 9.5% from other races, and 2.3% from two or more races. 17.7% of the population were Hispanic or Latino of any race. 13.4% were of German, 12.6% Irish and 11.4% English ancestry according to Census 2000. 84.0% spoke English and 15.1% Spanish as their first language.

There were 5,137 households, out of which 28.7% had children under the age of 18 living with them, 50.6% were married couples living together, 6.5% had a female householder with no husband present, and 38.8% were non-families. 26.6% of all households were made up of individuals, and 4.3% had someone living alone who was 65 years of age or older. The average household size was 2.43 and the average family size was 2.98.

In the county, the population was spread out, with 23.0% under the age of 18, 10.3% from 18 to 24, 33.4% from 25 to 44, 25.6% from 45 to 64, and 7.6% who were 65 years of age or older. The median age was 36 years. For every 100 females there were 121.8 males. For every 100 females age 18 and over, there were 126.8 males.

The median income for a household in the county was $44,992, and the median income for a family was $50,487. Males had a median income of $32,600 versus $26,227 for females. The per capita income for the county was $23,422. About 6.3% of families and 11.5% of the population were below the poverty line, including 12.2% of those under age 18 and 1.9% of those age 65 or over.

Population and registered voters
Total population	14,016
Registered voters	6,000	42.8%
Democratic	1,970	32.8%
Republican	2,167	36.1%
Democratic–Republican spread	-197	-3.3%
Independent	248	4.1%
Green	62	1.0%
Libertarian	43	0.7%
Peace and Freedom	17	0.3%
Americans Elect	0	0.0%
Other	5	0.1%
No party preference	1,488	24.8%

Cities by population and voter registration

City	Population	Registered voters	Democratic	Republican	D–R spread	Other	No party preference
Mammoth Lakes	8,081	36.5%	35.0%	29.3%	+5.7%	10.3%	29.1%
North Mono County	2,803	46.7%	28.5%	45.7%	-17.2%	5.3%	20.3%
South Mono County excluding Mammoth Lakes	3,130	55.6%	32.3%	40.5%	-8.2%	5.7%	20.8%

In November 2008, Mono County was one of just three counties in California's interior in which voters rejected Proposition 8 which sought to ban gay marriage. The county's voters rejected Proposition 8 by 55.5 percent to 44.5 percent. The other interior counties in which Proposition 8 failed to receive a majority of votes were neighboring Alpine County and Yolo County.

Mono County is in California's 3rd congressional district, represented by Republican Kevin Kiley.

In the state legislature Mono is in the 5th Assembly district, which is held by Republican Joe Patterson, and the 4th Senate district, which is held by Republican Marie Alvarado-Gil.

United States presidential election results for Mono County, California

Year	Republican		Democratic		Third party(ies)
	No.	%	No.	%	No.	%
2024	2,294	37.83%	3,522	58.08%	248	4.09%
2020	2,513	37.30%	4,013	59.56%	212	3.15%
2016	2,111	39.97%	2,773	52.51%	397	7.52%
2012	2,285	44.10%	2,733	52.75%	163	3.15%
2008	2,354	42.25%	3,093	55.52%	124	2.23%
2004	2,621	49.10%	2,628	49.23%	89	1.67%
2000	2,296	52.53%	1,788	40.91%	287	6.57%
1996	1,882	46.00%	1,580	38.62%	629	15.38%
1992	1,570	36.05%	1,489	34.19%	1,296	29.76%
1988	2,177	61.38%	1,284	36.20%	86	2.42%
1984	2,659	72.31%	962	26.16%	56	1.52%
1980	2,132	62.32%	865	25.29%	424	12.39%
1976	1,600	58.80%	1,025	37.67%	96	3.53%
1972	1,872	66.88%	828	29.58%	99	3.54%
1968	1,130	64.28%	465	26.45%	163	9.27%
1964	850	56.07%	666	43.93%	0	0.00%
1960	912	66.33%	457	33.24%	6	0.44%
1956	673	73.79%	237	25.99%	2	0.22%
1952	891	76.61%	264	22.70%	8	0.69%
1948	541	64.79%	255	30.54%	39	4.67%
1944	378	60.87%	242	38.97%	1	0.16%
1940	459	46.13%	523	52.56%	13	1.31%
1936	241	34.09%	458	64.78%	8	1.13%
1932	199	34.25%	374	64.37%	8	1.38%
1928	220	61.80%	127	35.67%	9	2.53%
1924	166	53.55%	45	14.52%	99	31.94%
1920	170	67.73%	56	22.31%	25	9.96%
1916	137	42.02%	158	48.47%	31	9.51%
1912	3	0.81%	182	49.32%	184	49.86%
1908	224	59.89%	121	32.35%	29	7.75%
1904	245	64.64%	82	21.64%	52	13.72%
1900	284	52.11%	258	47.34%	3	0.55%
1896	259	44.27%	315	53.85%	11	1.88%
1892	286	53.36%	166	30.97%	84	15.67%

The following table includes the number of incidents reported and the rate per 1,000 persons for each type of offense.

Population and crime rates
Population	14,016
Violent crime	49	3.50
Homicide	0	0.00
Forcible rape	3	0.21
Robbery	2	0.14
Aggravated assault	44	3.14
Property crime	253	18.05
Burglary	120	8.56
Larceny-theft	275	19.62
Motor vehicle theft	13	0.93
Arson	1	0.07

Cities by population and crime rates

City	Population	Violent crimes	Violent crime rate per 1,000 persons	Property crimes	Property crime rate per 1,000 persons
Mammoth Lakes	8,373	38	4.54	196	23.41

• U.S. Route 6
• U.S. Route 395
• State Route 89
• State Route 108
• State Route 120
• State Route 158
• State Route 167
• State Route 168
• State Route 182
• State Route 203
• State Route 266
• State Route 270

Eastern Sierra Transit Authority operates intercity bus service along U.S. 395, as well as local services in Mammoth Lakes. Service extends south to Lancaster, California (Los Angeles County) and north to Reno, Nevada.

Yosemite Area Regional Transit System (YARTS) also runs along U.S. 395 from Mammoth Lakes to Lee Vining before entering Yosemite National Park.

General aviation airports in Mono County include Bryant Field near Bridgeport, Mammoth Yosemite Airport and Lee Vining Airport. In December 2021, seasonal commercial air service by United Airlines to San Francisco, Los Angeles, and Denver began at the Eastern Sierra Regional Airport in Bishop, providing local service to southern Mono County.

• Mammoth Lakes

The population ranking of the following table is based on the 2010 census of Mono County.

† county seat

Rank	City/Town/etc.	Municipal type	Population (2010 Census)
1	Mammoth Lakes	Town	8,234
2	Crowley Lake	CDP	875
3	Walker	CDP	721
4	Chalfant	CDP	651
5	June Lake	CDP	629
6	† Bridgeport	CDP	575
7	Coleville	CDP	495
8	Benton	CDP	280
9	Lee Vining	CDP	222
10	Swall Meadows	CDP	220
11	Sunny Slopes	CDP	182
12	Mono City	CDP	172
13	Paradise	CDP	153
14	Benton Reservation (Utu Utu Gwaitu Paiute Tribe)	AIAN	76
15	Aspen Springs	CDP	65
16	Topaz	CDP	50
17	McGee Creek	CDP	41
18	Bridgeport Reservation (Paiute Indians)	AIAN	35

• List of school districts in Mono County, California
• National Register of Historic Places listings in Mono County, California

• Rockwell, G. L.; Honeywell, P. D. (2004). Water-quality data for selected stream sites in Bridgeport Valley, Mono County, California, April 2000 to June 2003. U.S. Geological Survey Data Series. Vol. 89. Reston, VA: U.S. Department of the Interior, U.S. Geological Survey.

• Official website
• Mono County Film and Tourism Commission