Lake and Peninsula Borough (Russian: Лейк-энд-Пенинсула, Leyk-end-Peninsula) is a borough in the state of Alaska. As of the 2020 census, the population was 1,476, down from 1,631 in 2010. The borough seat of King Salmon is located in neighboring Bristol Bay Borough, although is not the seat of that borough. The most populous community in the borough is the census-designated place of Port Alsworth. With an average of 0.017 inhabitants per square kilometre (0.044 inhabitants/sq mi), the Lake and Peninsula Borough is the least densely populated organized county-equivalent in the United States; only the unorganized Yukon-Koyukuk Census Area has a lower density.

The borough has an area of 32,922 square miles (85,270 km), of which 23,652 square miles (61,260 km) is land and 9,270 square miles (24,000 km) (28.2%) is water. The borough contains Iliamna Lake, the largest lake in Alaska and third largest within United States borders, and occupies most of the Alaska Peninsula. Its land area is larger than that of San Bernardino County, California, the largest county in the contiguous Lower 48 states.

• Bethel Census Area, Alaska – north
• Kenai Peninsula Borough, Alaska – east
• Kodiak Island Borough, Alaska – southeast
• Aleutians East Borough, Alaska – west
• Bristol Bay Borough, Alaska – west
• Dillingham Census Area, Alaska – west

• Alagnak Wild River
• Alaska Maritime National Wildlife Refuge (part of the Alaska Peninsula unit)
  • Sutwik Island
• Alaska Peninsula National Wildlife Refuge (part)
• Aniakchak National Monument and Preserve
• Becharof National Wildlife Refuge (part)
  • Becharof Wilderness (part)
• Katmai National Park and Preserve (part)
  • Katmai Wilderness (part)
• Lake Clark National Park and Preserve (part)
  • Lake Clark Wilderness (part)

Historical population

Census	Pop.	Note	%±
1990	1,668		—
2000	1,823		9.3%
2010	1,631		−10.5%
2020	1,476		−9.5%
2023 (est.)	1,331		−9.8%
U.S. Decennial Census 1990–2000 2010–2020

As of the census of 2000, there were 1,823 people, 588 households, and 418 families residing in the borough. The population density was 0.059 people per square mile (0.023 people/km). There were 1,557 housing units at an average density of 0.05 per square mile (0.019/km). The racial makeup of the borough was 18.76% White, 0.05% Black or African American, 73.51% Native American, 0.22% Asian, 0.16% Pacific Islander, 0.33% from other races, and 6.97% from two or more races. 1.15% of the population were Hispanic or Latino of any race. About 5.41% reported speaking a Yupik language at home, while 3.87% speak Alutiiq and 1.23% an Athabaskan language.

Some 44.70% of households had children under the age of 18 living with them, 48.50% were married couples living together, 9.70% had a female householder with no husband present, and 28.90% were non-families. About 24.70% of all households were made up of individuals, and 3.90% consisted of a sole occupant 65 years of age or older. The average household size was 3.10 and the average family size was 3.74.

In the borough, the age of the population was spread out, with 37.80% under the age of 18, 8.50% from 18 to 24, 28.00% from 25 to 44, 20.20% from 45 to 64, and 5.40% who were 65 years of age or older. The median age was 29 years. For every 100 females, there were 113.50 males. For every 100 females age 18 and over, there were 124.10 males.

The dominant religion is Orthodox Christianity.

The Borough is governed by an elected assembly. The Borough's mayor is Glen R. Alsworth, Sr. The deputy mayor is Myra J. Olsen. The other members of the assembly are Randy Alvarez, Scott Anderson, Alvin Pedersen, Michelle Pope-Ravenmoon, and Christina Salmon-Bringhurst.

United States presidential election results for Lake and Peninsula Borough, Alaska

Year	Republican		Democratic		Third party(ies)
	No.	%	No.	%	No.	%
2020	234	36.34%	358	55.59%	52	8.07%
2016	174	43.28%	193	48.01%	35	8.71%
2012	143	39.29%	212	58.24%	9	2.47%
2008	299	59.56%	185	36.85%	18	3.59%
2004	224	65.88%	114	33.53%	2	0.59%
2000	297	57.34%	196	37.84%	25	4.83%
1996	235	44.76%	240	45.71%	50	9.52%
1992	291	48.26%	152	25.21%	160	26.53%
1988	342	67.06%	162	31.76%	6	1.18%
1984	446	78.94%	105	18.58%	14	2.48%
1980	225	54.09%	130	31.25%	61	14.66%
1976	212	58.08%	131	35.89%	22	6.03%
1972	180	48.91%	170	46.20%	18	4.89%
1968	195	44.72%	189	43.35%	52	11.93%
1964	82	18.72%	356	81.28%	0	0.00%
1960	121	36.45%	211	63.55%	0	0.00%

Despite King Salmon being the borough seat, it is not in Lake and Peninsula Borough and instead in Bristol Bay Borough, therefore it is not included in the list.

• Chignik
• Egegik
• Newhalen
• Nondalton
• Pilot Point
• Port Heiden

• Kijik

• List of airports in the Lake and Peninsula Borough

• Official website

Media related to Lake and Peninsula Borough, Alaska at Wikimedia Commons

• Borough map: Alaska Department of Labor

58°24′N 156°11′W / 58.40°N 156.18°W / 58.40; -156.18