99115 ZIP Code — Coulee City, WA

Grant County, Washington

ZIP code 99115 is located in Coulee City, Washington, within Grant County. It covers approximately 420.01 square miles and serves a population of 1,224 residents. This is a standard ZIP code in the Pacific (PT) timezone, served by area code 509.

About ZIP code 99115

The housing stock consists of a higher-than-average concentration of mobile homes. Most homes were built in the pre-1940, giving the area an established character. Median home value is $146,800. Owner-occupancy sits near the national average at 73%.

Median household income is $46,343. 54% of households receive Social Security income, suggesting a notable retiree or disability population.

The dominant occupation class is natural resources, construction, and trades, with agriculture and mining as the leading industry. The average commute of 23 minutes is near the national average.

College attainment at 17% is below the national average, consistent with a trades and production-oriented local economy.

Overall, ZIP code 99115 reflects a community defined by a trades-oriented workforce and a significant Social Security-dependent population.

1,224

population

420.01

sq mi land

Standard

ZIP type

Pacific (PT)

timezone

99115 ZIP code map

Cities in ZIP code 99115

Below are the cities the US Postal Service accepts for ZIP code 99115. Using any city not on this list may result in mail delivery delays.

City	Status
Coulee City	Preferred

Nearby ZIP codes

98851 Soap Lake (10.1 mi) 99135 Hartline (12.6 mi) 98832 Marlin (16.2 mi) 98858 Waterville (19.7 mi)

Demographics updated 05/2026

Population
Total population	1,224
Population density	3 / sq mi
State FIPS	53
County FIPS	025

Geography
Land area	420.01 sq mi
Water area	28.77 sq mi
Latitude	47.5441
Longitude	-119.3202
Timezone	Pacific (PT)
Area code	509

Total population by age

Gender

Race & ethnicity

Economics updated 05/2026

Household income

Income range	This ZIP	County avg	State avg
Under $50k	45.3%	42.1%	31.7%
$50k – $100k	44.7%	34.5%	30.6%
$100k – $200k	7.9%	19.6%	27.1%
Over $200k	2.2%	3.7%	10.6%

Demographics & statistics

1,224

Population

People per sq mi

48.7

Median age

$46,343

Median household income

$23,710

Per capita income

$146,800

Median home value

$689

Median monthly rent

73.3%

Home ownership

11.6%

Poverty rate

7.4%

Unemployment

873

Housing units

17.1%

Bachelor's or higher

Age distribution

Male Female

Under 5

5–9

10–14

15–19

20–24

25–34

35–44

45–54

55–59

60–64

117

65–74

122

75–84

85+

← Male

Female →

Age summary

Group	Count	%
Under 18	250	20.4%
18 and over	974	79.6%
65 and over	377	30.8%
Median age	48.7 years

Race & ethnicity

White 78.8%

Two or more races 10.5%

Hispanic or Latino 5%

American Indian / Alaska Native 2.3%

Black or African American 2.1%

Asian 1.2%

Other race 0.2%

Group	Count	%
White	1,015	78.8%
Two or more races	135	10.5%
Hispanic or Latino	64	5%
American Indian / Alaska Native	29	2.3%
Black or African American	27	2.1%
Asian	15	1.2%
Other race	3	0.2%

Household income

Income range	This ZIP	County avg	State avg
Under $50k	45.3%	42.1%	31.7%
$50k – $100k	44.7%	34.5%	30.6%
$100k – $200k	7.9%	19.6%	27.1%
Over $200k	2.2%	3.7%	10.6%

Under $10k 1.0%

$10k–$15k 8.1%

$15k–$25k 16.6%

$25k–$35k 10.6%

$35k–$50k 17.0%

$50k–$75k 26.7%

$75k–$100k 8.1%

$100k–$150k 10.8%

$150k–$200k 0.6%

$200k+ 0.4%

Range	% of households
Under $10k	1.0%
$10k–$15k	8.1%
$15k–$25k	16.6%
$25k–$35k	10.6%
$35k–$50k	17.0%
$50k–$75k	26.7%
$75k–$100k	8.1%
$100k–$150k	10.8%
$150k–$200k	0.6%
$200k+	0.4%
Median income	$46,343

Housing

Home values

Under $50k 10.6%

$50k–$100k 19.5%

$100k–$150k 21.6%

$150k–$200k 14.2%

$200k–$300k 19.5%

$300k–$500k 10.3%

$500k–$1M 4.2%

Housing overview

Metric	Value
Median home value	$146,800
Median rent / month	$689
Owner occupied	73.3%
Renter occupied	26.7%
Vacant	48.9%
Single-family detached	54.2%
Large apartment buildings	0.0%
Mobile homes	42.8%
Median rooms	4.8
Avg household size (owned)	2.13

Year built

Era	%
2020 or later	1.0%
2010–2019	6.9%
2000–2009	15.0%
1990–1999	13.9%
1980–1989	6.7%
1970–1979	14.7%
1960–1969	9.0%
1950–1959	3.3%
1940–1949	5.9%
1939 or earlier	23.4%

Bedrooms

Size	% of units
No bedroom (studio)	0.0%
1 bedroom	32.6%
2 bedrooms	25.6%
3 bedrooms	28.9%
4 bedrooms	6.0%
5+ bedrooms	6.8%

Vehicles per household

Vehicles	% of households
No vehicle	7.0%
1 vehicle	23.0%
2 vehicles	43.5%
3 or more	26.5%

Heating fuel

Fuel type	%
Utility gas	4.3%
Electricity	90.9%
Propane / LP gas	3.7%
Fuel oil	1.2%

Households & families

Household type	Count	%
Married-couple family	294	56.9%
Cohabiting couple	16	3.1%
Male householder, no spouse	86	16.6%
Female householder, no spouse	121	23.4%
Households with children under 18	121	23.4%
Households with seniors (65+)	255	49.3%
Average household size	2.37

Marital status

Status	Male	Female
Never married	14.3%	9.4%
Married	66.1%	65.5%
Separated	3.0%	6.4%
Widowed	11.9%	12.4%
Divorced	4.8%	6.2%

Education

Less than 9th grade 2.8%

Some HS, no diploma 7.9%

HS graduate 30.6%

Some college, no degree 26.8%

Associate's degree 14.8%

Bachelor's degree 14.7%

Graduate / professional 2.4%

Metric	%
HS diploma or higher	89.4%
Bachelor's or higher	17.1%

School enrollment (ages 3–17)

Type	Count	%
Nursery / preschool	0	0.0%
Kindergarten	4	2.4%
Elementary school	106	63.9%
High school	20	12.0%
College / grad school	36	21.7%

Employment

Industry of employment

Agriculture & mining 31.9%

Education & healthcare 27.1%

Arts, food & hospitality 6.8%

Retail trade 6.5%

Other services 6.0%

Manufacturing 4.5%

Construction 4.3%

Professional & management 4.0%

Transportation & utilities 3.3%

Public administration 3.3%

Wholesale trade 2.3%

Occupation

Category	%
Management, business & arts	25.6%
Service	15.1%
Sales & office	23.1%
Natural resources & construction	30.2%
Production & transportation	6.0%

Employment type

Type	%
Private sector	77.1%
Government	17.3%
Self-employed	5.0%
Unpaid family workers	0.5%

Commute

Method	%
Drive alone	75.1%
Carpool	6.0%
Public transit	0.0%
Walk	1.5%
Work from home	15.3%
Other means	2.0%
Avg commute (minutes)	23.0

Poverty

All people 11.6%

Under 18 years 1.6%

18 and over 14.2%

Married-couple families 9.9%

Female-led households 53.6%

Income support

Source	% of households
Social Security	54.0%
Retirement income	29.0%
Supplemental Security	8.9%
Cash public assistance	0.0%
Food stamps / SNAP	11.8%

Health indicators

Condition	%
Obesity	32.2%
High blood pressure	41.0%
High cholesterol	40.2%
Diabetes	13.1%
Heart disease	9.1%
Stroke	4.4%
Asthma	11.2%
Arthritis	32.0%
Kidney disease	4.0%
Pulmonary disease	9.3%
Cancer	9.1%

Behavior / access	%
Smoking	17.3%
Binge drinking	14.1%
No physical activity	22.1%
Less than 7 hrs sleep	29.0%
Depression	24.1%
Fair or poor health	17.4%
Poor mental health	14.7%
Poor physical health	13.9%
No health insurance	10.5%
Visited doctor (checkup)	73.6%
Visited dentist	65.8%
Cholesterol screening	90.3%
Teeth loss	12.9%

Veterans & disability

Veterans	Count	%
Civilian veterans	69	7.1%

Disability	%
Any disability	21.2%
Under 18	10.4%
18–64 years	18.3%
65 and over	33.2%

Health insurance coverage

Type	%
Private insurance	55.4%
Public insurance	52.1%
No insurance	4.3%
Uninsured under 19	0.8%

Language & origin

Language spoken at home (age 5+)

Language	Count	%
English only	1,104	90.2%
Spanish	0	0.0%
Other Indo-European	0	0.0%
Asian & Pacific Islander	0	0.0%
Other languages	0	0.0%

Place of birth & citizenship

Origin	Count	%
Native born (US)	1,212	99.0%
Born in same state	1,197	97.8%
Born in different state	928	75.8%
Foreign born	15	1.2%
Naturalized citizen	12	1.0%
Not a US citizen	5	41.7%

Ancestry

Ancestry	Count	%
Polish	160	13.1%
Arab	116	9.5%
French	87	7.1%
Italian	86	7%

Ancestry	Count	%
Dutch	46	3.8%
English	41	3.3%
German	3	0.2%

Technology access

Metric	% of households
Computer access	42.2%
Internet access	89.7%

Source: U.S. Census Bureau, American Community Survey 2025 estimates.

Frequently asked questions about ZIP code 99115

What city is ZIP code 99115 in?

ZIP code 99115 is primarily assigned to Coulee City, Washington.

What county is ZIP code 99115 in?

ZIP code 99115 falls within Grant County, Washington.

Does ZIP code 99115 have an older population?

31% of residents in ZIP code 99115 are 65 or older, above the national average of ~17%.

Does ZIP code 99115 have a large retiree population?

54% of households in ZIP code 99115 receive Social Security income, suggesting a significant retiree or disability population.

What is the typical home value in ZIP code 99115?

The median home value in ZIP code 99115 is $146,800.

What is the median household income in ZIP code 99115?

The median household income in ZIP code 99115 is $46,343, below the national median of ~$75,000.

What timezone is ZIP code 99115 in?

ZIP code 99115 observes the PST timezone.