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Washington ZIP Codes
Whitman County
Rosalia, WA
99170
99170 ZIP Code — Rosalia, WA
Whitman County, Washington
ZIP code 99170 is located in
Rosalia ,
Washington ,
within Whitman County .
It covers approximately 173.10 square miles and serves a population of
955 residents.
This is a standard ZIP code in the Pacific (PT) timezone,
served by area code 509 .
About ZIP code 99170
The housing stock consists of predominantly single-family detached homes. Most homes were built in the pre-1940, giving the area an established character. Median home value is $179,300. Owner-occupancy is high at 81%, well above the national average.
Median household income is $61,250. 32% of households receive Social Security income, suggesting a notable retiree or disability population.
The dominant occupation class is management, business, and professional, with education and healthcare as the leading industry. The average commute of 34 minutes is near the national average.
Educational attainment is near the national average, with 23% of residents holding a bachelor's degree or higher.
Overall, ZIP code 99170 reflects a community defined by high homeownership and a significant Social Security-dependent population.
99170 ZIP code map
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Cities in ZIP code 99170
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Nearby ZIP codes
Demographics
updated 05/2026
Population
Total population
955
Population density
6 / sq mi
State FIPS
53
County FIPS
075
Geography
Land area
173.10 sq mi
Water area
0.32 sq mi
Latitude
47.2583
Longitude
-117.4013
Timezone
Pacific (PT)
Area code
509
Economics
updated 05/2026
Household income
Income range
This ZIP
County avg
State avg
Under $50k
45.3%
55.9%
31.7%
$50k – $100k
26.1%
24.5%
30.6%
$100k – $200k
27.9%
15.6%
27.1%
Over $200k
0.7%
4.0%
10.6%
Demographics & statistics
$61,250
Median household income
$179,300
Median home value
23.3%
Bachelor's or higher
Age distribution
Age summary
Group Count %
Under 18 242 25.3%
18 and over 713 74.7%
65 and over 199 20.8%
Median age 45.8 years
Race & ethnicity
American Indian / Alaska Native
0.3%
Native Hawaiian / Pacific Islander
0.3%
Group Count %
White 831 84.9%
Two or more races 98 10%
Hispanic or Latino 24 2.5%
Other race 14 1.4%
Asian 6 0.6%
American Indian / Alaska Native 3 0.3%
Native Hawaiian / Pacific Islander 3 0.3%
Household income
Income range
This ZIP
County avg
State avg
Under $50k
45.3%
55.9%
31.7%
$50k – $100k
26.1%
24.5%
30.6%
$100k – $200k
27.9%
15.6%
27.1%
Over $200k
0.7%
4.0%
10.6%
Range % of households
Under $10k 4.7%
$10k–$15k 3.2%
$15k–$25k 15.5%
$25k–$35k 7.6%
$35k–$50k 8.9%
$50k–$75k 16.1%
$75k–$100k 8.9%
$100k–$150k 21.1%
$150k–$200k 7.1%
$200k+ 6.8%
Median income $61,250
Housing
Housing overview
Metric Value
Median home value $179,300
Median rent / month $906
Owner occupied 80.8%
Renter occupied 19.2%
Vacant 18.3%
Single-family detached 87.1%
Large apartment buildings 0.0%
Mobile homes 8.6%
Median rooms 6.7
Avg household size (owned) 2.56
Year built
Era %
2020 or later 0.0%
2010–2019 0.4%
2000–2009 2.8%
1990–1999 5.2%
1980–1989 7.1%
1970–1979 9.5%
1960–1969 3.9%
1950–1959 12.0%
1940–1949 8.4%
1939 or earlier 50.8%
Bedrooms
Size % of units
No bedroom (studio) 0.0%
1 bedroom 3.0%
2 bedrooms 27.1%
3 bedrooms 43.9%
4 bedrooms 19.6%
5+ bedrooms 6.5%
Vehicles per household
Vehicles % of households
No vehicle 5.3%
1 vehicle 12.9%
2 vehicles 41.1%
3 or more 40.8%
Heating fuel
Fuel type %
Utility gas 38.9%
Electricity 38.2%
Propane / LP gas 3.9%
Fuel oil 6.6%
Wood 8.4%
Households & families
Household type Count %
Married-couple family 217 57.1%
Cohabiting couple 31 8.2%
Male householder, no spouse 62 16.3%
Female householder, no spouse 70 18.4%
Households with children under 18 92 24.2%
Households with seniors (65+) 127 33.4%
Average household size 2.51
Marital status
Status Male Female
Never married 26.2% 19.0%
Married 61.4% 60.3%
Separated 3.6% 0.5%
Widowed 0.8% 9.5%
Divorced 8.0% 10.6%
Education
Some college, no degree
23.9%
Graduate / professional
9.0%
Metric %
HS diploma or higher 96.3%
Bachelor's or higher 23.3%
School enrollment (ages 3–17)
Type Count %
Nursery / preschool 24 11.2%
Kindergarten 6 2.8%
Elementary school 95 44.2%
High school 57 26.5%
College / grad school 33 15.3%
Employment
Industry of employment
Education & healthcare
29.2%
Agriculture & mining
15.3%
Transportation & utilities
5.5%
Public administration
5.5%
Finance & real estate
3.4%
Professional & management
3.2%
Arts, food & hospitality
2.5%
Occupation
Category %
Management, business & arts 42.4%
Service 15.9%
Sales & office 20.3%
Natural resources & construction 10.3%
Production & transportation 11.2%
Employment type
Type %
Private sector 64.2%
Government 19.4%
Self-employed 16.4%
Unpaid family workers 0.0%
Commute
Method %
Drive alone 79.0%
Carpool 2.8%
Public transit 0.0%
Walk 6.8%
Work from home 10.0%
Other means 1.4%
Avg commute (minutes) 34.0
Poverty
Married-couple families
16.6%
Female-led households
37.5%
Income support
Source % of households
Social Security 31.8%
Retirement income 20.3%
Supplemental Security 2.9%
Cash public assistance 3.2%
Food stamps / SNAP 12.6%
Health indicators
Condition %
Obesity 34.1%
High blood pressure 34.8%
High cholesterol 35.3%
Diabetes 10.4%
Heart disease 7.7%
Stroke 3.6%
Asthma 11.2%
Arthritis 29.3%
Kidney disease 3.4%
Pulmonary disease 8.1%
Cancer 7.9%
Behavior / access %
Smoking 16.9%
Binge drinking 16.1%
No physical activity 20.5%
Less than 7 hrs sleep 29.2%
Depression 26.9%
Fair or poor health 15.6%
Poor mental health 15.2%
Poor physical health 12.3%
No health insurance 9.9%
Visited doctor (checkup) 71.5%
Visited dentist 67.4%
Cholesterol screening 89.4%
Teeth loss 12.3%
Veterans & disability
Veterans Count %
Civilian veterans 61 8.6%
Disability %
Any disability 14.3%
Under 18 5.4%
18–64 years 12.8%
65 and over 29.1%
Health insurance coverage
Type %
Private insurance 57.7%
Public insurance 44.4%
No insurance 7.3%
Uninsured under 19 5.2%
Language & origin
Language spoken at home (age 5+)
Language Count %
English only 874 91.5%
Spanish 1 0.1%
Other Indo-European 1 0.1%
Asian & Pacific Islander 0 0.0%
Other languages 0 0.0%
Place of birth & citizenship
Origin Count %
Native born (US) 938 98.2%
Born in same state 933 97.7%
Born in different state 641 67.1%
Foreign born 5 0.5%
Naturalized citizen 17 1.8%
Not a US citizen 17 100.0%
Ancestry
Ancestry Count %
Italian 236 24.7%
French 146 15.3%
Polish 40 4.2%
Ancestry Count %
Arab 21 2.2%
English 1 0.1%
Technology access
Metric % of households
Computer access 39.8%
Internet access 93.4%
Source: U.S. Census Bureau, American Community Survey 2025 estimates.
Frequently asked questions about ZIP code 99170
What city is ZIP code 99170 in?
ZIP code 99170 is primarily assigned to Rosalia, Washington.
What county is ZIP code 99170 in?
ZIP code 99170 falls within Whitman County, Washington.
Is ZIP code 99170 mostly owner-occupied?
81% of occupied units in ZIP code 99170 are owner-occupied, well above the national average.
What is the typical home value in ZIP code 99170?
The median home value in ZIP code 99170 is $179,300.
What is the population of ZIP code 99170?
ZIP code 99170 has an estimated population of 955 residents, with a density of 6 people per square mile.
What is the median household income in ZIP code 99170?
The median household income in ZIP code 99170 is $61,250, below the national median of ~$75,000.
What timezone is ZIP code 99170 in?
ZIP code 99170 observes the PST timezone.
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