98188 ZIP Code, Seattle, WA
98188 is a ZIP code in Seattle, Washington in King County. It covers 8.1 square miles of land. The closest ZIP codes are 98158, 98148 and 98057. 27,311 people live here in 11,430 households. At about 3,386 people per square mile it has suburban density, and owners and renters are mixed (42% own). Median household income is $76,438, below the Washington median of $98,141.
Quick facts
- Mailing city: Seattle, WA
- County: King County
- Land area: 8.1 sq mi
- Population: 27,311
- Median household income: $76,438
- Carrier routes: 17 (11,394 homes)
Key figures
| Measure | Value |
|---|---|
| Residents | 27,311 |
| Households | 11,430 |
| Median household income | $76,438 |
| Income per person | $41,508 |
| Median age | 37.5 |
| Homeowners | 41.5% |
| Median home value | $456,400 |
| Median rent | $1,678 |
| Bachelor's degree or higher | 28.1% |
| Average commute (minutes) | 24.2 |
| Households with kids under 18 | 25.5% |
| Moved in the past year | 15.3% |
| Below the poverty line | 8.5% |
| Broadband internet | 89.8% |
| Speak a non-English language at home | 47.3% |
Household income
| % of households | Value |
|---|---|
| <$10K | 3.4% |
| $10–15K | 3.3% |
| $15–25K | 3.5% |
| $25–35K | 4.2% |
| $35–50K | 13.7% |
| $50–75K | 21.0% |
| $75–100K | 15.6% |
| $100–150K | 19.8% |
| $150–200K | 7.7% |
| $200K+ | 7.9% |
Age
| % of all residents | Value |
|---|---|
| <10 | 11.8% |
| 10–19 | 9.6% |
| 20–24 | 5.8% |
| 25–34 | 18.0% |
| 35–44 | 18.1% |
| 45–54 | 11.3% |
| 55–64 | 11.2% |
| 65–74 | 8.3% |
| 75+ | 5.7% |
Tenure
| % of housing units | Value |
|---|---|
| Owned, with mortgage | 23.8% |
| Owned outright | 14.9% |
| Rented | 53.2% |
| Vacant | 8.2% |
Type of building
| % of housing units | Value |
|---|---|
| Detached house | 31.9% |
| Townhome | 3.2% |
| 2–4 units | 7.4% |
| 5–19 units | 21.1% |
| 20+ units | 32.3% |
| Mobile / other | 4.3% |
Businesses in 98188
1,496 business establishments with 43,850 employees (ZIP Codes Business Patterns 2023).
- Retail Trade: 274
- Accommodation and Food Services: 196
- Wholesale Trade: 132
- Health Care and Social Assistance: 130
- Professional, Scientific, and Technical Services: 110
- Other Services (except Public Administration): 104
- Transportation and Warehousing: 100
- Administrative and Support and Waste Management and Remediation Services: 96
EDDM carrier routes
98188 has 17 USPS carrier routes with 11,394 residential and 1,594 business mailboxes. Open the EDDM route map.
Carrier routes in 98188
98188 has 17 USPS carrier routes (17 city (C)) with 11,394 residential and 1,594 business mailboxes. Routes range from 1 homes (C047) to 1,257 homes (C034); the median route has 691 homes. The Census counted 11,430 households in 98188 (2020–2024 average); USPS counts current mailboxes, including new and vacant homes.
| Homes per route | Routes |
|---|---|
| 1–249 | 2 |
| 250–499 | 1 |
| 500–749 | 6 |
| 750–999 | 3 |
| 1,000–1,499 | 4 |
| 1,500+ | 0 |
Best routes in 98188 for…
Most businesses
For B2B offers: office supplies, cleaning, IT, catering and commercial services.
- Route C057 — USPS business mailboxes 344, 0 homes
- Route C017 — USPS business mailboxes 316, 790 homes
- Route C047 — USPS business mailboxes 279, 1 homes
- Route C007 — USPS business mailboxes 218, 358 homes
- Route C035 — USPS business mailboxes 160, 589 homes
Select these 5 routes on the route map
Every carrier route in 98188
| Route | Type | Homes | Businesses | Est. median income | Est. owners | Est. families with kids | Est. moved in past year |
|---|---|---|---|---|---|---|---|
| C006 | City | 551 | 73 | $54,831 | — | — | — |
| C007 | City | 358 | 218 | $75,811 | — | — | — |
| C017 | City | 790 | 316 | $75,811 | — | — | — |
| C019 | City | 1,207 | 44 | $93,491 | — | — | — |
| C025 | City | 125 | 6 | $92,048 | — | — | — |
| C034 | City | 1,257 | 8 | $55,605 | — | — | — |
| C035 | City | 589 | 160 | $104,946 | — | — | — |
| C036 | City | 701 | 4 | $92,048 | — | — | — |
| C037 | City | 662 | 38 | $122,392 | — | — | — |
| C046 | City | 1,055 | 19 | $47,325 | — | — | — |
| C047 | City | 1 | 279 | $114,931 | — | — | — |
| C056 | City | 681 | 15 | $79,136 | — | — | — |
| C057 | City | 0 | 344 | $75,811 | — | — | — |
| C066 | City | 884 | 12 | $79,136 | — | — | — |
| C067 | City | 664 | 1 | $104,786 | — | — | — |
| C077 | City | 1,086 | 48 | $78,490 | — | — | — |
| C088 | City | 783 | 9 | $47,325 | — | — | — |
Income, owners, families and movers are estimates for each route (how we estimate them); mailbox counts are current USPS figures. Open 98188 on the EDDM route map.
How route demographics are estimated
Mailbox counts come from USPS; demographics are estimates
The number of homes and businesses on each carrier route is the current USPS EDDM count. The Census Bureau does not publish figures for carrier routes, so income, homeownership, ages, families, movers and housing age on a route are EDDM2GO estimates built from Census block groups (neighborhood areas of roughly 600 to 3,000 people).
How a route gets its figures: the block-group length-share method
We trace each route's streets every 25 meters and record which block group each stretch falls in. The route's homes are spread along its streets in proportion to length, so a route with 60% of its street length in one block group is assumed to have 60% of its homes there. Each block group then contributes its Census counts in proportion to the share of its housing units that sit on the route (capped at the whole block group). Medians are recalculated from the combined income, home-value and age brackets, the way the Census Bureau computes them, not averaged.
Margins of error
Census survey figures carry a margin of error at 90% confidence; we carry it through the calculation and show it as ±. Our margins treat the route-to-block-group split as exact, so the real uncertainty is larger. Routes with fewer than 100 estimated households, large margins, or streets we could not place are flagged.
Different years
USPS mailbox counts are current. Census figures are 5-year averages for 2020–2024, so a new subdivision may have more homes on the route today than the Census counted. Use the route figures to compare routes with each other, not as an exact head count.
Why some routes show identical figures
Two routes that run through the same block group get the same percentages and medians, because the Census publishes one set of figures for the whole block group. Their mailbox counts still differ, and those are exact.
Route and mailbox counts: USPS EDDM route data. Route demographics: EDDM2GO estimates from U.S. Census Bureau American Community Survey 5-year block-group data (2020–2024) and 2024 cartographic block-group boundaries. This product uses the Census Bureau Data API but is not endorsed or certified by the Census Bureau.
Nearby ZIP codes
- 98158 — SeaTac city, WA (1.7 mi)
- 98148 — Burien city, WA (2.5 mi)
- 98057 — Renton city, WA (3 mi)
- 98168 — Tukwila city, WA (3.2 mi)
- 98055 — Renton city, WA (3.4 mi)
- 98032 — Kent city, WA (3.8 mi)
- 98166 — Burien city, WA (3.8 mi)
- 98178 — Bryn Mawr-Skyway CDP, WA (3.8 mi)
Areas that include 98188
- Seattle, WA ZIP codes — 38 ZIP codes
- SeaTac, WA ZIP codes — 5 ZIP codes
- Tukwila, WA ZIP codes — 4 ZIP codes
- King County ZIP codes — 88 ZIP codes
- Washington ZIP code data
Where it ranks
- No. 18 of 77: fastest population growth in King County
- No. 8 of 32: fastest population growth in Seattle, WA
Mail every home in 98188
Route counts on this page price as Full Service 6.5 × 9 postcards: we print, bundle by carrier route and hand the mailing to USPS. Prefer to take it to the Post Office yourself? Print only costs less and you pay postage at drop-off.
Seattle EDDM mailing
EDDM guides
ZIP code statistics describe the Census ZIP Code Tabulation Area (ZCTA) 98188, which approximates the USPS ZIP code area. Census figures: American Community Survey 5-year estimates, 2020–2024.
Frequently asked questions
- What city is 98188 in?
- 98188 is a Seattle, WA mailing address. By land area, 51% lies inside Tukwila and 49% lies inside SeaTac.
- What county is 98188 in?
- 98188 is in King County.
- What is the population of 98188?
- About 27,311 people (±1,472), according to the Census Bureau's American Community Survey 5-year estimates for 2020–2024. The 2020 Census counted 27,851.
- What is the median household income in 98188?
- $76,438 (±$7,723), compared with $98,141 for Washington as a whole. Half the households in the ZIP code earn more and half earn less.
- How many carrier routes and mailboxes are in 98188?
- 17 USPS carrier routes with 11,394 residential and 1,594 business mailboxes (12,988 in all), from the route data stored by EDDM2GO. An EDDM mailing can target any combination of these routes.
- What ZIP codes are near 98188?
- The closest, measured center to center: 98158 (1.7 mi, SeaTac), 98148 (2.5 mi, Burien), 98057 (3 mi, Renton), 98168 (3.2 mi, Tukwila), 98055 (3.4 mi, Renton) and 98032 (3.8 mi, Kent).
This product uses the Census Bureau Data API but is not endorsed or certified by the Census Bureau.