First three digits · Washington
ZIP Codes Starting with
36 ZIP codes start with 993, sorted at the Spokane, WA (SCF 990) sectional center (USPS labeling list L005, effective October 1, 2026) in Washington: 35 residential ZIP codes across 9 counties and 1 PO Box or single-organization code (Census 2020 ZCTAs and GeoNames postal codes, October 2026).
What do the digits 993 mean?
The first digit, 9, is one of ten national areas (Alaska, California, Hawaii, Oregon, Washington, American Samoa, Guam, Northern Mariana Islands, Marshall Islands, Micronesia, Palau and Armed Forces Pacific). The first three, 993, route mail to a sectional center: USPS labeling list L005 (effective October 1, 2026) sends letters for 993 to the Spokane, WA (SCF 990) facility. The last two digits pick the delivery area. By residents, the largest town names among the 993 ZIP codes are Kennewick, Pasco, Richland, Walla Walla, Othello and West Richland.
The same facility sorts 7 prefixes, 258 ZIP codes in all: 835, 838, 990, 991, 992, 993, 994.
Where are the 993 ZIP codes?
Source: U.S. Census Bureau, 2020 ZCTA cartographic boundaries; ACS 2020-2024 5-year estimates (B19013).
All ZIP codes starting with 993
| County | ||||||
|---|---|---|---|---|---|---|
| 99301 | Pasco | Franklin County | 87,044 | 179 | $88k | $386k |
| 99302 | Pasco | Franklin County | PO Box or unique | – | – | – |
| 99320 | Benton City | Benton County | 9,879 | 47 | $90k | $374k |
| 99321 | Beverly | Grant County | 1,047 | 30 | $76k | – |
| 99322 | Bickleton | Klickitat County | 412 | 2 | – | – |
| 99323 | Burbank | Walla Walla County | 4,082 | 31 | $93k | $413k |
| 99324 | College Place | Walla Walla County | 10,137 | 3,658 | $63k | $369k |
| 99326 | Connell | Franklin County | 6,336 | 26 | $83k | $321k |
| 99328 | Dayton | Columbia County | 3,646 | 6 | $73k | $272k |
| 99329 | Dixie | Walla Walla County | 127 | 279 | – | $311k |
| 99330 | Eltopia | Franklin County | 1,210 | 14 | $140k | $554k |
| 99333 | Hooper | Whitman County | 151 | 2 | $98k | $450k |
| 99335 | Kahlotus | Franklin County | 229 | 2 | $92k | $250k |
| 99336 | Kennewick | Benton County | 50,735 | 3,787 | $63k | $324k |
| 99337 | Kennewick | Benton County | 33,287 | 201 | $99k | $396k |
| 99338 | Kennewick | Benton County | 20,633 | 582 | $111k | $552k |
| 99341 | Lind | Adams County | 765 | 2 | $69k | $238k |
| 99343 | Mesa | Franklin County | 3,215 | 18 | $60k | $253k |
| 99344 | Othello | Adams County | 19,534 | 40 | $65k | $282k |
| 99345 | Paterson | Benton County | 162 | 1 | $103k | $416k |
| 99346 | Plymouth | Benton County | 198 | 1 | $51k | $209k |
| 99347 | Pomeroy | Garfield County | 2,512 | 3 | $65k | $243k |
| 99348 | Prescott | Walla Walla County | 1,633 | 3 | $79k | $237k |
| 99349 | Mattawa | Grant County | 8,143 | 30 | $61k | $428k |
| 99350 | Prosser | Benton County | 14,837 | 25 | $81k | $339k |
| 99352 | Richland | Benton County | 37,430 | 1,560 | $100k | $474k |
| 99353 | West Richland | Benton County | 19,251 | 746 | $122k | $451k |
| 99354 | Richland | Benton County | 25,559 | 1,068 | $92k | $393k |
| 99356 | Roosevelt | Klickitat County | 378 | 1 | $56k | – |
| 99357 | Royal City | Grant County | 3,843 | 18 | $57k | $327k |
| 99359 | Starbuck | Columbia County | 94 | 2 | $61k | $135k |
| 99360 | Touchet | Walla Walla County | 1,350 | 8 | $93k | $455k |
| 99361 | Waitsburg | Walla Walla County | 1,992 | 9 | $91k | $296k |
| 99362 | Walla Walla | Walla Walla County | 42,853 | 141 | $73k | $430k |
| 99363 | Wallula | Walla Walla County | 145 | 5 | – | $253k |
| 99371 | Washtucna | Adams County | 394 | 2 | $78k | $218k |
Source: U.S. Census Bureau, ACS 2020-2024 5-year estimates; GeoNames postal codes (CC BY 4.0) for codes without a residential area.