Boundary Atlas

ZIP code 96789: Mililani Town, HI

ZIP code 96789 is in Mililani Town (51% of residents), Mililani Mauka (39%) and Waipio Acres (10%), in Honolulu County, Hawaii. It is in Hawaii's 1st congressional district. Its state senate districts are State Senate District 17 (65%), State Senate District 18 (31%) and State Senate District 23 (4.7%); its state house districts are State House District 38 (53%), State House District 37 (37%), State House District 46 (10%) and State House District 39 (<0.1%).

54,732residents (2020 Census)
26.4 sq miland area
3cities and towns
1congressional district
11voting precincts

See it on the mapAll of Hawaii

City and county

City or townShare of ZIP residents
Mililani Town51%
Mililani Mauka39%
Waipio Acres10%

CountyShare of ZIP residents
Honolulu County100%

Town or county subdivisionShare of ZIP residents
Ewa CCD100%
Wahiawa CCDland only

Congressional district

Congressional districtShare of ZIP residents
Hawaii's 1st congressional district (HI-01)100%
Hawaii's 2nd congressional district (HI-02)land only

Elected officials

OfficeMemberContactShare of residents
U.S. Representative (HI-01)Ed Case (D)202-225-2726100%
U.S. Representative (HI-02)Jill N. Tokuda (D)202-225-4906<0.1%
U.S. SenatorBrian Schatz (D)202-224-3934 · contact formstatewide
U.S. SenatorMazie K. Hirono (D)202-224-6361 · contact formstatewide
State Senator (State Senate District 17)Donovan Dela Cruz (Democratic)65%
State Senator (State Senate District 18)Danielle Bass (Democratic)31%
State Senator (State Senate District 23)Brenton Awa (R)4.7%
State Representative (State House District 38)Lauren Matsumoto (R)53%
State Representative (State House District 37)Trish La Chica (Democratic)37%
State Representative (State House District 46)Amy Perruso (Democratic)10%
State Representative (State House District 39)Elijah Pierick (R)<0.1%

Officials serving now (members of Congress until January 3, 2027). Sources: State legislators: Open States (public domain); Members of Congress: the @unitedstates project, congress-legislators (CC0).

Local government

State legislative districts

State senate districtShare of ZIP residents
State Senate District 1765%
State Senate District 1831%
State Senate District 234.7%

State house districtShare of ZIP residents
State House District 3853%
State House District 3737%
State House District 4610%
State House District 39<0.1%

Voting precincts

11 voting precincts overlap ZIP 96789. Map them, with each precinct's share of the ZIP's residents.

Get this in your AI agent

Your agent can get these cities, counties, districts and precincts with their shares, and their GeoJSON boundaries, from Boundary Atlas. Add https://atlas-production-d344.up.railway.app/mcp to Claude, ChatGPT, Cursor or Codex (free, no key; how), then:

related_geographies(id="us:zcta:96789")

ZIP 96789 here is the Census Bureau's ZIP Code Tabulation Area, which approximates the USPS ZIP Code; PO-box-only ZIPs have none. Districts are the maps in force for the November 3, 2026 election.