ZIP code 45040 is in Mason (59% of residents) and Landen (1.5%), in Warren County, Ohio. 40% of its residents live outside city limits. It is in Ohio's 1st congressional district. Its state senate district is State Senate District 7; its state house district is State House District 56.
Elected in 2024 under OH's previous congressional map; this district's lines changed for the 120th Congress (seated January 3, 2027).
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).
45 voting precincts overlap ZIP 45040.
Map them, with each precinct's share of the ZIP's residents.
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ZIP 45040 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.