What is the most common county name?

How the names were counted

Each state counts once per name, using the county name without its suffix, so Washington County and Washington Parish count the same. Independent cities, Connecticut planning regions and DC are left out because they are not named counties. Alaska boroughs and census areas are included under their base names. The data is the 2024 Census Gazetteer list of 3,144 county-equivalents.

The 25 most common names

Where the names come from

10 of the 25 most common names are also surnames of US presidents: Washington, Jefferson, Jackson, Lincoln, Madison, Monroe, Grant, Adams, Johnson, Polk. The others come from other people and places the states chose to honor.

Name counts tell you nothing about size. The Washington counties range from Washington County, OR with 611,272 residents down to Washington County, CO with 4,771.

Why repeated names break data joins

A spreadsheet that lists "Washington County" without a state matches 31 places. Even with a state, names are fragile: spelling varies (St. vs Saint, De Kalb vs DeKalb), suffixes differ, and independent cities share names with counties. Join on the 5 digit FIPS code instead.

The county FIPS code lookup turns a name and state into a code, and the FIPS codes guide explains how the codes are built.

Names used only once

1,373 names, 76% of the total, appear in only one state. Texas has the most names found nowhere else, 155. A unique name is safe to search without a state, but a code is still the better key, since the code is the field federal county files are joined on.

Largest and smallest of the top five names

For each of the five most common names, the table shows the most and least populous county that carries it.

Same name across a state line

Of the 109 pairs of bordering states, 94 share at least one county name. The pair with the most shared names is Illinois and Indiana, with 43. When a search for a county name returns the wrong state, a neighbor with the same name is a common cause, so check the state before using a result. The bordering state comparisons list each pair side by side.

Searching by county name

Type a name into the lookup below and it lists every match with its state and code. For the top names that means a long list: a search for Washington returns 31 states, and within one state a county and an independent city can share a name, as in Virginia. Pick the row by state and code, then open its county page for the full profile. Names with a Saint prefix are stored in the Census spelling, usually "St.", so search for both forms if the first finds nothing.

Why the counts differ from other lists

Other lists of county names give different totals because they count differently. Some count every county-level unit, so a name can count more than once in a state. Some include independent cities, which would add the Virginia city names that match counties. Some still use Connecticut's eight historical counties, which adds names like Fairfield and Hartford.

The rule here is simple and stated: one vote per state per base name, from the current Census list, with independent cities, Connecticut planning regions and DC left out.