2000
#141,788
National surname rank
Recorded bearers 108
First available Census row
Per 100,000 0.04
Very Rare Last name
Kelahan
Of Irish origin, a surname derived from the personal name Ceallachán meaning "bright-headed".
According to the 2020 US Census Bureau surname tables, roughly 122 Americans carry the last name Kelahan. That puts it at #152,339 in the national surname ranking, appearing at a frequency of 0.04 per 100,000 people (about 1 in 2,809,462 residents).
This page is the full Name Census profile for the Kelahan surname. You will find the Census Bureau frequency data, a multi-census history view, an ancestry and ethnicity breakdown based on self-reported demographics, the name's meaning and origin where available, and answers to the most common questions people ask about this surname.
Bearers in the US
122
1 in 2,809,462
Census rank
#152,339
2020 decennial data
Per 100,000
0.0
Frequency rate
Recorded bearers
106
very rare in the US
Popularity narrative
The Census Bureau recorded 106 bearers of the surname Kelahan in its 2020 decennial surname file. At a rate of 0.04 per 100,000 residents, it holds the 152339th position in the national surname ranking.
Among Census respondents with the surname Kelahan, the largest self-reported group is White at 96.2%. The next largest groups are Hispanic (3.8%).
Origin
Meaning and origin of Kelahan
The surname Kelahan is believed to have originated in Ireland, with roots tracing back to the medieval period. It is thought to be an Anglicized form of the Irish Gaelic name Ó Ceallaighán, which means "descendant of Ceallaighán." The name Ceallaighán is derived from the Irish word "ceallach," meaning "strife" or "contention."
The earliest known record of the name Kelahan appears in the Annals of the Four Masters, a chronicle of medieval Irish history, which mentions a Ceallachan mac Buadhachain who lived in the 9th century. This suggests that the name has a long history in Ireland, particularly in the province of Munster.
In the 16th and 17th centuries, the name Kelahan began to appear in various historical records and documents, such as the Fiants of the Tudor Sovereigns and the Petty's Census of Ireland in 1659. These records often show variations in spelling, including Calahan, Kellahan, and Kellehan.
One notable figure bearing the surname Kelahan was John Kelahan (1768-1854), an Irish-born American soldier who served in the War of 1812. Another was Patrick Kelahan (1809-1877), an Irish-born Catholic priest who ministered in Cincinnati, Ohio, and was renowned for his work with the city's poor and immigrant communities.
In later centuries, the Kelahan surname spread to other parts of the world, including Australia and New Zealand. One prominent individual was James Kelahan (1869-1949), a New Zealand politician who served as a member of parliament for the Labour Party in the early 20th century.
Another notable bearer of the name was John Kelahan (1907-1988), an Irish-born American actor who appeared in numerous films and television shows throughout his career, including roles in "The Untouchables" and "The Fugitive."
While the Kelahan surname has roots in Ireland, it is now found in various parts of the world, reflecting the global diaspora of Irish immigrants over the centuries. Despite its relatively small numbers, the name has left its mark on history through the achievements of individuals from diverse backgrounds.
Demographics
Ancestry and ethnicity for Kelahan
Among Census respondents with the surname Kelahan, the largest self-reported group is White at 96.2%. The next largest groups are Hispanic (3.8%).
The bar chart below shows how Kelahan bearers described their own race and ethnicity on the 2020 Census form. The Census Bureau groups responses into six broad categories: White, Black or African American, Hispanic or Latino, Asian and Pacific Islander, American Indian and Alaska Native, and Two or More Races. When a category has too few respondents for a given surname, the Bureau suppresses the figure to protect individual privacy, which is why some names show fewer than six slices.
Percentages are shown for every Census year so the breakdown stays comparable over time. When the source file also includes raw headcounts, Name Census shows those alongside the percentages in the legend.
Keep in mind that these are self-reported numbers. A person's surname does not determine their race or ethnicity, and the distribution you see here reflects the specific population who happened to carry the Kelahan surname at the time of the 2020 Census, not any inherent property of the name itself.
- White96.2% · 102
- Hispanic or Latino3.8% · 4
Timeline
Historical Census data for Kelahan
Kelahan appears in 3 published Census surname files: 2000, 2010, 2020. The cards below show how the name's rank and bearer count changed across each release.
2010
#148,347
National surname rank
Recorded bearers 111
+3 bearers (+2.8%)
Per 100,000 0.04
Rank movement Down 6,559 places
2020
#152,339
National surname rank
Recorded bearers 106
-5 bearers (-4.5%)
Per 100,000 0.04
Rank movement Down 3,992 places
| Year | Rank | Count | Per 100K | Count change | Rank change |
|---|---|---|---|---|---|
| 2000 | #141,788 | 108 | 0.04 | First available Census row | First available Census row |
| 2010 | #148,347 | 111 | 0.04 | +3 bearers (+2.8%) | Down 6,559 places |
| 2020 | #152,339 | 106 | 0.04 | -5 bearers (-4.5%) | Down 3,992 places |
For 2020, the Census Bureau published race and Hispanic-origin columns as counts rather than percentages. Name Census converts those counts back into shares so the ancestry section stays comparable with the older surname files.
Year on year
2010 vs 2020 Census
How has the Kelahan surname changed between Census years? The chart shows bearer count side by side, and the table compares rank, count, and frequency.
Census year comparison
20102020
| Metric | 2010 | 2020 | Change |
|---|---|---|---|
| Rank | #148,347 | #152,339 | -2.7% |
| Count | 111 | 106 | -4.5% |
| Per 100K | 0.04 | 0.04 | -11.3% |
Between the 2010 and 2020 Census, the number of Kelahan bearers went from 111 to 106 (-4.5% change). The surname moved down 3,992 positions in the national ranking, going from #148,347 to #152,339.
FAQ
Kelahan surname: questions and answers
How many people in the U.S. have the surname Kelahan?
Name Census estimates that about 122 living Americans carry the surname Kelahan. Using the current population baseline, that works out to roughly 1 in 2,809,462 residents.
How common is Kelahan?
Kelahan ranks #152,339 in the 2020 Census surname tables and is classified on this site as "Very Rare." The Census recorded the name at a frequency of 0.04 per 100,000 residents, which is about 0 people out of every 100,000.
How many people with this surname were counted in the Census?
The raw 2020 Census file counted 106 people with the surname Kelahan. That is different from the site's living-bearer estimate (122), which projects the surname's present-day count by applying the Census frequency rate to the current U.S. population.
What does 0.04 per 100,000 actually mean?
It is the Census Bureau's normalized frequency measure. A rate of 0.04 per 100,000 means that if you picked a random group of 100,000 U.S. residents, you would expect about 0 of them to have the surname Kelahan.
Has Kelahan become more or less common over time?
Between 2010 and 2020, the surname Kelahan went from 111 recorded bearers to 106. That is a decrease of 5 (-4.5%). In the national ranking it fell from #148,347 to #152,339.
What does the Census say about the background of Kelahan?
Among Census respondents with the surname Kelahan, the largest self-reported group is White at 96.2%. The next largest groups are Hispanic (3.8%). These figures come from the 2020 Census Bureau surname tables, based on how respondents described their own race and ethnicity.
Which group reports this surname most often?
White is the largest self-reported group for the surname Kelahan in the 2020 Census, accounting for 96.2% (102 people in the source table).
What is the full ancestry breakdown?
Kelahan appears across multiple self-reported groups in the Census data. The largest shares in the 2020 file are White (96.2%), Hispanic (3.8%). For 2020, the source file also published raw headcounts for each group, which is why this page can show both percentages and counts in the ancestry section.
Is this page using the latest Census data?
Yes. This page is using the latest surname file currently loaded on Name Census, which is 2020. The historical section above also keeps any older Census surname entries we have for Kelahan (2000, 2010, 2020).
Does the Census include every surname?
No. The Census Bureau only publishes surnames that appeared at least 100 times in a given decennial Census. That means very rare surnames are excluded entirely, and a surname can appear in one Census release but disappear from a later one if it falls below the reporting threshold.
Why don't the ancestry percentages always add up to exactly 100%?
There are two main reasons: rounding and suppression. The Census Bureau rounds published values, and it may suppress very small cells to protect privacy. For 2020, the Bureau also published raw group counts rather than direct percentages, so Name Census converts those counts back into shares for comparability across census years.
What does Kelahan mean?
Of Irish origin, a surname derived from the personal name Ceallachán meaning "bright-headed". The fuller origin note on this page goes into more detail.
Where does the surname data come from?
All surname statistics on Name Census are drawn from the US Census Bureau's decennial surname frequency tables. These files list every surname that appeared 100 or more times in the 2020 Census, along with a count, a per-100,000 rate, and a self-reported demographic breakdown. You can read the full explanation on our methodology page.
How does Name Census estimate living bearers?
For surnames, Name Census does not age cohorts the way it does for first names. Instead, it takes the Census Bureau's published frequency for Kelahan (0.04 per 100,000) and applies that rate to the current U.S. resident population to estimate how many living Americans have the surname today.
How many people have the surname Kelahan?
HowManyOfMe.org, our sister site, answers that with the living-bearer count in one glance.