2000
#12,955
National surname rank
Recorded bearers 2,171
First available Census row
Per 100,000 0.80
Rare Last name
Manahan
Derived from the Irish Ó Manacháin, meaning "descendant of Manachán," a personal name of uncertain origin.
According to the 2020 US Census Bureau surname tables, roughly 2,554 Americans carry the last name Manahan. That puts it at #13,160 in the national surname ranking, appearing at a frequency of 0.75 per 100,000 people (about 1 in 134,203 residents).
This page is the full Name Census profile for the Manahan 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
2.6K
1 in 134,203
Census rank
#13,160
2020 decennial data
Per 100,000
0.7
Frequency rate
Recorded bearers
2.2K
rare in the US
Popularity narrative
The Census Bureau recorded 2,227 bearers of the surname Manahan in its 2020 decennial surname file. At a rate of 0.75 per 100,000 residents, it holds the 13160th position in the national surname ranking.
Among Census respondents with the surname Manahan, the largest self-reported group is White at 66.9%. The next largest groups are Asian/Pacific Islander (20.5%) and Hispanic (4.5%).
Origin
Meaning and origin of Manahan
The surname Manahan has its origins in Ireland, tracing back to the 16th century. It is believed to have derived from the Irish Gaelic name "Ó Manacháin," which means "descendant of Manachán." Manachán itself is a diminutive form of the Irish name "Manach," meaning "monk."
One of the earliest recorded mentions of the Manahan name can be found in the Annals of the Four Masters, a chronicle of medieval Irish history. The name appears in an entry from the year 1587, referring to a figure named Muircheartach Ó Manacháin, who was described as a distinguished scholar and poet from County Roscommon.
The Manahan surname was particularly prominent in the counties of Roscommon and Sligo in the western province of Connacht. It is also closely associated with the placename "Manahan" or "Monahin," a townland in County Roscommon. This suggests that the surname may have originated from a specific location within that area.
In the 17th century, a notable figure bearing the Manahan name was Edmond Manahan, who lived from 1628 to 1698. He was a prominent Catholic priest and philosopher from County Sligo, known for his writings on metaphysics and natural philosophy.
Another historical figure with the Manahan surname was John Manahan, born in 1758 in County Roscommon. He was a prominent Irish rebel who participated in the Irish Rebellion of 1798 and was later exiled to Australia for his involvement.
In the 19th century, one of the most renowned individuals with the Manahan name was Ambrose Manahan, born in 1813 in County Sligo. He was a celebrated poet and writer who contributed significantly to the Irish literary tradition of his time.
Other notable figures with the Manahan surname include Patrick Manahan (1823-1892), a Catholic priest and educator from County Roscommon, and Michael Manahan (1844-1907), a successful businessman and politician who served as a member of the Irish House of Commons.
While the Manahan name has its roots in Ireland, it has since spread to various parts of the world due to Irish emigration over the centuries. However, its origins can be traced back to the western counties of Ireland, particularly Roscommon and Sligo, where it was most prevalent in historical records.
Demographics
Ancestry and ethnicity for Manahan
Among Census respondents with the surname Manahan, the largest self-reported group is White at 66.9%. The next largest groups are Asian/Pacific Islander (20.5%) and Hispanic (4.5%).
The bar chart below shows how Manahan 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 Manahan surname at the time of the 2020 Census, not any inherent property of the name itself.
- White66.9% · 1,490
- Asian and Pacific Islander20.5% · 457
- Hispanic or Latino4.5% · 100
- Black or African American4.0% · 90
- Two or more races4.0% · 88
- American Indian and Alaska Native0.1% · 2
Timeline
Historical Census data for Manahan
Manahan 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
#11,722
National surname rank
Recorded bearers 2,673
+502 bearers (+23.1%)
Per 100,000 0.91
Rank movement Up 1,233 places
2020
#13,160
National surname rank
Recorded bearers 2,227
-446 bearers (-16.7%)
Per 100,000 0.75
Rank movement Down 1,438 places
| Year | Rank | Count | Per 100K | Count change | Rank change |
|---|---|---|---|---|---|
| 2000 | #12,955 | 2,171 | 0.80 | First available Census row | First available Census row |
| 2010 | #11,722 | 2,673 | 0.91 | +502 bearers (+23.1%) | Up 1,233 places |
| 2020 | #13,160 | 2,227 | 0.75 | -446 bearers (-16.7%) | Down 1,438 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 Manahan 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 | #11,722 | #13,160 | -12.3% |
| Count | 2,673 | 2,227 | -16.7% |
| Per 100K | 0.91 | 0.75 | -18.1% |
Between the 2010 and 2020 Census, the number of Manahan bearers went from 2,673 to 2,227 (-16.7% change). The surname moved down 1,438 positions in the national ranking, going from #11,722 to #13,160.
FAQ
Manahan surname: questions and answers
How many people in the U.S. have the surname Manahan?
Name Census estimates that about 2,554 living Americans carry the surname Manahan. Using the current population baseline, that works out to roughly 1 in 134,203 residents.
How common is Manahan?
Manahan ranks #13,160 in the 2020 Census surname tables and is classified on this site as "Rare." The Census recorded the name at a frequency of 0.75 per 100,000 residents, which is about 1 people out of every 100,000.
How many people with this surname were counted in the Census?
The raw 2020 Census file counted 2,227 people with the surname Manahan. That is different from the site's living-bearer estimate (2,554), which projects the surname's present-day count by applying the Census frequency rate to the current U.S. population.
What does 0.75 per 100,000 actually mean?
It is the Census Bureau's normalized frequency measure. A rate of 0.75 per 100,000 means that if you picked a random group of 100,000 U.S. residents, you would expect about 1 of them to have the surname Manahan.
Has Manahan become more or less common over time?
Between 2010 and 2020, the surname Manahan went from 2,673 recorded bearers to 2,227. That is a decrease of 446 (-16.7%). In the national ranking it fell from #11,722 to #13,160.
What does the Census say about the background of Manahan?
Among Census respondents with the surname Manahan, the largest self-reported group is White at 66.9%. The next largest groups are Asian/Pacific Islander (20.5%) and Hispanic (4.5%). 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 Manahan in the 2020 Census, accounting for 66.9% (1,490 people in the source table).
What is the full ancestry breakdown?
Manahan appears across multiple self-reported groups in the Census data. The largest shares in the 2020 file are White (66.9%), Asian/Pacific Islander (20.5%), Hispanic (4.5%). 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 Manahan (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 Manahan mean?
Derived from the Irish Ó Manacháin, meaning "descendant of Manachán," a personal name of uncertain origin. 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 Manahan (0.75 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 Americans have the surname Manahan?
For a faster, more casual read, check HowManyOfMe.org — our sister site built around that single question.