2000
#10,200
National surname rank
Recorded bearers 2,901
First available Census row
Per 100,000 1.08
Rare Last name
Hennigan
Anglicized form of Irish Ó hÉanacháin, meaning "descendant of Éanachán," a personal name derived from a diminutive of éan, meaning "bird."
According to the 2020 US Census Bureau surname tables, roughly 3,024 Americans carry the last name Hennigan. That puts it at #11,426 in the national surname ranking, appearing at a frequency of 0.88 per 100,000 people (about 1 in 113,345 residents).
This page is the full Name Census profile for the Hennigan 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.
For British records, Name Census UK has a British surname profile for Hennigan with 1881 census detail, origin facts and modern UK distribution where available.
Bearers in the US
3.0K
1 in 113,345
Census rank
#11,426
2020 decennial data
Per 100,000
0.9
Frequency rate
Recorded bearers
2.6K
rare in the US
Popularity narrative
The Census Bureau recorded 2,637 bearers of the surname Hennigan in its 2020 decennial surname file. At a rate of 0.88 per 100,000 residents, it holds the 11426th position in the national surname ranking.
Among Census respondents with the surname Hennigan, the largest self-reported group is White at 85.3%. The next largest groups are Black (8.2%) and Two or More Races (2.8%).
Origin
Meaning and origin of Hennigan
The surname Hennigan is of Irish origin and dates back to the medieval period. It is derived from the Gaelic personal name Ó hEanacháin, which means "descendant of Eanachán." The name Eanachán is a diminutive form of the name Eanach, meaning "bird-like" or "birdlike."
The Hennigan surname is believed to have originated in County Sligo, Ireland, where the family was initially based. Some of the earliest recorded instances of the name can be found in the Annals of the Four Masters, a chronicle of medieval Irish history written in the 17th century.
One of the earliest known bearers of the Hennigan surname was Tomaltach Ó hEanacháin, who was mentioned in the Annals of the Four Masters under the year 1328. He was described as the chief poet of the Ó Ruairc family, who were lords of West Breifne (modern-day County Leitrim and parts of County Cavan).
Another notable figure from medieval times was Giolla na Naomh Ó hEanacháin, who lived in the 15th century and was a renowned poet and scholar. His works are preserved in the Book of Ballymote, a valuable manuscript compiled in the late 14th century.
During the 16th and 17th centuries, the Hennigan surname was particularly prominent in County Sligo, where they held lands around the baronies of Carbury and Leyny. One notable member of the family was Donnchadh Ó hEanacháin, who was a prominent landowner and chieftain in the area during the early 17th century.
In the 18th century, the name Hennigan began to spread beyond County Sligo, with members of the family settling in other parts of Ireland, as well as in England and North America. One famous bearer of the name was Michael Hennigan (1776-1841), an Irish-born soldier who fought in the Napoleonic Wars and later settled in Canada.
Other notable individuals with the Hennigan surname include Bridget Hennigan (1832-1899), an Irish-American philanthropist and founder of the Hennigan School in Boston, and John Hennigan (1861-1917), an Irish-American labor leader and politician who served as the 14th Lieutenant Governor of Massachusetts.
Demographics
Ancestry and ethnicity for Hennigan
Among Census respondents with the surname Hennigan, the largest self-reported group is White at 85.3%. The next largest groups are Black (8.2%) and Two or More Races (2.8%).
The bar chart below shows how Hennigan 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 Hennigan surname at the time of the 2020 Census, not any inherent property of the name itself.
- White85.3% · 2,249
- Black or African American8.2% · 216
- Two or more races2.8% · 73
- Hispanic or Latino2.7% · 71
- Asian and Pacific Islander0.5% · 14
- American Indian and Alaska Native0.5% · 14
Timeline
Historical Census data for Hennigan
Hennigan 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
#10,726
National surname rank
Recorded bearers 2,978
+77 bearers (+2.7%)
Per 100,000 1.01
Rank movement Down 526 places
2020
#11,426
National surname rank
Recorded bearers 2,637
-341 bearers (-11.5%)
Per 100,000 0.88
Rank movement Down 700 places
| Year | Rank | Count | Per 100K | Count change | Rank change |
|---|---|---|---|---|---|
| 2000 | #10,200 | 2,901 | 1.08 | First available Census row | First available Census row |
| 2010 | #10,726 | 2,978 | 1.01 | +77 bearers (+2.7%) | Down 526 places |
| 2020 | #11,426 | 2,637 | 0.88 | -341 bearers (-11.5%) | Down 700 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 Hennigan 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 | #10,726 | #11,426 | -6.5% |
| Count | 2,978 | 2,637 | -11.5% |
| Per 100K | 1.01 | 0.88 | -12.6% |
Between the 2010 and 2020 Census, the number of Hennigan bearers went from 2,978 to 2,637 (-11.5% change). The surname moved down 700 positions in the national ranking, going from #10,726 to #11,426.
FAQ
Hennigan surname: questions and answers
How many people in the U.S. have the surname Hennigan?
Name Census estimates that about 3,024 living Americans carry the surname Hennigan. Using the current population baseline, that works out to roughly 1 in 113,345 residents.
How common is Hennigan?
Hennigan ranks #11,426 in the 2020 Census surname tables and is classified on this site as "Rare." The Census recorded the name at a frequency of 0.88 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 2,637 people with the surname Hennigan. That is different from the site's living-bearer estimate (3,024), which projects the surname's present-day count by applying the Census frequency rate to the current U.S. population.
What does 0.88 per 100,000 actually mean?
It is the Census Bureau's normalized frequency measure. A rate of 0.88 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 Hennigan.
Has Hennigan become more or less common over time?
Between 2010 and 2020, the surname Hennigan went from 2,978 recorded bearers to 2,637. That is a decrease of 341 (-11.5%). In the national ranking it fell from #10,726 to #11,426.
What does the Census say about the background of Hennigan?
Among Census respondents with the surname Hennigan, the largest self-reported group is White at 85.3%. The next largest groups are Black (8.2%) and Two or More Races (2.8%). 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 Hennigan in the 2020 Census, accounting for 85.3% (2,249 people in the source table).
What is the full ancestry breakdown?
Hennigan appears across multiple self-reported groups in the Census data. The largest shares in the 2020 file are White (85.3%), Black (8.2%), Two or More Races (2.8%). 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 Hennigan (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 Hennigan mean?
Anglicized form of Irish Ó hÉanacháin, meaning "descendant of Éanachán," a personal name derived from a diminutive of éan, meaning "bird." 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 Hennigan (0.88 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 Hennigan?
For a faster, more casual read, check HowManyOfMe.org — our sister site built around that single question.