2000
#1,542
National surname rank
Recorded bearers 21,340
First available Census row
Per 100,000 7.91
Uncommon Last name
Mcdonough
Anglicized form of the Irish surname Mac Donnchadha, meaning "son of Donnchadh" (derived from Irish words meaning "brown" and "warrior").
According to the 2020 US Census Bureau surname tables, roughly 24,087 Americans carry the last name Mcdonough. That puts it at #1,677 in the national surname ranking, appearing at a frequency of 7.03 per 100,000 people (about 1 in 14,230 residents).
This page is the full Name Census profile for the Mcdonough 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 Mcdonough with 1881 census detail, origin facts and modern UK distribution where available.
Bearers in the US
24K
1 in 14,230
Census rank
#1,677
2020 decennial data
Per 100,000
7.0
Frequency rate
Recorded bearers
21K
uncommon in the US
Popularity narrative
The Census Bureau recorded 21,005 bearers of the surname Mcdonough in its 2020 decennial surname file. At a rate of 7.03 per 100,000 residents, it holds the 1677th position in the national surname ranking.
Among Census respondents with the surname Mcdonough, the largest self-reported group is White at 92.9%. The next largest groups are Hispanic (3.2%) and Two or More Races (2.4%).
Origin
Meaning and origin of Mcdonough
The surname McDonough is of Irish origin, derived from the Gaelic Mac Donnchadha, meaning "son of Donnchadh." Donnchadh was an old Irish personal name composed of the elements "donn" (brown) and "cath" (battle), suggesting a warrior of brown complexion. The McDonough name emerged in the 12th century and was concentrated in counties Galway, Mayo, and Sligo in the western province of Connacht.
Historical records mention the McDonough clan as a prominent sept (sub-division) of the larger Ó Conchobhair (O'Conor) dynasty that ruled over the Kingdom of Connacht. The earliest documented instance of the name appears in the Annals of the Four Masters, which chronicle the death of Tomaltach Mac Donnchadha, a chief of Tír Oilill, in the year 1225.
In the 16th century, the McDonough family gained prominence in County Sligo, where they held extensive lands around the baronies of Leyny and Corran. One notable figure was Myles McDonough, who served as the Archbishop of Armagh from 1512 to 1528. Another influential member was Turlough McDonough, a captain in the Irish Confederate Wars of the 1640s, who fought against the English Parliamentarian forces.
During the Cromwellian conquest of Ireland in the 1650s, many McDonough families were dispossessed of their ancestral lands and forced into exile or transplanted to the province of Connacht. Some found refuge in continental Europe, particularly in Spain and France, where they joined the Irish Brigades in the service of Catholic monarchs.
The McDonough name can also be traced to several prominent figures in the United States. One of the earliest was Thomas McDonough (1768-1825), a renowned naval officer who achieved victory in the Battle of Lake Champlain during the War of 1812. Another notable American was Commodore John McDonough (1799-1891), who served as a naval commander and later as a US Representative from Maryland.
In the literary realm, the name is associated with Randall McDonough (1828-1894), an Irish-American poet and journalist who wrote extensively about the Irish experience in America. Additionally, John McDonough (1876-1933) was a prominent American businessman and co-founder of the McDonough Company, one of the largest construction firms in the early 20th century.
Demographics
Ancestry and ethnicity for Mcdonough
Among Census respondents with the surname Mcdonough, the largest self-reported group is White at 92.9%. The next largest groups are Hispanic (3.2%) and Two or More Races (2.4%).
The bar chart below shows how Mcdonough 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 Mcdonough surname at the time of the 2020 Census, not any inherent property of the name itself.
- White92.9% · 19,512
- Hispanic or Latino3.2% · 677
- Two or more races2.4% · 510
- Asian and Pacific Islander0.7% · 155
- Black or African American0.5% · 104
- American Indian and Alaska Native0.2% · 47
Timeline
Historical Census data for Mcdonough
Mcdonough 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
#1,655
National surname rank
Recorded bearers 21,739
+399 bearers (+1.9%)
Per 100,000 7.37
Rank movement Down 113 places
2020
#1,677
National surname rank
Recorded bearers 21,005
-734 bearers (-3.4%)
Per 100,000 7.03
Rank movement Down 22 places
| Year | Rank | Count | Per 100K | Count change | Rank change |
|---|---|---|---|---|---|
| 2000 | #1,542 | 21,340 | 7.91 | First available Census row | First available Census row |
| 2010 | #1,655 | 21,739 | 7.37 | +399 bearers (+1.9%) | Down 113 places |
| 2020 | #1,677 | 21,005 | 7.03 | -734 bearers (-3.4%) | Down 22 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 Mcdonough 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 | #1,655 | #1,677 | -1.3% |
| Count | 21,739 | 21,005 | -3.4% |
| Per 100K | 7.37 | 7.03 | -4.6% |
Between the 2010 and 2020 Census, the number of Mcdonough bearers went from 21,739 to 21,005 (-3.4% change). The surname moved down 22 positions in the national ranking, going from #1,655 to #1,677.
FAQ
Mcdonough surname: questions and answers
How many people in the U.S. have the surname Mcdonough?
Name Census estimates that about 24,087 living Americans carry the surname Mcdonough. Using the current population baseline, that works out to roughly 1 in 14,230 residents.
How common is Mcdonough?
Mcdonough ranks #1,677 in the 2020 Census surname tables and is classified on this site as "Uncommon." The Census recorded the name at a frequency of 7.03 per 100,000 residents, which is about 7 people out of every 100,000.
How many people with this surname were counted in the Census?
The raw 2020 Census file counted 21,005 people with the surname Mcdonough. That is different from the site's living-bearer estimate (24,087), which projects the surname's present-day count by applying the Census frequency rate to the current U.S. population.
What does 7.03 per 100,000 actually mean?
It is the Census Bureau's normalized frequency measure. A rate of 7.03 per 100,000 means that if you picked a random group of 100,000 U.S. residents, you would expect about 7 of them to have the surname Mcdonough.
Has Mcdonough become more or less common over time?
Between 2010 and 2020, the surname Mcdonough went from 21,739 recorded bearers to 21,005. That is a decrease of 734 (-3.4%). In the national ranking it fell from #1,655 to #1,677.
What does the Census say about the background of Mcdonough?
Among Census respondents with the surname Mcdonough, the largest self-reported group is White at 92.9%. The next largest groups are Hispanic (3.2%) and Two or More Races (2.4%). 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 Mcdonough in the 2020 Census, accounting for 92.9% (19,512 people in the source table).
What is the full ancestry breakdown?
Mcdonough appears across multiple self-reported groups in the Census data. The largest shares in the 2020 file are White (92.9%), Hispanic (3.2%), Two or More Races (2.4%). 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 Mcdonough (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 Mcdonough mean?
Anglicized form of the Irish surname Mac Donnchadha, meaning "son of Donnchadh" (derived from Irish words meaning "brown" and "warrior"). 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 Mcdonough (7.03 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 Mcdonough?
For a quick modern estimate, our sister site HowManyOfMe.org answers that in one glance, with the living-bearer count front and centre.