2000
#7,435
National surname rank
Recorded bearers 4,129
First available Census row
Per 100,000 1.53
Rare Last name
Mccollough
Anglicized form of the Irish surname Mac Duilligh, meaning "son of Duilligh" (an old Irish personal name of unknown meaning).
According to the 2020 US Census Bureau surname tables, roughly 4,683 Americans carry the last name Mccollough. That puts it at #7,796 in the national surname ranking, appearing at a frequency of 1.37 per 100,000 people (about 1 in 73,191 residents).
This page is the full Name Census profile for the Mccollough 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
4.7K
1 in 73,191
Census rank
#7,796
2020 decennial data
Per 100,000
1.4
Frequency rate
Recorded bearers
4.1K
rare in the US
Popularity narrative
The Census Bureau recorded 4,084 bearers of the surname Mccollough in its 2020 decennial surname file. At a rate of 1.37 per 100,000 residents, it holds the 7796th position in the national surname ranking.
Among Census respondents with the surname Mccollough, the largest self-reported group is White at 69.2%. The next largest groups are Black (22.9%) and Two or More Races (3.8%).
Origin
Meaning and origin of Mccollough
The surname McCollough is of Scottish origin, originating from the Gaelic Mac Olochaidh, meaning "son of the lame one." The name likely emerged in the 13th or 14th century in the Scottish Highlands.
Some early records of the name can be found in the Ragman Rolls of 1296, which documented those who swore allegiance to King Edward I of England. Variants of the spelling included MacCulloch, MacCullough, and MacColluch.
In the 16th century, the McColloughs were a prominent family in the Scottish Borders region, particularly in the area around Dumfries. One notable figure was William McCulloch (c. 1590-1660), a Scottish minister who played a role in the National Covenant and the Glasgow Assembly of 1638.
As the name spread across Scotland and into Ulster, Ireland, it took on various spellings such as McCullough, McCulloch, and McCullagh. In the late 17th century, several McCollough families emigrated to the American colonies, settling in areas like Pennsylvania and Virginia.
One significant figure was Robert McCulloch (1809-1862), a Scottish-American inventor and engineer who developed the first commercially successful cast-iron plow. Another notable individual was Hiram McCullough (1819-1885), a Union Army officer during the American Civil War who later served as the 16th Governor of New Jersey.
Other notable individuals with the surname include Frank McCullough (1885-1952), an American actor and film director during the silent film era, and Angus McCullough (1888-1960), a Scottish-Canadian diplomat who served as the first Canadian ambassador to Egypt and Saudi Arabia.
The spelling "McCollough" is relatively uncommon compared to other variations, but it can be found among families of Scottish and Scots-Irish descent in various parts of the world, particularly in North America and Australia.
Demographics
Ancestry and ethnicity for Mccollough
Among Census respondents with the surname Mccollough, the largest self-reported group is White at 69.2%. The next largest groups are Black (22.9%) and Two or More Races (3.8%).
The bar chart below shows how Mccollough 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 Mccollough surname at the time of the 2020 Census, not any inherent property of the name itself.
- White69.2% · 2,828
- Black or African American22.9% · 935
- Two or more races3.8% · 157
- Hispanic or Latino3.0% · 123
- Asian and Pacific Islander0.6% · 24
- American Indian and Alaska Native0.4% · 17
Timeline
Historical Census data for Mccollough
Mccollough 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
#7,774
National surname rank
Recorded bearers 4,269
+140 bearers (+3.4%)
Per 100,000 1.45
Rank movement Down 339 places
2020
#7,796
National surname rank
Recorded bearers 4,084
-185 bearers (-4.3%)
Per 100,000 1.37
Rank movement Down 22 places
| Year | Rank | Count | Per 100K | Count change | Rank change |
|---|---|---|---|---|---|
| 2000 | #7,435 | 4,129 | 1.53 | First available Census row | First available Census row |
| 2010 | #7,774 | 4,269 | 1.45 | +140 bearers (+3.4%) | Down 339 places |
| 2020 | #7,796 | 4,084 | 1.37 | -185 bearers (-4.3%) | 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 Mccollough 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 | #7,774 | #7,796 | -0.3% |
| Count | 4,269 | 4,084 | -4.3% |
| Per 100K | 1.45 | 1.37 | -5.8% |
Between the 2010 and 2020 Census, the number of Mccollough bearers went from 4,269 to 4,084 (-4.3% change). The surname moved down 22 positions in the national ranking, going from #7,774 to #7,796.
FAQ
Mccollough surname: questions and answers
How many people in the U.S. have the surname Mccollough?
Name Census estimates that about 4,683 living Americans carry the surname Mccollough. Using the current population baseline, that works out to roughly 1 in 73,191 residents.
How common is Mccollough?
Mccollough ranks #7,796 in the 2020 Census surname tables and is classified on this site as "Rare." The Census recorded the name at a frequency of 1.37 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 4,084 people with the surname Mccollough. That is different from the site's living-bearer estimate (4,683), which projects the surname's present-day count by applying the Census frequency rate to the current U.S. population.
What does 1.37 per 100,000 actually mean?
It is the Census Bureau's normalized frequency measure. A rate of 1.37 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 Mccollough.
Has Mccollough become more or less common over time?
Between 2010 and 2020, the surname Mccollough went from 4,269 recorded bearers to 4,084. That is a decrease of 185 (-4.3%). In the national ranking it fell from #7,774 to #7,796.
What does the Census say about the background of Mccollough?
Among Census respondents with the surname Mccollough, the largest self-reported group is White at 69.2%. The next largest groups are Black (22.9%) and Two or More Races (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 Mccollough in the 2020 Census, accounting for 69.2% (2,828 people in the source table).
What is the full ancestry breakdown?
Mccollough appears across multiple self-reported groups in the Census data. The largest shares in the 2020 file are White (69.2%), Black (22.9%), Two or More Races (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 Mccollough (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 Mccollough mean?
Anglicized form of the Irish surname Mac Duilligh, meaning "son of Duilligh" (an old Irish personal name of unknown meaning). 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 Mccollough (1.37 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 last name Mccollough?
Find out how many Americans have the surname Mccollough on our sister site HowManyOfMe.org — a quick modern estimate with the living-bearer count front and centre.