2000
#144,908
National surname rank
Recorded bearers 105
First available Census row
Per 100,000 0.04
Very Rare Last name
Carstairs
A topographic surname referring to a locality with stairs near a marsh or carr.
According to the 2020 US Census Bureau surname tables, roughly 136 Americans carry the last name Carstairs. That puts it at #142,788 in the national surname ranking, appearing at a frequency of 0.04 per 100,000 people (about 1 in 2,520,252 residents).
This page is the full Name Census profile for the Carstairs 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 Carstairs with 1881 census detail, origin facts and modern UK distribution where available.
Bearers in the US
136
1 in 2,520,252
Census rank
#142,788
2020 decennial data
Per 100,000
0.0
Frequency rate
Recorded bearers
119
very rare in the US
Popularity narrative
The Census Bureau recorded 119 bearers of the surname Carstairs in its 2020 decennial surname file. At a rate of 0.04 per 100,000 residents, it holds the 142788th position in the national surname ranking.
Among Census respondents with the surname Carstairs, the largest self-reported group is White at 85.7%. The next largest groups are Hispanic (10.1%) and Two or More Races (2.5%).
Origin
Meaning and origin of Carstairs
The surname Carstairs has its origins in Scotland, with records indicating its presence as early as the 12th century. It is believed to be a locational name derived from the parish of Carstairs in Lanarkshire, which itself takes its name from the Celtic words 'cathair' meaning 'fort' and 'trev' meaning 'settlement' or 'village'.
One of the earliest known references to the name can be found in the Ragman Rolls of 1296, a collection of feudal homages rendered to King Edward I of England. Here, the name appears as 'de Castres', likely an early variant spelling. Additionally, the name is mentioned in the Exchequer Rolls of Scotland in 1362, where a 'William de Carstaris' is recorded.
In the 16th century, the name appears in various forms such as 'Carstaires', 'Carstayres', and 'Carstares'. One notable bearer of the name from this period was John Carstairs (1623-1686), a Scottish Presbyterian minister and Principal of the University of Edinburgh.
As the centuries progressed, the spelling of the name seems to have solidified into its modern form of 'Carstairs'. One prominent individual with this surname was Joseph Carstairs (1789-1856), a Scottish merchant and philanthropist who made significant contributions to the development of education in Glasgow.
Another notable figure was Robert Carstairs (1819-1900), a Scottish-born civil engineer who played a crucial role in the construction of the Tay Bridge in Scotland. His work on this iconic structure, completed in 1887, was a remarkable engineering feat of the time.
In the literary world, the name Carstairs is associated with Dorothy Carstairs (1892-1974), a British author and illustrator renowned for her children's books, particularly her works featuring the character 'Thomas Traherne'.
While the surname Carstairs may not be among the most common in modern times, its rich history and Scottish roots have left an indelible mark on various fields, from religion and academia to engineering and literature.
Demographics
Ancestry and ethnicity for Carstairs
Among Census respondents with the surname Carstairs, the largest self-reported group is White at 85.7%. The next largest groups are Hispanic (10.1%) and Two or More Races (2.5%).
The bar chart below shows how Carstairs 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 Carstairs surname at the time of the 2020 Census, not any inherent property of the name itself.
- White85.7% · 102
- Hispanic or Latino10.1% · 12
- Two or more races2.5% · 3
- Black or African American1.7% · 2
Timeline
Historical Census data for Carstairs
Carstairs 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
#131,379
National surname rank
Recorded bearers 129
+24 bearers (+22.9%)
Per 100,000 0.04
Rank movement Up 13,529 places
2020
#142,788
National surname rank
Recorded bearers 119
-10 bearers (-7.8%)
Per 100,000 0.04
Rank movement Down 11,409 places
| Year | Rank | Count | Per 100K | Count change | Rank change |
|---|---|---|---|---|---|
| 2000 | #144,908 | 105 | 0.04 | First available Census row | First available Census row |
| 2010 | #131,379 | 129 | 0.04 | +24 bearers (+22.9%) | Up 13,529 places |
| 2020 | #142,788 | 119 | 0.04 | -10 bearers (-7.8%) | Down 11,409 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 Carstairs 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 | #131,379 | #142,788 | -8.7% |
| Count | 129 | 119 | -7.8% |
| Per 100K | 0.04 | 0.04 | -0.5% |
Between the 2010 and 2020 Census, the number of Carstairs bearers went from 129 to 119 (-7.8% change). The surname moved down 11,409 positions in the national ranking, going from #131,379 to #142,788.
FAQ
Carstairs surname: questions and answers
How many people in the U.S. have the surname Carstairs?
Name Census estimates that about 136 living Americans carry the surname Carstairs. Using the current population baseline, that works out to roughly 1 in 2,520,252 residents.
How common is Carstairs?
Carstairs ranks #142,788 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 119 people with the surname Carstairs. That is different from the site's living-bearer estimate (136), 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 Carstairs.
Has Carstairs become more or less common over time?
Between 2010 and 2020, the surname Carstairs went from 129 recorded bearers to 119. That is a decrease of 10 (-7.8%). In the national ranking it fell from #131,379 to #142,788.
What does the Census say about the background of Carstairs?
Among Census respondents with the surname Carstairs, the largest self-reported group is White at 85.7%. The next largest groups are Hispanic (10.1%) and Two or More Races (2.5%). 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 Carstairs in the 2020 Census, accounting for 85.7% (102 people in the source table).
What is the full ancestry breakdown?
Carstairs appears across multiple self-reported groups in the Census data. The largest shares in the 2020 file are White (85.7%), Hispanic (10.1%), Two or More Races (2.5%). 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 Carstairs (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 Carstairs mean?
A topographic surname referring to a locality with stairs near a marsh or carr. 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 Carstairs (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 share the surname Carstairs?
For a faster, more casual read, check HowManyOfMe.org — our sister site built around that single question.