2000
#1,025
National surname rank
Recorded bearers 31,266
First available Census row
Per 100,000 11.59
Uncommon Last name
Costello
An Irish surname derived from the Gaelic "Mac Oisdealbhaigh," meaning "descendant of Oisdealbhach" (a personal name of uncertain origin).
According to the 2020 US Census Bureau surname tables, roughly 35,237 Americans carry the last name Costello. That puts it at #1,121 in the national surname ranking, appearing at a frequency of 10.28 per 100,000 people (about 1 in 9,727 residents).
This page is the full Name Census profile for the Costello 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 Costello with 1881 census detail, origin facts and modern UK distribution where available.
Bearers in the US
35K
1 in 9,727
Census rank
#1,121
2020 decennial data
Per 100,000
10.3
Frequency rate
Recorded bearers
31K
uncommon in the US
Popularity narrative
The Census Bureau recorded 30,728 bearers of the surname Costello in its 2020 decennial surname file. At a rate of 10.28 per 100,000 residents, it holds the 1121st position in the national surname ranking.
Among Census respondents with the surname Costello, the largest self-reported group is White at 87.5%. The next largest groups are Hispanic (7.1%) and Two or More Races (2.8%).
Origin
Meaning and origin of Costello
The surname Costello originated in Ireland and is derived from the Gaelic words "Cos" meaning victory and "Talamh" meaning land or territory. It is an anglicized version of the Irish name "O'Costalaimh" or "O'Costello."
The earliest recorded instances of the surname date back to the 12th century, with the O'Costello clan being based in County Mayo, Ireland. They were a prominent family and held significant influence in the region during the medieval period.
One of the earliest references to the name can be found in the Annals of the Four Masters, a chronicle of medieval Irish history compiled in the 17th century. The text mentions the O'Costello clan and their involvement in various battles and conflicts.
In the 14th century, the surname appears in the Pipe Roll of Cloyne, an administrative record from County Cork. This document lists individuals with the surname Costello living in the area during that time.
Notable historical figures with the surname Costello include:
1. Ambrose Costello (c. 1590 - 1637), an Irish Catholic prelate who served as the Bishop of Clonfert and Kilmacduagh in the early 17th century.
2. Thomas Costello (1766 - 1853), an Irish-born Australian explorer and surveyor who played a significant role in the early exploration of eastern Australia.
3. John Costello (1835 - 1916), an Irish-American politician who served as the 17th Mayor of Syracuse, New York, from 1893 to 1895.
4. John Austin Costello (1891 - 1976), an Irish Fine Gael politician who served as the Taoiseach (Prime Minister) of Ireland from 1948 to 1951.
5. Elvis Costello (born 1954), an English singer-songwriter and record producer, known for his influential contributions to the punk and new wave genres.
While the surname originated in Ireland, it has since spread to other parts of the world due to emigration and diaspora. The name has also undergone various spelling variations over time, such as Costelloe, Costellow, and Costelow.
Demographics
Ancestry and ethnicity for Costello
Among Census respondents with the surname Costello, the largest self-reported group is White at 87.5%. The next largest groups are Hispanic (7.1%) and Two or More Races (2.8%).
The bar chart below shows how Costello 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 Costello surname at the time of the 2020 Census, not any inherent property of the name itself.
- White87.5% · 26,900
- Hispanic or Latino7.1% · 2,177
- Two or more races2.8% · 862
- Black or African American1.5% · 453
- Asian and Pacific Islander0.8% · 254
- American Indian and Alaska Native0.3% · 82
Timeline
Historical Census data for Costello
Costello 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
#1,093
National surname rank
Recorded bearers 32,043
+777 bearers (+2.5%)
Per 100,000 10.86
Rank movement Down 68 places
2020
#1,121
National surname rank
Recorded bearers 30,728
-1,315 bearers (-4.1%)
Per 100,000 10.28
Rank movement Down 28 places
| Year | Rank | Count | Per 100K | Count change | Rank change |
|---|---|---|---|---|---|
| 2000 | #1,025 | 31,266 | 11.59 | First available Census row | First available Census row |
| 2010 | #1,093 | 32,043 | 10.86 | +777 bearers (+2.5%) | Down 68 places |
| 2020 | #1,121 | 30,728 | 10.28 | -1,315 bearers (-4.1%) | Down 28 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 Costello 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 | #1,093 | #1,121 | -2.6% |
| Count | 32,043 | 30,728 | -4.1% |
| Per 100K | 10.86 | 10.28 | -5.3% |
Between the 2010 and 2020 Census, the number of Costello bearers went from 32,043 to 30,728 (-4.1% change). The surname moved down 28 positions in the national ranking, going from #1,093 to #1,121.
Notable bearers
Famous people with the surname Costello
FAQ
Costello surname: questions and answers
How many people in the U.S. have the surname Costello?
Name Census estimates that about 35,237 living Americans carry the surname Costello. Using the current population baseline, that works out to roughly 1 in 9,727 residents.
How common is Costello?
Costello ranks #1,121 in the 2020 Census surname tables and is classified on this site as "Uncommon." The Census recorded the name at a frequency of 10.28 per 100,000 residents, which is about 10 people out of every 100,000.
How many people with this surname were counted in the Census?
The raw 2020 Census file counted 30,728 people with the surname Costello. That is different from the site's living-bearer estimate (35,237), which projects the surname's present-day count by applying the Census frequency rate to the current U.S. population.
What does 10.28 per 100,000 actually mean?
It is the Census Bureau's normalized frequency measure. A rate of 10.28 per 100,000 means that if you picked a random group of 100,000 U.S. residents, you would expect about 10 of them to have the surname Costello.
Has Costello become more or less common over time?
Between 2010 and 2020, the surname Costello went from 32,043 recorded bearers to 30,728. That is a decrease of 1,315 (-4.1%). In the national ranking it fell from #1,093 to #1,121.
What does the Census say about the background of Costello?
Among Census respondents with the surname Costello, the largest self-reported group is White at 87.5%. The next largest groups are Hispanic (7.1%) 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 Costello in the 2020 Census, accounting for 87.5% (26,900 people in the source table).
What is the full ancestry breakdown?
Costello appears across multiple self-reported groups in the Census data. The largest shares in the 2020 file are White (87.5%), Hispanic (7.1%), 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 Costello (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 Costello mean?
An Irish surname derived from the Gaelic "Mac Oisdealbhaigh," meaning "descendant of Oisdealbhach" (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 Costello (10.28 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 Costello?
Want to know how many people are called Costello? HowManyOfMe.org, our sister site, puts the living-bearer count front and centre.