2000
#194
National surname rank
Recorded bearers 133,254
First available Census row
Per 100,000 49.40
Common Last name
Castro
A locational surname referring to someone who lived near a castle, fortress, or fortified building.
According to the 2020 US Census Bureau surname tables, roughly 215,182 Americans carry the last name Castro. That puts it at #130 in the national surname ranking, appearing at a frequency of 62.78 per 100,000 people (about 1 in 1,593 residents).
This page is the full Name Census profile for the Castro 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 Castro with 1881 census detail, origin facts and modern UK distribution where available.
Bearers in the US
215K
1 in 1,593
Census rank
#130
2020 decennial data
Per 100,000
62.8
Frequency rate
Recorded bearers
188K
common in the US
Popularity narrative
The Census Bureau recorded 187,649 bearers of the surname Castro in its 2020 decennial surname file. At a rate of 62.78 per 100,000 residents, it holds the 130th position in the national surname ranking.
Among Census respondents with the surname Castro, the largest self-reported group is Hispanic at 86.8%. The next largest groups are White (7.2%) and Asian/Pacific Islander (4.2%).
Origin
Meaning and origin of Castro
The surname Castro is of Spanish origin, derived from the Latin word "castrum," meaning "fortified place" or "castle." It likely arose during the period of the Reconquista, the centuries-long struggle between Christian and Moorish forces in the Iberian Peninsula.
The name is thought to have originated in the northern regions of Spain, particularly in Galicia and Asturias, where many fortified settlements and castles were established during the Reconquista. The earliest recorded instances of the name Castro can be found in medieval documents and charters from these areas.
One of the earliest known bearers of the name was Rodrigo Castro, a nobleman and military commander who fought against the Moors in the 12th century. Another notable figure was Pedro Fernández de Castro, a 13th-century nobleman and military leader who played a pivotal role in the conquest of Seville.
The name Castro is also associated with several place names in Spain, such as Castro Urdiales in Cantabria, Castro Caldelas in Galicia, and Castro del Río in Andalusia. These place names likely influenced the adoption of the surname by residents of these areas.
Throughout history, there have been several prominent individuals with the surname Castro. One of the most famous was Fidel Castro, the former revolutionary leader and President of Cuba (1926-2016). Another notable figure was Américo Castro (1885-1972), a Spanish scholar and philosopher who made significant contributions to the study of Spanish literature and culture.
Other notable individuals with the surname Castro include:
1. Cipriano Castro (1859-1924), a Venezuelan military officer and President of Venezuela from 1899 to 1908.
2. Inés de Castro (c. 1325-1355), a Galician noblewoman and tragic figure in Portuguese history, whose love story with King Pedro I of Portugal has been widely romanticized.
3. José María Castro (1892-1964), a Mexican painter and muralist, known for his depictions of indigenous Mexican culture.
4. Rosalía de Castro (1837-1885), a Galician romantic poet and novelist, considered one of the most significant figures in Galician literature.
The surname Castro has a rich history rooted in the Iberian Peninsula, tracing its origins back to the medieval period and the struggle against Moorish rule. It has been borne by many notable individuals throughout history, reflecting its enduring presence in Spanish-speaking cultures.
Demographics
Ancestry and ethnicity for Castro
Among Census respondents with the surname Castro, the largest self-reported group is Hispanic at 86.8%. The next largest groups are White (7.2%) and Asian/Pacific Islander (4.2%).
The bar chart below shows how Castro 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 Castro surname at the time of the 2020 Census, not any inherent property of the name itself.
- Hispanic or Latino86.8% · 162,895
- White7.2% · 13,534
- Asian and Pacific Islander4.2% · 7,936
- Two or more races0.8% · 1,411
- Black or African American0.7% · 1,391
- American Indian and Alaska Native0.3% · 482
Timeline
Historical Census data for Castro
Castro 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
#138
National surname rank
Recorded bearers 184,134
+50,880 bearers (+38.2%)
Per 100,000 62.42
Rank movement Up 56 places
2020
#130
National surname rank
Recorded bearers 187,649
+3,515 bearers (+1.9%)
Per 100,000 62.78
Rank movement Up 8 places
| Year | Rank | Count | Per 100K | Count change | Rank change |
|---|---|---|---|---|---|
| 2000 | #194 | 133,254 | 49.40 | First available Census row | First available Census row |
| 2010 | #138 | 184,134 | 62.42 | +50,880 bearers (+38.2%) | Up 56 places |
| 2020 | #130 | 187,649 | 62.78 | +3,515 bearers (+1.9%) | Up 8 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 Castro 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 | #138 | #130 | 5.8% |
| Count | 184,134 | 187,649 | 1.9% |
| Per 100K | 62.42 | 62.78 | 0.6% |
Between the 2010 and 2020 Census, the number of Castro bearers went from 184,134 to 187,649 (+1.9% change). The surname moved up 8 positions in the national ranking, going from #138 to #130.
Notable bearers
Famous people with the surname Castro
FAQ
Castro surname: questions and answers
How many people in the U.S. have the surname Castro?
Name Census estimates that about 215,182 living Americans carry the surname Castro. Using the current population baseline, that works out to roughly 1 in 1,593 residents.
How common is Castro?
Castro ranks #130 in the 2020 Census surname tables and is classified on this site as "Common." The Census recorded the name at a frequency of 62.78 per 100,000 residents, which is about 63 people out of every 100,000.
How many people with this surname were counted in the Census?
The raw 2020 Census file counted 187,649 people with the surname Castro. That is different from the site's living-bearer estimate (215,182), which projects the surname's present-day count by applying the Census frequency rate to the current U.S. population.
What does 62.78 per 100,000 actually mean?
It is the Census Bureau's normalized frequency measure. A rate of 62.78 per 100,000 means that if you picked a random group of 100,000 U.S. residents, you would expect about 63 of them to have the surname Castro.
Has Castro become more or less common over time?
Between 2010 and 2020, the surname Castro went from 184,134 recorded bearers to 187,649. That is an increase of 3,515 (+1.9%). In the national ranking it rose from #138 to #130.
What does the Census say about the background of Castro?
Among Census respondents with the surname Castro, the largest self-reported group is Hispanic at 86.8%. The next largest groups are White (7.2%) and Asian/Pacific Islander (4.2%). 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?
Hispanic is the largest self-reported group for the surname Castro in the 2020 Census, accounting for 86.8% (162,895 people in the source table).
What is the full ancestry breakdown?
Castro appears across multiple self-reported groups in the Census data. The largest shares in the 2020 file are Hispanic (86.8%), White (7.2%), Asian/Pacific Islander (4.2%). 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 Castro (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 Castro mean?
A locational surname referring to someone who lived near a castle, fortress, or fortified building. 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 Castro (62.78 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 Castro?
For a quick modern estimate, our sister site HowManyOfMe.org answers that in one glance, with the living-bearer count front and centre.