2000
#7,806
National surname rank
Recorded bearers 3,929
First available Census row
Per 100,000 1.46
Rare Last name
Seo
A Korean surname derived from the Chinese surname Xiao, meaning "dawn" or "morning."
According to the 2020 US Census Bureau surname tables, roughly 9,050 Americans carry the last name Seo. That puts it at #4,348 in the national surname ranking, appearing at a frequency of 2.64 per 100,000 people (about 1 in 37,873 residents).
This page is the full Name Census profile for the Seo 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
9.1K
1 in 37,873
Census rank
#4,348
2020 decennial data
Per 100,000
2.6
Frequency rate
Recorded bearers
7.9K
rare in the US
Popularity narrative
The Census Bureau recorded 7,892 bearers of the surname Seo in its 2020 decennial surname file. At a rate of 2.64 per 100,000 residents, it holds the 4348th position in the national surname ranking.
Among Census respondents with the surname Seo, the largest self-reported group is Asian/Pacific Islander at 94.8%. The next largest groups are White (2.6%) and Two or More Races (1.4%).
Origin
Meaning and origin of Seo
The surname SEO originated in Korea, where it has been a common family name for centuries. It is derived from the Korean word "seo," which means "west" or "western." This suggests that the name may have originally referred to people who lived in or came from the western regions of the Korean peninsula.
One of the earliest recorded instances of the SEO surname can be found in the Samguk Sagi, a historical record of the Three Kingdoms period in Korea (57 BC - 935 AD). The book mentions a figure named SEO Hui, who lived during the Silla Kingdom in the 7th century AD.
During the Goryeo Dynasty (918-1392), the SEO surname gained prominence as several members of the family held important government positions. One notable figure was SEOGeon (1041-1098), a renowned scholar and poet who served as a high-ranking official during the reign of King Goryeo.
In the Joseon Dynasty (1392-1897), the SEO family continued to play a significant role in Korean society. SEO Jiksu (1631-1695) was a prominent Neo-Confucian scholar and writer, while SEO Sang-don (1552-1618) was a respected military leader and strategist.
Moving into more recent history, SEO Chang-hee (1909-1986) was a prominent South Korean politician and diplomat who served as the country's Prime Minister from 1960 to 1961. Another notable figure was SEO Sang-won (1931-2018), a renowned South Korean writer and novelist who won numerous literary awards throughout his career.
While the SEO surname is most common in Korea, there are also small communities of SEO families in other parts of East Asia, likely descended from Korean immigrants or travelers from centuries past. However, the name remains deeply rooted in Korean culture and history, with its origins tracing back to the ancient kingdoms of the Korean peninsula.
Demographics
Ancestry and ethnicity for Seo
Among Census respondents with the surname Seo, the largest self-reported group is Asian/Pacific Islander at 94.8%. The next largest groups are White (2.6%) and Two or More Races (1.4%).
The bar chart below shows how Seo 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 Seo surname at the time of the 2020 Census, not any inherent property of the name itself.
- Asian and Pacific Islander94.8% · 7,485
- White2.6% · 203
- Two or more races1.4% · 110
- Hispanic or Latino0.7% · 52
- Black or African American0.5% · 41
- American Indian and Alaska Native0.0% · 1
Timeline
Historical Census data for Seo
Seo 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
#4,998
National surname rank
Recorded bearers 7,033
+3,104 bearers (+79.0%)
Per 100,000 2.38
Rank movement Up 2,808 places
2020
#4,348
National surname rank
Recorded bearers 7,892
+859 bearers (+12.2%)
Per 100,000 2.64
Rank movement Up 650 places
| Year | Rank | Count | Per 100K | Count change | Rank change |
|---|---|---|---|---|---|
| 2000 | #7,806 | 3,929 | 1.46 | First available Census row | First available Census row |
| 2010 | #4,998 | 7,033 | 2.38 | +3,104 bearers (+79.0%) | Up 2,808 places |
| 2020 | #4,348 | 7,892 | 2.64 | +859 bearers (+12.2%) | Up 650 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 Seo 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 | #4,998 | #4,348 | 13.0% |
| Count | 7,033 | 7,892 | 12.2% |
| Per 100K | 2.38 | 2.64 | 10.9% |
Between the 2010 and 2020 Census, the number of Seo bearers went from 7,033 to 7,892 (+12.2% change). The surname moved up 650 positions in the national ranking, going from #4,998 to #4,348.
FAQ
Seo surname: questions and answers
How many people in the U.S. have the surname Seo?
Name Census estimates that about 9,050 living Americans carry the surname Seo. Using the current population baseline, that works out to roughly 1 in 37,873 residents.
How common is Seo?
Seo ranks #4,348 in the 2020 Census surname tables and is classified on this site as "Rare." The Census recorded the name at a frequency of 2.64 per 100,000 residents, which is about 3 people out of every 100,000.
How many people with this surname were counted in the Census?
The raw 2020 Census file counted 7,892 people with the surname Seo. That is different from the site's living-bearer estimate (9,050), which projects the surname's present-day count by applying the Census frequency rate to the current U.S. population.
What does 2.64 per 100,000 actually mean?
It is the Census Bureau's normalized frequency measure. A rate of 2.64 per 100,000 means that if you picked a random group of 100,000 U.S. residents, you would expect about 3 of them to have the surname Seo.
Has Seo become more or less common over time?
Between 2010 and 2020, the surname Seo went from 7,033 recorded bearers to 7,892. That is an increase of 859 (+12.2%). In the national ranking it rose from #4,998 to #4,348.
What does the Census say about the background of Seo?
Among Census respondents with the surname Seo, the largest self-reported group is Asian/Pacific Islander at 94.8%. The next largest groups are White (2.6%) and Two or More Races (1.4%). 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?
Asian/Pacific Islander is the largest self-reported group for the surname Seo in the 2020 Census, accounting for 94.8% (7,485 people in the source table).
What is the full ancestry breakdown?
Seo appears across multiple self-reported groups in the Census data. The largest shares in the 2020 file are Asian/Pacific Islander (94.8%), White (2.6%), Two or More Races (1.4%). 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 Seo (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 Seo mean?
A Korean surname derived from the Chinese surname Xiao, meaning "dawn" or "morning." 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 Seo (2.64 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 Seo?
See how many people have the last name Seo on HowManyOfMe.org, our sister site built around that single question.