2000
#125,639
National surname rank
Recorded bearers 126
First available Census row
Per 100,000 0.05
Very Rare Last name
Kosis
A Greek surname derived from the prefix "cos-" meaning order or ornament.
According to the 2020 US Census Bureau surname tables, roughly 128 Americans carry the last name Kosis. That puts it at #147,954 in the national surname ranking, appearing at a frequency of 0.04 per 100,000 people (about 1 in 2,677,768 residents).
This page is the full Name Census profile for the Kosis 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
128
1 in 2,677,768
Census rank
#147,954
2020 decennial data
Per 100,000
0.0
Frequency rate
Recorded bearers
112
very rare in the US
Popularity narrative
The Census Bureau recorded 112 bearers of the surname Kosis in its 2020 decennial surname file. At a rate of 0.04 per 100,000 residents, it holds the 147954th position in the national surname ranking.
Among Census respondents with the surname Kosis, the largest self-reported group is White at 97.3%. The next largest groups are Two or More Races (1.8%) and Asian/Pacific Islander (0.9%).
Origin
Meaning and origin of Kosis
The surname KOSIS is of Polish origin, tracing its roots back to the 16th century. It is believed to have originated in the region of Silesia, which was historically part of Poland but is now divided between modern-day Poland and the Czech Republic.
One of the earliest known references to the KOSIS name can be found in the records of the town of Kożuchów, located in the Lower Silesian Voivodeship of Poland. In a document dated 1587, a man named Jan KOSIS is mentioned as a landowner in the area. This suggests that the name may have originated as a designation for someone from the village of Kożuchów or a nearby locality.
The surname KOSIS is thought to be derived from the Polish word "koza," which means "goat." It is possible that the name was initially given as a descriptive nickname to someone who tended goats or had some other association with these animals.
In the 17th century, the KOSIS name appears in records from the city of Wrocław (formerly known as Breslau), which was a major center of Polish culture and commerce at the time. A merchant named Jakub KOSIS is mentioned in a trade document from 1632, suggesting that the family had established itself in urban areas by this point.
One notable individual with the KOSIS surname was Franciszek KOSIS (1725-1797), a Polish painter and engraver who was active in the late 18th century. His works, which included religious paintings and portraits, can be found in several churches and museums in Poland.
Another historical figure was Stanisław KOSIS (1803-1872), a Polish writer and translator who was instrumental in popularizing the works of Shakespeare in his native language. He published several acclaimed translations of Shakespeare's plays, including "Hamlet" and "Macbeth."
In the 19th century, the KOSIS name appears in records from various regions of Poland, including the areas around Kraków and Lublin. This suggests that the family had spread across the country by this time.
One prominent person with the KOSIS surname was Kazimierz KOSIS (1857-1931), a Polish engineer and inventor who was instrumental in the development of early radio technology. He held several patents for radio transmitters and receivers, and his work played a significant role in the advancement of wireless communication.
Another individual of note was Maria KOSIS (1879-1962), a Polish educator and advocate for women's rights. She was involved in establishing several schools for girls in Poland and worked tirelessly to promote educational opportunities for women in the early 20th century.
Demographics
Ancestry and ethnicity for Kosis
Among Census respondents with the surname Kosis, the largest self-reported group is White at 97.3%. The next largest groups are Two or More Races (1.8%) and Asian/Pacific Islander (0.9%).
The bar chart below shows how Kosis 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 Kosis surname at the time of the 2020 Census, not any inherent property of the name itself.
- White97.3% · 109
- Two or more races1.8% · 2
- Asian and Pacific Islander0.9% · 1
Timeline
Historical Census data for Kosis
Kosis 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
#140,157
National surname rank
Recorded bearers 119
-7 bearers (-5.6%)
Per 100,000 0.04
Rank movement Down 14,518 places
2020
#147,954
National surname rank
Recorded bearers 112
-7 bearers (-5.9%)
Per 100,000 0.04
Rank movement Down 7,797 places
| Year | Rank | Count | Per 100K | Count change | Rank change |
|---|---|---|---|---|---|
| 2000 | #125,639 | 126 | 0.05 | First available Census row | First available Census row |
| 2010 | #140,157 | 119 | 0.04 | -7 bearers (-5.6%) | Down 14,518 places |
| 2020 | #147,954 | 112 | 0.04 | -7 bearers (-5.9%) | Down 7,797 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 Kosis 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 | #140,157 | #147,954 | -5.6% |
| Count | 119 | 112 | -5.9% |
| Per 100K | 0.04 | 0.04 | -6.3% |
Between the 2010 and 2020 Census, the number of Kosis bearers went from 119 to 112 (-5.9% change). The surname moved down 7,797 positions in the national ranking, going from #140,157 to #147,954.
FAQ
Kosis surname: questions and answers
How many people in the U.S. have the surname Kosis?
Name Census estimates that about 128 living Americans carry the surname Kosis. Using the current population baseline, that works out to roughly 1 in 2,677,768 residents.
How common is Kosis?
Kosis ranks #147,954 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 112 people with the surname Kosis. That is different from the site's living-bearer estimate (128), 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 Kosis.
Has Kosis become more or less common over time?
Between 2010 and 2020, the surname Kosis went from 119 recorded bearers to 112. That is a decrease of 7 (-5.9%). In the national ranking it fell from #140,157 to #147,954.
What does the Census say about the background of Kosis?
Among Census respondents with the surname Kosis, the largest self-reported group is White at 97.3%. The next largest groups are Two or More Races (1.8%) and Asian/Pacific Islander (0.9%). 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 Kosis in the 2020 Census, accounting for 97.3% (109 people in the source table).
What is the full ancestry breakdown?
Kosis appears across multiple self-reported groups in the Census data. The largest shares in the 2020 file are White (97.3%), Two or More Races (1.8%), Asian/Pacific Islander (0.9%). 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 Kosis (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 Kosis mean?
A Greek surname derived from the prefix "cos-" meaning order or ornament. 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 Kosis (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 have the last name Kosis?
If you just want to know how many Americans have the surname Kosis, HowManyOfMe.org gives you the headline number in one glance.