2010
#160,975
National surname rank
Recorded bearers 100
First available Census row
Per 100,000 0.03
Very Rare Last name
Sierocki
A Polish surname possibly derived from a word meaning "orphan."
According to the 2020 US Census Bureau surname tables, roughly 116 Americans carry the last name Sierocki. That puts it at #155,270 in the national surname ranking, appearing at a frequency of 0.03 per 100,000 people (about 1 in 2,954,779 residents).
This page is the full Name Census profile for the Sierocki 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
116
1 in 2,954,779
Census rank
#155,270
2020 decennial data
Per 100,000
0.0
Frequency rate
Recorded bearers
101
very rare in the US
Popularity narrative
The Census Bureau recorded 101 bearers of the surname Sierocki in its 2020 decennial surname file. At a rate of 0.03 per 100,000 residents, it holds the 155270th position in the national surname ranking.
Among Census respondents with the surname Sierocki, the largest self-reported group is White at 96.0%. The next largest groups are Hispanic (2.0%) and American Indian/Alaska Native (1.0%).
Origin
Meaning and origin of Sierocki
The surname "SIEROCKI" is of Polish origin, derived from the Polish word "sierota" meaning "orphan." It likely originated in the late medieval period, around the 14th or 15th century, when surnames were becoming more common in Poland.
The name may have originally been given as a descriptive surname to someone who was an orphan or who worked with orphans, perhaps in an orphanage or church-run institution. It could also have been given as a nickname to someone who appeared to be alone or without family.
One of the earliest recorded instances of the name can be found in the records of the town of Krakow, where a certain Maciej Sierocki is mentioned in a document from 1495. There is also a reference to a Jan Sierocki in the records of the town of Poznan from around the same time period.
The name appears to have been particularly concentrated in the central and southern regions of Poland, though it could be found throughout the country. Variations in spelling included "Sieroczki," "Syroczki," and "Szyrocki."
A notable bearer of the name was Piotr Sierocki (1558-1618), a Polish nobleman and military commander who fought in the Polish-Swedish wars of the early 17th century. Another was Kazimierz Sierocki (1756-1827), a Polish mathematician and astronomer who made significant contributions to the field of celestial mechanics.
In the 19th century, Jan Sierocki (1815-1878) was a prominent Polish politician and journalist who advocated for Polish independence from foreign rule. His contemporary, Wincenty Sierocki (1822-1891), was a distinguished painter and artist known for his portraits and religious works.
Toward the end of the 19th century, Franciszek Sierocki (1858-1933) was a notable writer and poet who helped revive interest in Poland's cultural heritage and folklore.
Demographics
Ancestry and ethnicity for Sierocki
Among Census respondents with the surname Sierocki, the largest self-reported group is White at 96.0%. The next largest groups are Hispanic (2.0%) and American Indian/Alaska Native (1.0%).
The bar chart below shows how Sierocki 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 Sierocki surname at the time of the 2020 Census, not any inherent property of the name itself.
- White96.0% · 97
- Hispanic or Latino2.0% · 2
- American Indian and Alaska Native1.0% · 1
- Two or more races1.0% · 1
Timeline
Historical Census data for Sierocki
Sierocki appears in 2 published Census surname files: 2010, 2020. The cards below show how the name's rank and bearer count changed across each release.
2020
#155,270
National surname rank
Recorded bearers 101
+1 bearers (+1.0%)
Per 100,000 0.03
Rank movement Up 5,705 places
| Year | Rank | Count | Per 100K | Count change | Rank change |
|---|---|---|---|---|---|
| 2010 | #160,975 | 100 | 0.03 | First available Census row | First available Census row |
| 2020 | #155,270 | 101 | 0.03 | +1 bearers (+1.0%) | Up 5,705 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 Sierocki 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 | #160,975 | #155,270 | 3.5% |
| Count | 100 | 101 | 1.0% |
| Per 100K | 0.03 | 0.03 | 12.6% |
Between the 2010 and 2020 Census, the number of Sierocki bearers went from 100 to 101 (+1.0% change). The surname moved up 5,705 positions in the national ranking, going from #160,975 to #155,270.
FAQ
Sierocki surname: questions and answers
How many people in the U.S. have the surname Sierocki?
Name Census estimates that about 116 living Americans carry the surname Sierocki. Using the current population baseline, that works out to roughly 1 in 2,954,779 residents.
How common is Sierocki?
Sierocki ranks #155,270 in the 2020 Census surname tables and is classified on this site as "Very Rare." The Census recorded the name at a frequency of 0.03 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 101 people with the surname Sierocki. That is different from the site's living-bearer estimate (116), which projects the surname's present-day count by applying the Census frequency rate to the current U.S. population.
What does 0.03 per 100,000 actually mean?
It is the Census Bureau's normalized frequency measure. A rate of 0.03 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 Sierocki.
Has Sierocki become more or less common over time?
Between 2010 and 2020, the surname Sierocki went from 100 recorded bearers to 101. That is an increase of 1 (+1.0%). In the national ranking it rose from #160,975 to #155,270.
What does the Census say about the background of Sierocki?
Among Census respondents with the surname Sierocki, the largest self-reported group is White at 96.0%. The next largest groups are Hispanic (2.0%) and American Indian/Alaska Native (1.0%). 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 Sierocki in the 2020 Census, accounting for 96.0% (97 people in the source table).
What is the full ancestry breakdown?
Sierocki appears across multiple self-reported groups in the Census data. The largest shares in the 2020 file are White (96.0%), Hispanic (2.0%), American Indian/Alaska Native (1.0%). 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 Sierocki (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 Sierocki mean?
A Polish surname possibly derived from a word meaning "orphan." 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 Sierocki (0.03 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 are called Sierocki?
For a quick modern take, check how common the surname Sierocki is on our sister site HowManyOfMe.org.