2000
#11,428
National surname rank
Recorded bearers 2,530
First available Census row
Per 100,000 0.94
Rare Last name
Sedlacek
A Czech occupational surname referring to a peasant farmer or village mayor.
According to the 2020 US Census Bureau surname tables, roughly 2,821 Americans carry the last name Sedlacek. That puts it at #12,096 in the national surname ranking, appearing at a frequency of 0.82 per 100,000 people (about 1 in 121,501 residents).
This page is the full Name Census profile for the Sedlacek 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
2.8K
1 in 121,501
Census rank
#12,096
2020 decennial data
Per 100,000
0.8
Frequency rate
Recorded bearers
2.5K
rare in the US
Popularity narrative
The Census Bureau recorded 2,460 bearers of the surname Sedlacek in its 2020 decennial surname file. At a rate of 0.82 per 100,000 residents, it holds the 12096th position in the national surname ranking.
Among Census respondents with the surname Sedlacek, the largest self-reported group is White at 93.5%. The next largest groups are Two or More Races (2.8%) and Hispanic (2.6%).
Origin
Meaning and origin of Sedlacek
The surname "SEDLACEK" originated in the Czech Republic and Slovakia during the medieval period. It is derived from the Czech word "sedlák," which means "farmer" or "peasant." The name is a diminutive form, with the suffix "-ek" added, meaning "little farmer" or "small peasant."
The earliest recorded instances of the name date back to the 14th century, appearing in various records and manuscripts from the Czech lands. One of the earliest known bearers was Jan Sedlacek, a farmer from the village of Rataje nad Sazavou, who was mentioned in a land registry document from 1372.
The name was likely associated with individuals who worked as farmers or came from rural areas. In those times, surnames were often derived from occupations, locations, or physical characteristics. The prevalence of the name Sedlacek suggests a strong connection to agricultural communities in the Czech and Slovak regions.
One notable figure with the surname Sedlacek was Václav Sedlacek, a Czech historian and writer who lived from 1785 to 1851. He authored several books on Czech history and culture, including "Hospodářské dějiny českých zemí" (Economic History of the Czech Lands) and "Hrady a zámky v Čechách" (Castles and Palaces in Bohemia).
Another prominent bearer of the name was Jaroslav Sedlacek, a Czech chess player and International Master born in 1929. He won several national championships and represented Czechoslovakia in numerous international tournaments during the 1950s and 1960s.
In the 16th century, the name Sedlacek appeared in various forms, such as "Ssedlaczek" or "Ssedlacziek," reflecting the spelling variations common in historical records. Some early bearers of the name were associated with specific locations, such as the village of Sedlačkov or the town of Sedlec.
Variations of the name can also be found in other Slavic languages, such as the Polish surname "Siedziak" or the Slovak surname "Sedliak," which share similar linguistic roots and meanings related to farming or rural life.
Overall, the surname Sedlacek has a rich history rooted in the agricultural traditions of the Czech and Slovak regions, with its origins dating back to the medieval era and several notable individuals bearing this name throughout the centuries.
Demographics
Ancestry and ethnicity for Sedlacek
Among Census respondents with the surname Sedlacek, the largest self-reported group is White at 93.5%. The next largest groups are Two or More Races (2.8%) and Hispanic (2.6%).
The bar chart below shows how Sedlacek 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 Sedlacek surname at the time of the 2020 Census, not any inherent property of the name itself.
- White93.5% · 2,299
- Two or more races2.8% · 69
- Hispanic or Latino2.6% · 63
- Asian and Pacific Islander0.8% · 20
- American Indian and Alaska Native0.2% · 6
- Black or African American0.1% · 3
Timeline
Historical Census data for Sedlacek
Sedlacek 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
#12,473
National surname rank
Recorded bearers 2,489
-41 bearers (-1.6%)
Per 100,000 0.84
Rank movement Down 1,045 places
2020
#12,096
National surname rank
Recorded bearers 2,460
-29 bearers (-1.2%)
Per 100,000 0.82
Rank movement Up 377 places
| Year | Rank | Count | Per 100K | Count change | Rank change |
|---|---|---|---|---|---|
| 2000 | #11,428 | 2,530 | 0.94 | First available Census row | First available Census row |
| 2010 | #12,473 | 2,489 | 0.84 | -41 bearers (-1.6%) | Down 1,045 places |
| 2020 | #12,096 | 2,460 | 0.82 | -29 bearers (-1.2%) | Up 377 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 Sedlacek 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 | #12,473 | #12,096 | 3.0% |
| Count | 2,489 | 2,460 | -1.2% |
| Per 100K | 0.84 | 0.82 | -2.0% |
Between the 2010 and 2020 Census, the number of Sedlacek bearers went from 2,489 to 2,460 (-1.2% change). The surname moved up 377 positions in the national ranking, going from #12,473 to #12,096.
FAQ
Sedlacek surname: questions and answers
How many people in the U.S. have the surname Sedlacek?
Name Census estimates that about 2,821 living Americans carry the surname Sedlacek. Using the current population baseline, that works out to roughly 1 in 121,501 residents.
How common is Sedlacek?
Sedlacek ranks #12,096 in the 2020 Census surname tables and is classified on this site as "Rare." The Census recorded the name at a frequency of 0.82 per 100,000 residents, which is about 1 people out of every 100,000.
How many people with this surname were counted in the Census?
The raw 2020 Census file counted 2,460 people with the surname Sedlacek. That is different from the site's living-bearer estimate (2,821), which projects the surname's present-day count by applying the Census frequency rate to the current U.S. population.
What does 0.82 per 100,000 actually mean?
It is the Census Bureau's normalized frequency measure. A rate of 0.82 per 100,000 means that if you picked a random group of 100,000 U.S. residents, you would expect about 1 of them to have the surname Sedlacek.
Has Sedlacek become more or less common over time?
Between 2010 and 2020, the surname Sedlacek went from 2,489 recorded bearers to 2,460. That is a decrease of 29 (-1.2%). In the national ranking it rose from #12,473 to #12,096.
What does the Census say about the background of Sedlacek?
Among Census respondents with the surname Sedlacek, the largest self-reported group is White at 93.5%. The next largest groups are Two or More Races (2.8%) and Hispanic (2.6%). 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 Sedlacek in the 2020 Census, accounting for 93.5% (2,299 people in the source table).
What is the full ancestry breakdown?
Sedlacek appears across multiple self-reported groups in the Census data. The largest shares in the 2020 file are White (93.5%), Two or More Races (2.8%), Hispanic (2.6%). 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 Sedlacek (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 Sedlacek mean?
A Czech occupational surname referring to a peasant farmer or village mayor. 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 Sedlacek (0.82 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 surname Sedlacek?
HowManyOfMe.org, our sister site, answers that with the living-bearer count in one glance.