2000
#12,181
National surname rank
Recorded bearers 2,345
First available Census row
Per 100,000 0.87
Rare Last name
Lach
A surname of Polish origin meaning "peasant" or "commoner," derived from the Polish word "lach."
According to the 2020 US Census Bureau surname tables, roughly 2,657 Americans carry the last name Lach. That puts it at #12,722 in the national surname ranking, appearing at a frequency of 0.78 per 100,000 people (about 1 in 129,001 residents).
This page is the full Name Census profile for the Lach 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 Lach with 1881 census detail, origin facts and modern UK distribution where available.
Bearers in the US
2.7K
1 in 129,001
Census rank
#12,722
2020 decennial data
Per 100,000
0.8
Frequency rate
Recorded bearers
2.3K
rare in the US
Popularity narrative
The Census Bureau recorded 2,317 bearers of the surname Lach in its 2020 decennial surname file. At a rate of 0.78 per 100,000 residents, it holds the 12722nd position in the national surname ranking.
Among Census respondents with the surname Lach, the largest self-reported group is White at 80.3%. The next largest groups are Asian/Pacific Islander (14.0%) and Hispanic (2.9%).
Origin
Meaning and origin of Lach
The surname LACH is believed to have originated in Poland. It is a regional name that derived from the Polish word "lach," which referred to a Pole or someone from Poland. The name can be traced back to the 13th century in historical records.
The earliest known bearer of the name was a Polish nobleman named Lach who lived in the late 13th century. He was mentioned in a manuscript from the year 1278 that documented land ownership in the region of Poznan, which was part of the Kingdom of Poland at that time.
In the 14th century, the name appeared in the form "de Lach" in records from the town of Krakow. This Latin variation likely referred to someone from the village of Lach or a person whose family originated from that area.
One of the earliest known people with the surname LACH was Jan Lach, a merchant who lived in the city of Gdansk in the late 15th century. He was mentioned in a trade document from the year 1487 as having conducted business with merchants from the Hanseatic League.
Another notable bearer of the name was Piotr Lach, a Polish soldier who fought in the Polish-Muscovite War of 1609-1618. He was recognized for his bravery in battle and was awarded lands in the region of Podlasie after the war.
In the 17th century, the name LACH appeared in records from the town of Przemysl, which was part of the Polish-Lithuanian Commonwealth at the time. A family by the name of Lach owned a farm in the area, and their descendants continued to live in the region for several generations.
One of the most famous individuals with the surname LACH was Waclaw Lach, a Polish poet and writer who lived from 1664 to 1728. He was known for his satirical works that criticized the nobility and the political system of the Polish-Lithuanian Commonwealth.
During the 19th century, the name LACH was found in various regions of Poland, including the areas of Galicia, Silesia, and the Grand Duchy of Posen. Some notable people with this surname from that period include Franciszek Lach, a Polish painter born in 1820, and Jozef Lach, a Polish composer born in 1856.
Demographics
Ancestry and ethnicity for Lach
Among Census respondents with the surname Lach, the largest self-reported group is White at 80.3%. The next largest groups are Asian/Pacific Islander (14.0%) and Hispanic (2.9%).
The bar chart below shows how Lach 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 Lach surname at the time of the 2020 Census, not any inherent property of the name itself.
- White80.3% · 1,861
- Asian and Pacific Islander14.0% · 324
- Hispanic or Latino2.9% · 67
- Two or more races2.2% · 51
- Black or African American0.5% · 12
- American Indian and Alaska Native0.1% · 2
Timeline
Historical Census data for Lach
Lach 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
#12,362
National surname rank
Recorded bearers 2,515
+170 bearers (+7.2%)
Per 100,000 0.85
Rank movement Down 181 places
2020
#12,722
National surname rank
Recorded bearers 2,317
-198 bearers (-7.9%)
Per 100,000 0.78
Rank movement Down 360 places
| Year | Rank | Count | Per 100K | Count change | Rank change |
|---|---|---|---|---|---|
| 2000 | #12,181 | 2,345 | 0.87 | First available Census row | First available Census row |
| 2010 | #12,362 | 2,515 | 0.85 | +170 bearers (+7.2%) | Down 181 places |
| 2020 | #12,722 | 2,317 | 0.78 | -198 bearers (-7.9%) | Down 360 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 Lach 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 | #12,362 | #12,722 | -2.9% |
| Count | 2,515 | 2,317 | -7.9% |
| Per 100K | 0.85 | 0.78 | -8.8% |
Between the 2010 and 2020 Census, the number of Lach bearers went from 2,515 to 2,317 (-7.9% change). The surname moved down 360 positions in the national ranking, going from #12,362 to #12,722.
FAQ
Lach surname: questions and answers
How many people in the U.S. have the surname Lach?
Name Census estimates that about 2,657 living Americans carry the surname Lach. Using the current population baseline, that works out to roughly 1 in 129,001 residents.
How common is Lach?
Lach ranks #12,722 in the 2020 Census surname tables and is classified on this site as "Rare." The Census recorded the name at a frequency of 0.78 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 2,317 people with the surname Lach. That is different from the site's living-bearer estimate (2,657), which projects the surname's present-day count by applying the Census frequency rate to the current U.S. population.
What does 0.78 per 100,000 actually mean?
It is the Census Bureau's normalized frequency measure. A rate of 0.78 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 Lach.
Has Lach become more or less common over time?
Between 2010 and 2020, the surname Lach went from 2,515 recorded bearers to 2,317. That is a decrease of 198 (-7.9%). In the national ranking it fell from #12,362 to #12,722.
What does the Census say about the background of Lach?
Among Census respondents with the surname Lach, the largest self-reported group is White at 80.3%. The next largest groups are Asian/Pacific Islander (14.0%) and Hispanic (2.9%). 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 Lach in the 2020 Census, accounting for 80.3% (1,861 people in the source table).
What is the full ancestry breakdown?
Lach appears across multiple self-reported groups in the Census data. The largest shares in the 2020 file are White (80.3%), Asian/Pacific Islander (14.0%), Hispanic (2.9%). 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 Lach (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 Lach mean?
A surname of Polish origin meaning "peasant" or "commoner," derived from the Polish word "lach." 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 Lach (0.78 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 Lach?
HowManyOfMe.org, our sister site, answers that with the living-bearer count in one glance.