2000
#133,114
National surname rank
Recorded bearers 117
First available Census row
Per 100,000 0.04
Very Rare Last name
Pacilli
An Italian surname indicating someone lived near or on a farm.
According to the 2020 US Census Bureau surname tables, roughly 126 Americans carry the last name Pacilli. That puts it at #149,446 in the national surname ranking, appearing at a frequency of 0.04 per 100,000 people (about 1 in 2,720,273 residents).
This page is the full Name Census profile for the Pacilli 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
126
1 in 2,720,273
Census rank
#149,446
2020 decennial data
Per 100,000
0.0
Frequency rate
Recorded bearers
110
very rare in the US
Popularity narrative
The Census Bureau recorded 110 bearers of the surname Pacilli in its 2020 decennial surname file. At a rate of 0.04 per 100,000 residents, it holds the 149446th position in the national surname ranking.
Among Census respondents with the surname Pacilli, the largest self-reported group is White at 82.7%. The next largest groups are Hispanic (12.7%) and Two or More Races (2.7%).
Origin
Meaning and origin of Pacilli
The surname Pacilli is of Italian origin, tracing its roots back to the regions of Campania and Calabria in southern Italy. The name is believed to have derived from the Latin word "pax," meaning peace or tranquility, combined with the diminutive suffix "-illi." This suggests that the name may have initially been a nickname or descriptive term for someone with a peaceful or tranquil demeanor.
One of the earliest recorded instances of the name Pacilli can be found in historical documents from the 16th century. In 1589, a notary named Girolamo Pacilli was mentioned in records from the city of Naples, indicating the presence of the surname in the Campania region during that time period.
In the 17th century, the Pacilli name appeared in records from the town of Cosenza, located in the Calabria region. A prominent figure bearing this surname was Domenico Pacilli, a scholar and philosopher who lived from 1625 to 1698. His works on ethics and metaphysics were widely acclaimed during his lifetime.
The 18th century saw the emergence of another notable individual with the Pacilli surname, Antonio Pacilli. Born in 1736 in the town of Vibo Valentia, Calabria, he was a renowned painter known for his religious works and portraiture. His paintings can still be found in various churches and museums throughout southern Italy.
Moving into the 19th century, the name Pacilli gained wider recognition with the birth of Giuseppe Pacilli in 1863. A respected lawyer and politician, he served as a member of the Italian Parliament representing the Calabria region from 1892 to 1904.
Another significant figure bearing the Pacilli surname was Francesco Pacilli, born in 1875 in the town of Monteleone di Calabria (now known as Vibo Valentia). He was a renowned physician and researcher who made significant contributions to the study of infectious diseases, particularly malaria. His work helped advance the understanding and treatment of this deadly disease in the early 20th century.
Throughout history, the Pacilli name has been associated with various professions, ranging from scholars and artists to politicians and medical professionals. While its origins can be traced back to southern Italy, the surname has since spread to other regions and even beyond the borders of Italy, carried by descendants of those bearing this distinctive name.
Demographics
Ancestry and ethnicity for Pacilli
Among Census respondents with the surname Pacilli, the largest self-reported group is White at 82.7%. The next largest groups are Hispanic (12.7%) and Two or More Races (2.7%).
The bar chart below shows how Pacilli 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 Pacilli surname at the time of the 2020 Census, not any inherent property of the name itself.
- White82.7% · 91
- Hispanic or Latino12.7% · 14
- Two or more races2.7% · 3
- Asian and Pacific Islander1.8% · 2
Timeline
Historical Census data for Pacilli
Pacilli 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
#147,253
National surname rank
Recorded bearers 112
-5 bearers (-4.3%)
Per 100,000 0.04
Rank movement Down 14,139 places
2020
#149,446
National surname rank
Recorded bearers 110
-2 bearers (-1.8%)
Per 100,000 0.04
Rank movement Down 2,193 places
| Year | Rank | Count | Per 100K | Count change | Rank change |
|---|---|---|---|---|---|
| 2000 | #133,114 | 117 | 0.04 | First available Census row | First available Census row |
| 2010 | #147,253 | 112 | 0.04 | -5 bearers (-4.3%) | Down 14,139 places |
| 2020 | #149,446 | 110 | 0.04 | -2 bearers (-1.8%) | Down 2,193 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 Pacilli 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 | #147,253 | #149,446 | -1.5% |
| Count | 112 | 110 | -1.8% |
| Per 100K | 0.04 | 0.04 | -8.0% |
Between the 2010 and 2020 Census, the number of Pacilli bearers went from 112 to 110 (-1.8% change). The surname moved down 2,193 positions in the national ranking, going from #147,253 to #149,446.
FAQ
Pacilli surname: questions and answers
How many people in the U.S. have the surname Pacilli?
Name Census estimates that about 126 living Americans carry the surname Pacilli. Using the current population baseline, that works out to roughly 1 in 2,720,273 residents.
How common is Pacilli?
Pacilli ranks #149,446 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 110 people with the surname Pacilli. That is different from the site's living-bearer estimate (126), 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 Pacilli.
Has Pacilli become more or less common over time?
Between 2010 and 2020, the surname Pacilli went from 112 recorded bearers to 110. That is a decrease of 2 (-1.8%). In the national ranking it fell from #147,253 to #149,446.
What does the Census say about the background of Pacilli?
Among Census respondents with the surname Pacilli, the largest self-reported group is White at 82.7%. The next largest groups are Hispanic (12.7%) and Two or More Races (2.7%). 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 Pacilli in the 2020 Census, accounting for 82.7% (91 people in the source table).
What is the full ancestry breakdown?
Pacilli appears across multiple self-reported groups in the Census data. The largest shares in the 2020 file are White (82.7%), Hispanic (12.7%), Two or More Races (2.7%). 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 Pacilli (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 Pacilli mean?
An Italian surname indicating someone lived near or on a farm. 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 Pacilli (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 Americans have the surname Pacilli?
For a faster, more casual read, check HowManyOfMe.org — our sister site built around that single question.