2000
#5,738
National surname rank
Recorded bearers 5,528
First available Census row
Per 100,000 2.05
Rare Last name
Lally
Anglicized form of the Irish surname Ó Leallaigh, meaning "descendant of Leallach," a personal name of uncertain origin.
According to the 2020 US Census Bureau surname tables, roughly 6,432 Americans carry the last name Lally. That puts it at #5,923 in the national surname ranking, appearing at a frequency of 1.88 per 100,000 people (about 1 in 53,289 residents).
This page is the full Name Census profile for the Lally 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 Lally with 1881 census detail, origin facts and modern UK distribution where available.
Bearers in the US
6.4K
1 in 53,289
Census rank
#5,923
2020 decennial data
Per 100,000
1.9
Frequency rate
Recorded bearers
5.6K
rare in the US
Popularity narrative
The Census Bureau recorded 5,609 bearers of the surname Lally in its 2020 decennial surname file. At a rate of 1.88 per 100,000 residents, it holds the 5923rd position in the national surname ranking.
Among Census respondents with the surname Lally, the largest self-reported group is White at 88.0%. The next largest groups are Asian/Pacific Islander (5.2%) and Hispanic (3.4%).
Origin
Meaning and origin of Lally
The surname Lally is believed to have originated in Ireland. It is thought to be an anglicized version of the Irish Gaelic name Ó Mulláilí, which means "descendant of Mulláile". The name Mulláile is a diminutive form of the personal name Muál, derived from the Old Irish word "mul" meaning "chief" or "leader".
The earliest recorded instances of the surname Lally can be traced back to County Sligo, Ireland in the 16th century. Historical records show that the Lallys were a prominent family in the area, holding lands and positions of authority. One notable member of the family was Turlough Lally, who served as a colonel in the Irish Confederate Wars of the 1640s.
During the 17th century, many members of the Lally family were forced to leave Ireland due to the Cromwellian conquest and the subsequent Penal Laws against Catholics. Some Lallys settled in France, where they found employment in the French military. One of the most famous Lallys was Thomas Arthur, Count Lally (1702-1766), who served as a French general and was the commander-in-chief of the French forces in India during the Seven Years' War.
Another notable Lally was Patrick Lally (1738-1789), an Irish Jacobite who fought for the French in the American Revolutionary War. He was captured by the British and later executed for his role in the conflict.
In the 19th century, the Lally surname began to spread beyond Ireland and France as members of the family immigrated to other parts of the world. One prominent figure was James Lally (1828-1897), an Irish-born Australian politician and businessman who served as the Mayor of Melbourne from 1889 to 1891.
Other notable individuals with the surname Lally include John Lally (1929-2018), an American actor best known for his role in the television series "The Untouchables", and Evelyn Lally (1909-1998), an English writer and artist who was a member of the Bloomsbury Group.
Demographics
Ancestry and ethnicity for Lally
Among Census respondents with the surname Lally, the largest self-reported group is White at 88.0%. The next largest groups are Asian/Pacific Islander (5.2%) and Hispanic (3.4%).
The bar chart below shows how Lally 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 Lally surname at the time of the 2020 Census, not any inherent property of the name itself.
- White88.0% · 4,934
- Asian and Pacific Islander5.2% · 292
- Hispanic or Latino3.4% · 188
- Two or more races2.4% · 135
- Black or African American0.9% · 49
- American Indian and Alaska Native0.2% · 11
Timeline
Historical Census data for Lally
Lally 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
#5,931
National surname rank
Recorded bearers 5,808
+280 bearers (+5.1%)
Per 100,000 1.97
Rank movement Down 193 places
2020
#5,923
National surname rank
Recorded bearers 5,609
-199 bearers (-3.4%)
Per 100,000 1.88
Rank movement Up 8 places
| Year | Rank | Count | Per 100K | Count change | Rank change |
|---|---|---|---|---|---|
| 2000 | #5,738 | 5,528 | 2.05 | First available Census row | First available Census row |
| 2010 | #5,931 | 5,808 | 1.97 | +280 bearers (+5.1%) | Down 193 places |
| 2020 | #5,923 | 5,609 | 1.88 | -199 bearers (-3.4%) | Up 8 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 Lally 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 | #5,931 | #5,923 | 0.1% |
| Count | 5,808 | 5,609 | -3.4% |
| Per 100K | 1.97 | 1.88 | -4.7% |
Between the 2010 and 2020 Census, the number of Lally bearers went from 5,808 to 5,609 (-3.4% change). The surname moved up 8 positions in the national ranking, going from #5,931 to #5,923.
FAQ
Lally surname: questions and answers
How many people in the U.S. have the surname Lally?
Name Census estimates that about 6,432 living Americans carry the surname Lally. Using the current population baseline, that works out to roughly 1 in 53,289 residents.
How common is Lally?
Lally ranks #5,923 in the 2020 Census surname tables and is classified on this site as "Rare." The Census recorded the name at a frequency of 1.88 per 100,000 residents, which is about 2 people out of every 100,000.
How many people with this surname were counted in the Census?
The raw 2020 Census file counted 5,609 people with the surname Lally. That is different from the site's living-bearer estimate (6,432), which projects the surname's present-day count by applying the Census frequency rate to the current U.S. population.
What does 1.88 per 100,000 actually mean?
It is the Census Bureau's normalized frequency measure. A rate of 1.88 per 100,000 means that if you picked a random group of 100,000 U.S. residents, you would expect about 2 of them to have the surname Lally.
Has Lally become more or less common over time?
Between 2010 and 2020, the surname Lally went from 5,808 recorded bearers to 5,609. That is a decrease of 199 (-3.4%). In the national ranking it rose from #5,931 to #5,923.
What does the Census say about the background of Lally?
Among Census respondents with the surname Lally, the largest self-reported group is White at 88.0%. The next largest groups are Asian/Pacific Islander (5.2%) and Hispanic (3.4%). 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 Lally in the 2020 Census, accounting for 88.0% (4,934 people in the source table).
What is the full ancestry breakdown?
Lally appears across multiple self-reported groups in the Census data. The largest shares in the 2020 file are White (88.0%), Asian/Pacific Islander (5.2%), Hispanic (3.4%). 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 Lally (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 Lally mean?
Anglicized form of the Irish surname Ó Leallaigh, meaning "descendant of Leallach," a personal name of uncertain origin. 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 Lally (1.88 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 Lally?
HowManyOfMe.org, our sister site, answers that with the living-bearer count in one glance.