2000
#10,004
National surname rank
Recorded bearers 2,972
First available Census row
Per 100,000 1.10
Rare Last name
Sinnott
Derived from the Irish Gaelic "Sinéad," meaning "God is gracious," or from the place name Sionnach, meaning "fox."
According to the 2020 US Census Bureau surname tables, roughly 3,073 Americans carry the last name Sinnott. That puts it at #11,273 in the national surname ranking, appearing at a frequency of 0.90 per 100,000 people (about 1 in 111,537 residents).
This page is the full Name Census profile for the Sinnott 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 Sinnott with 1881 census detail, origin facts and modern UK distribution where available.
Bearers in the US
3.1K
1 in 111,537
Census rank
#11,273
2020 decennial data
Per 100,000
0.9
Frequency rate
Recorded bearers
2.7K
rare in the US
Popularity narrative
The Census Bureau recorded 2,680 bearers of the surname Sinnott in its 2020 decennial surname file. At a rate of 0.90 per 100,000 residents, it holds the 11273rd position in the national surname ranking.
Among Census respondents with the surname Sinnott, the largest self-reported group is White at 91.8%. The next largest groups are Hispanic (3.2%) and Two or More Races (2.5%).
Origin
Meaning and origin of Sinnott
The surname Sinnott has its origins in Ireland, where it was first recorded in the 12th century. It is derived from the Gaelic word "sionnach," meaning "fox," which suggests that the name may have originated as a nickname for someone who was considered cunning or sly.
The earliest recorded instance of the name is found in the Annals of the Four Masters, a chronicle of medieval Irish history compiled in the 17th century. The annals mention a Sinnott family from County Wexford, who were prominent landowners in the area.
During the Norman invasion of Ireland in the 12th century, many Sinnott family members were granted lands in counties Wexford, Waterford, and Kilkenny. Historical records show that in 1192, a man named Adam de Synot was granted lands in Wexford by the Earl of Pembroke.
The variant spelling "Synott" is found in several ancient Irish manuscripts, including the Book of Leinster, a 12th-century literary collection. This spelling suggests that the name may have been pronounced differently in earlier times.
One of the earliest notable figures bearing the name was Walter Sinnott, a 14th-century Bishop of Leighlin who played a significant role in the church's administration in Ireland during his time.
In the 16th century, Sinnott families were prominent landowners in County Wexford, with their ancestral seat located at Ballybrennan. One notable member of the family was Sir John Sinnott (1547-1619), who served as a Member of Parliament and was knighted by King James I.
Another notable figure was Edmond Sinnott (1650-1737), an Irish Catholic priest who was appointed as the Vicar Apostolic of the Diocese of Dublin in 1718. He played a crucial role in the preservation of Catholicism in Ireland during the Penal Laws.
During the Irish Rebellion of 1798, several members of the Sinnott family were actively involved in the struggle for Irish independence. One such figure was John Sinnott (1773-1798), who was executed for his role in the rebellion.
In the 19th century, James Sinnott (1816-1900) was a prominent Irish politician who served as a Member of Parliament for Wexford Borough from 1865 to 1900. He was a strong advocate for Irish Home Rule and played a significant role in Irish politics during his time.
Demographics
Ancestry and ethnicity for Sinnott
Among Census respondents with the surname Sinnott, the largest self-reported group is White at 91.8%. The next largest groups are Hispanic (3.2%) and Two or More Races (2.5%).
The bar chart below shows how Sinnott 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 Sinnott surname at the time of the 2020 Census, not any inherent property of the name itself.
- White91.8% · 2,460
- Hispanic or Latino3.2% · 86
- Two or more races2.5% · 68
- Asian and Pacific Islander1.4% · 38
- Black or African American1.0% · 26
- American Indian and Alaska Native0.1% · 2
Timeline
Historical Census data for Sinnott
Sinnott 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
#10,871
National surname rank
Recorded bearers 2,931
-41 bearers (-1.4%)
Per 100,000 0.99
Rank movement Down 867 places
2020
#11,273
National surname rank
Recorded bearers 2,680
-251 bearers (-8.6%)
Per 100,000 0.90
Rank movement Down 402 places
| Year | Rank | Count | Per 100K | Count change | Rank change |
|---|---|---|---|---|---|
| 2000 | #10,004 | 2,972 | 1.10 | First available Census row | First available Census row |
| 2010 | #10,871 | 2,931 | 0.99 | -41 bearers (-1.4%) | Down 867 places |
| 2020 | #11,273 | 2,680 | 0.90 | -251 bearers (-8.6%) | Down 402 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 Sinnott 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 | #10,871 | #11,273 | -3.7% |
| Count | 2,931 | 2,680 | -8.6% |
| Per 100K | 0.99 | 0.90 | -9.4% |
Between the 2010 and 2020 Census, the number of Sinnott bearers went from 2,931 to 2,680 (-8.6% change). The surname moved down 402 positions in the national ranking, going from #10,871 to #11,273.
FAQ
Sinnott surname: questions and answers
How many people in the U.S. have the surname Sinnott?
Name Census estimates that about 3,073 living Americans carry the surname Sinnott. Using the current population baseline, that works out to roughly 1 in 111,537 residents.
How common is Sinnott?
Sinnott ranks #11,273 in the 2020 Census surname tables and is classified on this site as "Rare." The Census recorded the name at a frequency of 0.90 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 2,680 people with the surname Sinnott. That is different from the site's living-bearer estimate (3,073), which projects the surname's present-day count by applying the Census frequency rate to the current U.S. population.
What does 0.9 per 100,000 actually mean?
It is the Census Bureau's normalized frequency measure. A rate of 0.90 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 Sinnott.
Has Sinnott become more or less common over time?
Between 2010 and 2020, the surname Sinnott went from 2,931 recorded bearers to 2,680. That is a decrease of 251 (-8.6%). In the national ranking it fell from #10,871 to #11,273.
What does the Census say about the background of Sinnott?
Among Census respondents with the surname Sinnott, the largest self-reported group is White at 91.8%. The next largest groups are Hispanic (3.2%) and Two or More Races (2.5%). 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 Sinnott in the 2020 Census, accounting for 91.8% (2,460 people in the source table).
What is the full ancestry breakdown?
Sinnott appears across multiple self-reported groups in the Census data. The largest shares in the 2020 file are White (91.8%), Hispanic (3.2%), Two or More Races (2.5%). 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 Sinnott (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 Sinnott mean?
Derived from the Irish Gaelic "Sinéad," meaning "God is gracious," or from the place name Sionnach, meaning "fox." 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 Sinnott (0.90 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 Sinnott?
Find out how common the surname Sinnott is on our sister site HowManyOfMe.org — a quick modern estimate with the living-bearer count front and centre.