2000
#67,113
National surname rank
Recorded bearers 275
First available Census row
Per 100,000 0.10
Very Rare Last name
Illsley
A locational name derived from a place called Illsley in Berkshire, England.
According to the 2020 US Census Bureau surname tables, roughly 318 Americans carry the last name Illsley. That puts it at #75,111 in the national surname ranking, appearing at a frequency of 0.09 per 100,000 people (about 1 in 1,077,844 residents).
This page is the full Name Census profile for the Illsley 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 Illsley with 1881 census detail, origin facts and modern UK distribution where available.
Bearers in the US
318
1 in 1,077,844
Census rank
#75,111
2020 decennial data
Per 100,000
0.1
Frequency rate
Recorded bearers
277
very rare in the US
Popularity narrative
The Census Bureau recorded 277 bearers of the surname Illsley in its 2020 decennial surname file. At a rate of 0.09 per 100,000 residents, it holds the 75111th position in the national surname ranking.
Among Census respondents with the surname Illsley, the largest self-reported group is White at 91.7%. The next largest groups are Hispanic (4.7%) and Two or More Races (2.5%).
Origin
Meaning and origin of Illsley
The surname Illsley has its origins in England, first appearing in historical records during the medieval period. It is believed to be a locational name, derived from a place name that may have been spelled Illsley or a similar variation. The name likely originated in one of the villages or towns bearing a name resembling Illsley.
One of the earliest documented instances of the name Illsley can be found in the Hundredorum Rolls of 1273, which were records of landholders in various English counties. This suggests that the Illsley family had established roots in England by the 13th century.
In the 14th century, the name appeared in the Poll Tax Returns of Yorkshire in 1379, further solidifying its presence in the region. The spellings "Illesley" and "Illislee" were also recorded during this time, indicating the variations that existed in the spelling of the name.
During the 16th century, the Illsley name was well-established in various parts of England. Notable individuals bearing this surname include John Illsley, a merchant from Bristol who was active in the mid-1500s, and William Illsley, a landowner in Gloucestershire mentioned in the Lay Subsidy Rolls of 1576.
In the 17th century, the Illsley family continued to flourish, with records indicating their presence in counties such as Oxfordshire and Warwickshire. One notable figure from this period was Robert Illsley, a clergyman who served as the Rector of Addington in Buckinghamshire from 1640 until his death in 1670.
Moving into the 18th century, the name Illsley gained prominence in various fields. Thomas Illsley (1693-1762) was a renowned English clockmaker, known for his intricate and highly accurate timepieces. Another notable individual was Richard Illsley (1720-1798), a prominent merchant and landowner in Gloucestershire.
As the centuries progressed, the Illsley surname continued to be represented across various walks of life. In the 19th century, Joseph Illsley (1819-1891) was a respected architect who designed several notable buildings in London, including St. John's Church in Waterloo.
These are just a few examples of the rich history and varied backgrounds associated with the surname Illsley throughout the centuries, reflecting its deep roots in English heritage and the diverse contributions made by those who bore this name.
Demographics
Ancestry and ethnicity for Illsley
Among Census respondents with the surname Illsley, the largest self-reported group is White at 91.7%. The next largest groups are Hispanic (4.7%) and Two or More Races (2.5%).
The bar chart below shows how Illsley 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 Illsley surname at the time of the 2020 Census, not any inherent property of the name itself.
- White91.7% · 254
- Hispanic or Latino4.7% · 13
- Two or more races2.5% · 7
- Black or African American0.4% · 1
- Asian and Pacific Islander0.4% · 1
- American Indian and Alaska Native0.4% · 1
Timeline
Historical Census data for Illsley
Illsley 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
#69,579
National surname rank
Recorded bearers 282
+7 bearers (+2.5%)
Per 100,000 0.10
Rank movement Down 2,466 places
2020
#75,111
National surname rank
Recorded bearers 277
-5 bearers (-1.8%)
Per 100,000 0.09
Rank movement Down 5,532 places
| Year | Rank | Count | Per 100K | Count change | Rank change |
|---|---|---|---|---|---|
| 2000 | #67,113 | 275 | 0.10 | First available Census row | First available Census row |
| 2010 | #69,579 | 282 | 0.10 | +7 bearers (+2.5%) | Down 2,466 places |
| 2020 | #75,111 | 277 | 0.09 | -5 bearers (-1.8%) | Down 5,532 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 Illsley 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 | #69,579 | #75,111 | -8.0% |
| Count | 282 | 277 | -1.8% |
| Per 100K | 0.10 | 0.09 | -7.3% |
Between the 2010 and 2020 Census, the number of Illsley bearers went from 282 to 277 (-1.8% change). The surname moved down 5,532 positions in the national ranking, going from #69,579 to #75,111.
Notable bearers
Famous people with the surname Illsley
FAQ
Illsley surname: questions and answers
How many people in the U.S. have the surname Illsley?
Name Census estimates that about 318 living Americans carry the surname Illsley. Using the current population baseline, that works out to roughly 1 in 1,077,844 residents.
How common is Illsley?
Illsley ranks #75,111 in the 2020 Census surname tables and is classified on this site as "Very Rare." The Census recorded the name at a frequency of 0.09 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 277 people with the surname Illsley. That is different from the site's living-bearer estimate (318), which projects the surname's present-day count by applying the Census frequency rate to the current U.S. population.
What does 0.09 per 100,000 actually mean?
It is the Census Bureau's normalized frequency measure. A rate of 0.09 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 Illsley.
Has Illsley become more or less common over time?
Between 2010 and 2020, the surname Illsley went from 282 recorded bearers to 277. That is a decrease of 5 (-1.8%). In the national ranking it fell from #69,579 to #75,111.
What does the Census say about the background of Illsley?
Among Census respondents with the surname Illsley, the largest self-reported group is White at 91.7%. The next largest groups are Hispanic (4.7%) 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 Illsley in the 2020 Census, accounting for 91.7% (254 people in the source table).
What is the full ancestry breakdown?
Illsley appears across multiple self-reported groups in the Census data. The largest shares in the 2020 file are White (91.7%), Hispanic (4.7%), 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 Illsley (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 Illsley mean?
A locational name derived from a place called Illsley in Berkshire, England. 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 Illsley (0.09 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 Illsley?
For a faster, more casual read, check HowManyOfMe.org — our sister site built around that single question.