2000
#10,066
National surname rank
Recorded bearers 2,953
First available Census row
Per 100,000 1.09
Rare Last name
Diez
A Spanish surname derived from the number ten, likely referring to a tenth child or a tithe collector.
According to the 2020 US Census Bureau surname tables, roughly 4,647 Americans carry the last name Diez. That puts it at #7,850 in the national surname ranking, appearing at a frequency of 1.36 per 100,000 people (about 1 in 73,758 residents).
This page is the full Name Census profile for the Diez 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 Diez with 1881 census detail, origin facts and modern UK distribution where available.
Bearers in the US
4.6K
1 in 73,758
Census rank
#7,850
2020 decennial data
Per 100,000
1.4
Frequency rate
Recorded bearers
4.1K
rare in the US
Popularity narrative
The Census Bureau recorded 4,052 bearers of the surname Diez in its 2020 decennial surname file. At a rate of 1.36 per 100,000 residents, it holds the 7850th position in the national surname ranking.
Among Census respondents with the surname Diez, the largest self-reported group is Hispanic at 74.3%. The next largest groups are White (20.7%) and Asian/Pacific Islander (3.3%).
Origin
Meaning and origin of Diez
The surname Diez originated from Spain during the medieval period. It is derived from the Spanish word "diez," which means "ten." This suggests that the name may have initially referred to someone who was the tenth-born child or lived at a house numbered ten.
One of the earliest recorded instances of the Diez surname can be found in the 13th-century records of the Kingdom of Castile, particularly in the province of Burgos. It is believed that the name may have originated from the Castilian town of Diez, located in the Burgos region. However, some historians also suggest that the name could be linked to the Basque word "ditz," meaning "shiny" or "bright."
During the 15th century, the Diez family played a significant role in the Reconquista, the centuries-long campaign to reclaim the Iberian Peninsula from Moorish rule. Juan Diez de Sotomayor (1440-1500), a Spanish military commander, was instrumental in the conquest of Granada, the last Moorish stronghold in Spain.
In the 16th century, the Diez surname gained prominence in the Americas as Spanish conquistadors and settlers ventured into the New World. Gaspar Diez (1510-1570), a Spanish explorer and navigator, accompanied Hernán Cortés on his expedition to Mexico and later served as the governor of Guatemala.
The 17th century saw the rise of several notable figures with the Diez surname. Juan Diez de la Calle (1587-1653) was a Spanish painter renowned for his religious works, while Diego Diez de Aux (1605-1680) was a prominent mathematician and astronomer who contributed to the development of logarithms.
In the 18th century, Manuel Diez de Bonilla (1711-1789) was a Spanish military officer who played a crucial role in the defense of Havana, Cuba, against the British during the Seven Years' War.
The 19th century brought forth Raimundo Diez de Bonilla (1807-1869), a Mexican politician and military leader who served as the governor of several Mexican states and played a significant role in the Mexican-American War.
As the Diez surname spread across different regions, it also underwent variations in spelling, including Diaz, Dias, and Diz. Despite these variations, the surname Diez remains deeply rooted in its Spanish origins and continues to be widely used in Spain, Latin America, and among Hispanic communities worldwide.
Demographics
Ancestry and ethnicity for Diez
Among Census respondents with the surname Diez, the largest self-reported group is Hispanic at 74.3%. The next largest groups are White (20.7%) and Asian/Pacific Islander (3.3%).
The bar chart below shows how Diez 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 Diez surname at the time of the 2020 Census, not any inherent property of the name itself.
- Hispanic or Latino74.3% · 3,009
- White20.7% · 840
- Asian and Pacific Islander3.3% · 135
- Two or more races0.9% · 37
- Black or African American0.7% · 27
- American Indian and Alaska Native0.1% · 4
Timeline
Historical Census data for Diez
Diez 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
#9,293
National surname rank
Recorded bearers 3,502
+549 bearers (+18.6%)
Per 100,000 1.19
Rank movement Up 773 places
2020
#7,850
National surname rank
Recorded bearers 4,052
+550 bearers (+15.7%)
Per 100,000 1.36
Rank movement Up 1,443 places
| Year | Rank | Count | Per 100K | Count change | Rank change |
|---|---|---|---|---|---|
| 2000 | #10,066 | 2,953 | 1.09 | First available Census row | First available Census row |
| 2010 | #9,293 | 3,502 | 1.19 | +549 bearers (+18.6%) | Up 773 places |
| 2020 | #7,850 | 4,052 | 1.36 | +550 bearers (+15.7%) | Up 1,443 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 Diez 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 | #9,293 | #7,850 | 15.5% |
| Count | 3,502 | 4,052 | 15.7% |
| Per 100K | 1.19 | 1.36 | 13.9% |
Between the 2010 and 2020 Census, the number of Diez bearers went from 3,502 to 4,052 (+15.7% change). The surname moved up 1,443 positions in the national ranking, going from #9,293 to #7,850.
FAQ
Diez surname: questions and answers
How many people in the U.S. have the surname Diez?
Name Census estimates that about 4,647 living Americans carry the surname Diez. Using the current population baseline, that works out to roughly 1 in 73,758 residents.
How common is Diez?
Diez ranks #7,850 in the 2020 Census surname tables and is classified on this site as "Rare." The Census recorded the name at a frequency of 1.36 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 4,052 people with the surname Diez. That is different from the site's living-bearer estimate (4,647), which projects the surname's present-day count by applying the Census frequency rate to the current U.S. population.
What does 1.36 per 100,000 actually mean?
It is the Census Bureau's normalized frequency measure. A rate of 1.36 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 Diez.
Has Diez become more or less common over time?
Between 2010 and 2020, the surname Diez went from 3,502 recorded bearers to 4,052. That is an increase of 550 (+15.7%). In the national ranking it rose from #9,293 to #7,850.
What does the Census say about the background of Diez?
Among Census respondents with the surname Diez, the largest self-reported group is Hispanic at 74.3%. The next largest groups are White (20.7%) and Asian/Pacific Islander (3.3%). 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?
Hispanic is the largest self-reported group for the surname Diez in the 2020 Census, accounting for 74.3% (3,009 people in the source table).
What is the full ancestry breakdown?
Diez appears across multiple self-reported groups in the Census data. The largest shares in the 2020 file are Hispanic (74.3%), White (20.7%), Asian/Pacific Islander (3.3%). 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 Diez (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 Diez mean?
A Spanish surname derived from the number ten, likely referring to a tenth child or a tithe collector. 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 Diez (1.36 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 Diez?
HowManyOfMe.org, our sister site, answers that with the living-bearer count in one glance.