2000
#73
National surname rank
Recorded bearers 251,772
First available Census row
Per 100,000 93.33
Common Last name
Diaz
A Spanish patronymic surname derived from the given name Diego, meaning "supplanter" or "replacing."
According to the 2020 US Census Bureau surname tables, roughly 409,278 Americans carry the last name Diaz. That puts it at #52 in the national surname ranking, appearing at a frequency of 119.41 per 100,000 people (about 1 in 837 residents).
This page is the full Name Census profile for the Diaz 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 Diaz with 1881 census detail, origin facts and modern UK distribution where available.
Bearers in the US
409K
1 in 837
Census rank
#52
2020 decennial data
Per 100,000
119.4
Frequency rate
Recorded bearers
357K
common in the US
Popularity narrative
The Census Bureau recorded 356,910 bearers of the surname Diaz in its 2020 decennial surname file. At a rate of 119.41 per 100,000 residents, it holds the 52nd position in the national surname ranking.
Among Census respondents with the surname Diaz, the largest self-reported group is Hispanic at 91.9%. The next largest groups are White (5.4%) and Asian/Pacific Islander (1.3%).
Origin
Meaning and origin of Diaz
The surname Diaz originated in Spain and is of Spanish/Iberian origin. It derives from the personal name Dias, which was a medieval Spanish form of the Roman name Didacus. Dias or Diaz ultimately traces back to the Greek name Didakos, meaning "instructed" or "taught".
Diaz is a patronymic surname, meaning it was originally formed by adding the suffix "-ez" (meaning "son of") to the father's given name Dias. So Diaz essentially means "son of Dias". The surname first appeared in written records in the 11th century as a distinguishing name for people in Spain.
One of the earliest recorded bearers of the name was Ruy Diaz de Vivar (c.1026-1099), a Castilian knight better known as El Cid, who played a pivotal role in the Reconquista, the centuries-long period of Christian conquest of Moorish territories across the Iberian Peninsula. The "Song of My Cid" (c.1200) is an important early literary work that references El Cid.
Pedro Diaz (c.1546-1618) was a famous Spanish Dominican friar and theologian who taught at the prestigious University of Salamanca. Juan Diaz de Solis (c.1470-1516) was a celebrated Spanish navigator and explorer who led the first European expedition to explore the territory that is now Argentina and Uruguay.
In Portugal, Bartholomeu Diaz (c.1450-1500) was a Portuguese explorer who was the first European to sail around the southern tip of Africa in 1488, then known as the Cape of Storms, but renamed the Cape of Good Hope by King John II. His voyage opened up an important trade route for Portugal.
Pedro Diaz Morante (1564-1636) was a Spanish poet and playwright who lived during the Golden Age of Spanish literature and whose poems were published in collections alongside works by Lope de Vega and Luis de Góngora.
Demographics
Ancestry and ethnicity for Diaz
Among Census respondents with the surname Diaz, the largest self-reported group is Hispanic at 91.9%. The next largest groups are White (5.4%) and Asian/Pacific Islander (1.3%).
The bar chart below shows how Diaz 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 Diaz surname at the time of the 2020 Census, not any inherent property of the name itself.
- Hispanic or Latino91.9% · 328,082
- White5.4% · 19,215
- Asian and Pacific Islander1.3% · 4,807
- Black or African American0.8% · 2,737
- Two or more races0.4% · 1,407
- American Indian and Alaska Native0.2% · 662
Timeline
Historical Census data for Diaz
Diaz 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
#55
National surname rank
Recorded bearers 347,636
+95,864 bearers (+38.1%)
Per 100,000 117.85
Rank movement Up 18 places
2020
#52
National surname rank
Recorded bearers 356,910
+9,274 bearers (+2.7%)
Per 100,000 119.41
Rank movement Up 3 places
| Year | Rank | Count | Per 100K | Count change | Rank change |
|---|---|---|---|---|---|
| 2000 | #73 | 251,772 | 93.33 | First available Census row | First available Census row |
| 2010 | #55 | 347,636 | 117.85 | +95,864 bearers (+38.1%) | Up 18 places |
| 2020 | #52 | 356,910 | 119.41 | +9,274 bearers (+2.7%) | Up 3 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 Diaz 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 | #55 | #52 | 5.5% |
| Count | 347,636 | 356,910 | 2.7% |
| Per 100K | 117.85 | 119.41 | 1.3% |
Between the 2010 and 2020 Census, the number of Diaz bearers went from 347,636 to 356,910 (+2.7% change). The surname moved up 3 positions in the national ranking, going from #55 to #52.
Notable bearers
Famous people with the surname Diaz
FAQ
Diaz surname: questions and answers
How many people in the U.S. have the surname Diaz?
Name Census estimates that about 409,278 living Americans carry the surname Diaz. Using the current population baseline, that works out to roughly 1 in 837 residents.
How common is Diaz?
Diaz ranks #52 in the 2020 Census surname tables and is classified on this site as "Common." The Census recorded the name at a frequency of 119.41 per 100,000 residents, which is about 119 people out of every 100,000.
How many people with this surname were counted in the Census?
The raw 2020 Census file counted 356,910 people with the surname Diaz. That is different from the site's living-bearer estimate (409,278), which projects the surname's present-day count by applying the Census frequency rate to the current U.S. population.
What does 119.41 per 100,000 actually mean?
It is the Census Bureau's normalized frequency measure. A rate of 119.41 per 100,000 means that if you picked a random group of 100,000 U.S. residents, you would expect about 119 of them to have the surname Diaz.
Has Diaz become more or less common over time?
Between 2010 and 2020, the surname Diaz went from 347,636 recorded bearers to 356,910. That is an increase of 9,274 (+2.7%). In the national ranking it rose from #55 to #52.
What does the Census say about the background of Diaz?
Among Census respondents with the surname Diaz, the largest self-reported group is Hispanic at 91.9%. The next largest groups are White (5.4%) and Asian/Pacific Islander (1.3%). 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 Diaz in the 2020 Census, accounting for 91.9% (328,082 people in the source table).
What is the full ancestry breakdown?
Diaz appears across multiple self-reported groups in the Census data. The largest shares in the 2020 file are Hispanic (91.9%), White (5.4%), Asian/Pacific Islander (1.3%). 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 Diaz (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 Diaz mean?
A Spanish patronymic surname derived from the given name Diego, meaning "supplanter" or "replacing." 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 Diaz (119.41 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 Diaz?
HowManyOfMe.org, our sister site, answers that with the living-bearer count in one glance.