Guilherme
A masculine Portuguese name of Germanic origin meaning "wilful protector".
Name Census estimates that about 502 living Americans carry the first name Guilherme. The name is used almost exclusively for boys. The average person named Guilherme today is around 19 years old, and the year with the single highest number of Guilherme births was 2006 (39 babies).
This page is the full Name Census profile for Guilherme. Below you will find a gender breakdown showing how the name splits between male and female registrations, a year-by-year popularity chart stretching back to 1880, decade-level totals, the top US states for this name, its meaning and etymology, and a set of frequently asked questions with data-backed answers.
People living today
502
~ 1 in 682,778 Americans
Peak year
2006
39 babies that year
Average age
19
years old
2024 SSA rank
#12,902
Tracked since 1921
Popularity
Guilherme: popularity over time
The SSA tracks Guilherme from the 1920s through to the 2020s, spanning 6 decades of birth certificate data. The biggest single decade for the name was the 2000s, with 257 total registrations. Usage has dropped considerably from its 2000s peak. The most recent decade brought in only a fraction of the registrations that the name once attracted.
Babies born per year
Decades
Guilherme by decade
The table below breaks the full SSA timeline into ten-year windows. Each row shows how many male and female babies were given the name Guilherme during that decade, along with a combined total. This is useful for spotting eras where the name surged or retreated.
Geography
Where Guilhermes live
The SSA's state-level files cover 4 states and territories. Massachusetts, New Jersey, Connecticut recorded the most babies named Guilherme, while Florida, Connecticut, New Jersey recorded the fewest. The average across all reporting states is about 50 registrations each.
Origin
Meaning and history of Guilherme
Guilherme is a masculine given name of Portuguese origin, derived from the Germanic name Willahelm, which is a combination of two elements: "wil" meaning "will" or "desire," and "helm" meaning "protection" or "helmet." The name can be traced back to the Middle Ages, around the 12th century.
The name Guilherme became popular in Portugal during the Medieval period, particularly after the birth of King Afonso Henriques, the first King of Portugal. His mother, Countess Teresa of Portugal, had a close advisor named Guilherme de Montrior, who played a significant role in the formation of the Kingdom of Portugal. This association likely contributed to the name's widespread use among the Portuguese nobility.
One of the earliest recorded instances of the name Guilherme can be found in the "Cantigas de Santa Maria," a collection of 420 poems and songs written in Galician-Portuguese during the reign of King Alfonso X of Castile and Leon (1221-1284). The name appears in several of these cantigas, indicating its use in the 13th century.
Throughout history, several notable figures have borne the name Guilherme. One of the most famous was William the Conqueror (c. 1028-1087), the first Norman King of England, whose French name was Guillaume. Another prominent figure was William of Ockham (c. 1287-1347), an English Franciscan friar and philosopher known for his principle of parsimony, often referred to as "Occam's Razor."
In Portugal, Guilherme de Valença (c. 1225-1279) was a prominent Catholic priest and the first Archbishop of Valencia, Spain. Guilherme Gonzaga (c. 1532-1587) was an Italian nobleman and military leader who served as the first Duke of Mantua and Montferrat. Also noteworthy is Guilherme de Nassau (1533-1584), known as William the Silent, who was a prominent leader in the Dutch Revolt against Spanish rule and is considered the founder of the Netherlands.
Other historical figures with the name Guilherme include Guilherme de Machaut (c. 1300-1377), a renowned medieval French poet and composer, and Guilherme IV (1765-1837), the King of the United Kingdom of Great Britain and Ireland and King of Hanover from 1830 until his death.
People
Guilherme + last name combinations
How many people share a full name with Guilherme as the first name? Click a combination below to see the estimate, or search any pairing.
Related
Other names starting with G
Other first names starting with G with a similar number of bearers.
FAQ
Guilherme: questions and answers
How many people in the U.S. are named Guilherme?
Name Census puts the figure at roughly 502 living Americans. We arrive at this by taking every SSA birth registration for Guilherme going back to 1880 and adjusting each cohort for expected survival using CDC actuarial life tables. The result is an age-weighted living-bearer count, not a raw birth total. That works out to about 1 in 682,778 US residents.
Is Guilherme a common name?
We classify Guilherme as "Very Rare". It ranks above 84.6% of all first names in the SSA dataset by living bearers. Across the full history of the data, 514 babies have been registered with this name.
When was Guilherme most popular?
The single biggest year for Guilherme was 2006, when 39 babies received the name. The fact that the average living Guilherme is about 19 years old gives you a rough sense of which era contributed the most bearers who are still alive today.
Is Guilherme a male name?
Yes, 100.0% of people registered as Guilherme in the SSA data are male. You can see the full per-sex comparison in the gender distribution section above, which includes the latest year rank, birth count, and peak year for each sex.
Where does this data come from?
First-name figures come from the Social Security Administration's national baby name files, which cover every name on a birth certificate from 1880 to 2024. Living-bearer estimates layer in CDC actuarial life tables broken out by sex to account for mortality. The population baseline (342,754,338) is the Census Bureau's latest national estimate. You can read the full calculation on our methodology page.