Seamus
Seamus is an Irish masculine name derived from Old Irish Sémús, meaning "supplanter".
Name Census estimates that about 7,507 living Americans carry the first name Seamus. The name is used almost exclusively for boys. The average person named Seamus today is around 21 years old, and the year with the single highest number of Seamus births was 2008 (298 babies).
This page is the full Name Census profile for Seamus. 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.
For a British comparison, Name Census UK has a UK baby-name profile for Seamus with official rankings and popularity over time.
People living today
7.5K
~ 1 in 45,658 Americans
Peak year
2008
298 babies that year
Average age
21
years old
2024 SSA rank
#1,450
Tracked since 1957
Census
Seamus in the 2020 Census
The 2020 Census recorded 6,960 people with the first name Seamus, which placed it at #3,142 in the published first-name tables. This is a snapshot of people who already had the name at the time of the Census.
The SSA sections elsewhere on this page answer a different question: how often parents gave the name to babies over time. The "people living today" figure on this page is different again: it is a current estimate built from SSA birth records and age-based survival rates, so the two numbers are not expected to match exactly.
2020 Census rank
#3,142
National first-name rank
People counted
7.0K
6,960 in the published race/origin table
Per 100,000
2.3
People with this name in 2020
Largest reported group
White
90.2% of people with this name
Demographics
Ancestry and ethnicity for Seamus
In the 2020 Census race and Hispanic-origin table, the largest reported group for people named Seamus is White at 90.2%. The next largest groups are Hispanic (4.4%) and Two or More Races (4.3%). These figures describe the people who had the name in 2020, not any inherent property of the name itself.
The bar chart below shows how people with the first name Seamus 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 name, the Bureau suppresses the figure to protect individual privacy, which is why some names show fewer than six slices.
Percentages are shown so the breakdown is easy to read across every published category. Because the 2020 Census first-name file also includes raw headcounts for each group, Name Census can show those alongside the percentages in the legend and hover tooltip.
Keep in mind that these are self-reported numbers. A first name does not determine a person's race or ethnicity, and the distribution you see here reflects the specific population who happened to carry the name Seamus at the time of the 2020 Census, not any inherent property of the name itself.
- White90.2% · 6,280
- Hispanic or Latino4.4% · 305
- Two or more races4.3% · 296
- Asian and Pacific Islander0.6% · 43
- Black or African American0.3% · 22
- American Indian and Alaska Native0.2% · 14
Popularity
Seamus: popularity over time
The SSA tracks Seamus from the 1950s through to the 2020s, spanning 8 decades of birth certificate data. The biggest single decade for the name was the 2000s, with 2,446 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
Seamus 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 Seamus during that decade, along with a combined total. This is useful for spotting eras where the name surged or retreated.
Geography
Where Seamus' live
The SSA's state-level files cover 30 states and territories. New York, Massachusetts, California recorded the most babies named Seamus, while Montana, Georgia, District of Columbia recorded the fewest. The average across all reporting states is about 175 registrations each.
Origin
Meaning and history of Seamus
The name Seamus is a traditional Irish masculine given name derived from the Gaelic name Séamas, which is the Irish version of the name James. The name Séamas itself originated from the Late Latin name Iacomus, which in turn came from the Hebrew name Ya'aqov, meaning "supplanter" or "one who follows".
The name Seamus has been prevalent in Ireland for centuries and was particularly popular among Irish Catholics. Its earliest recorded use dates back to the 12th century, when it appeared in various medieval Irish manuscripts and annals.
One of the earliest known historical figures with the name Seamus was Seamus Ó Cilín, an Irish poet and historian who lived in the late 16th and early 17th centuries. He is best known for his work "Eochair-Sgiath an Aifrinn" (The Mass Key), a treatise on the celebration of the Mass.
Another notable bearer of the name was Seamus Heaney, the renowned Irish poet, playwright, and academic who lived from 1939 to 2013. Heaney was awarded the Nobel Prize in Literature in 1995 for his "works of lyric beauty and ethical depth, which exalt everyday miracles and the living past".
In the realm of Irish politics, Seamus Mallon, who lived from 1936 to 2020, was a prominent figure. He served as the Deputy Leader of the Social Democratic and Labour Party (SDLP) and played a crucial role in the Northern Ireland peace process, including the Good Friday Agreement.
Seamus Deane, born in 1940, is an Irish writer, critic, and academic. He is best known for his novels "Reading in the Dark" and "The Aunt's Story", which explore themes of Irish identity and the legacy of the Troubles.
Another important figure was Seamus Costello, an Irish republican paramilitary and founding member of the Irish Republican Army (IRA). He lived from 1939 to 1977 and played a significant role in the early stages of the Troubles in Northern Ireland.
These are just a few examples of notable individuals throughout history who have borne the name Seamus, a name deeply rooted in Irish culture and tradition.
People
Seamus + last name combinations
How many people share a full name with Seamus as the first name? Click a combination below to see the estimate, or search any pairing.
Related
Other names starting with S
Other first names starting with S with a similar number of bearers.
FAQ
Seamus: questions and answers
How many people in the U.S. are named Seamus?
Name Census puts the figure at roughly 7,507 living Americans. We arrive at this by taking every SSA birth registration for Seamus 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 45,658 US residents.
Is Seamus a common name?
We classify Seamus as "Rare". It ranks above 97.3% of all first names in the SSA dataset by living bearers. Across the full history of the data, 7,656 babies have been registered with this name.
When was Seamus most popular?
The single biggest year for Seamus was 2008, when 298 babies received the name. The fact that the average living Seamus is about 21 years old gives you a rough sense of which era contributed the most bearers who are still alive today.
How common was Seamus in the 2020 Census?
The published 2020 Census first-name tables recorded 6,960 people with the name Seamus, or 2.30 per 100,000 residents. That placed it at #3,142 in the national Census ranking for first names.
Why is the Census count different from the living estimate?
Because they measure different things. The Census figure is a count of people who had the name Seamus in 2020. The living estimate aims to answer a current question instead: how many people with the name are alive today, based on SSA birth records and age-based survival rates. Since one number is a 2020 snapshot and the other is a present-day estimate, they are not expected to be identical.
What does the Census say about the gender split for Seamus?
In the 2020 Census sex table, Seamus appears almost entirely male. Of the 6,955 people counted with this name, 99.7% were male and only a very small share were female. The Census view is a snapshot of people living with the name in 2020, while the SSA section above tracks births across time.
What does the Census say about the background of people named Seamus?
In the 2020 Census race and Hispanic-origin table, the largest reported group for people named Seamus is White at 90.2%. The next largest groups are Hispanic (4.4%) and Two or More Races (4.3%). These figures describe the people who had the name in 2020, not any inherent property of the name itself. The percentages in the chart above come from self-reported race and Hispanic-origin responses in the 2020 Census.
Which group reports the name Seamus most often in the Census?
White is the largest reported group for people named Seamus in the 2020 Census, accounting for 90.2% (6,280 people in the published table).
Why can the Census sex total and race total differ slightly?
The Census Bureau published separate 2020 tables for sex and for race/Hispanic origin, and the released figures can differ slightly because of privacy protection in the public files. That is why this page treats the gender section and the race/origin section as two related snapshots instead of forcing them into one identical total.
Does every first name have Census demographic data?
No. The public Census first-name release only includes names that met the Bureau's publication rules, so many rarer names in the SSA files have no Census demographic snapshot. When that happens, the SSA trend, gender history, and state sections still appear, but the 2020 Census demographic sections are omitted.
What does the SSA popularity chart show?
The chart tracks births, not the number of people alive with the name today. Each point shows how many babies were given the name Seamus in that year. That makes it useful for spotting when the name rose, peaked, or faded.
Is Seamus a male name?
Yes, 100.0% of people registered as Seamus 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.
Is Seamus still being used today?
Yes. The SSA still recorded Seamus in 2024, and the page above shows its latest-year rank where available. A name can be well past its peak and still remain in steady use, especially if it built up a large population over earlier decades.
Why can a name have a lot of living bearers even if it is not trendy now?
Because living-bearer counts and current baby-name popularity measure different things. A name like Seamus can build up a very large population over many decades, even if fewer parents are choosing it now than they did at its peak.
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.
How common is the name Seamus?
For a faster, more casual read, check HowManyOfMe.org — our sister site built around that single question.