Lou Costello
There are approximately 2 people named Lou Costello living in the United States today. That makes this name combination very rare, occurring at a rate of about 1 in 171,377,169 Americans.
This estimate combines SSA birth records for the first name Lou with Census Bureau frequency data for the surname Costello. Below you will find a breakdown of both names, including popularity trends, gender data, and Census demographics where available.
Expected bearers
2
1 in 171,377,169
Named Lou
16K
Alive today
Named Costello
35K
Alive today
US population
343M
Denominator
Estimated living: 16K
Rarity: Uncommon
Gender: Unisex
Peak year: 1954
Average age: 65
Top Census group: White (75.0%)
Estimated bearers: 35K
Rarity: Uncommon
Census rank: #1,121
Per 100K: 10.28
Top ancestry: White (87.5%)
First name trend
Lou: popularity over time
Year-by-year SSA birth registrations for the first name Lou. The peak year was 1954 with 1,547 births. The average person named Lou today is 65 years old.
Babies born per year
Demographics
Ancestry and ethnicity for Lou
Self-reported race and ethnicity breakdown for people with the first name Lou, from the 2020 US Census Bureau first-name tables. The largest published group is White at 75.0%.
The bar chart below shows how people with the first name Lou described their own race and ethnicity on the 2020 Census form. These are self-reported numbers, and they describe the population who happened to carry the name Lou at the time of the Census. A first name does not determine a person's race or ethnicity.
- White75.0% · 12,693
- Black or African American10.1% · 1,711
- Asian and Pacific Islander6.1% · 1,024
- Hispanic or Latino5.6% · 950
- Two or more races2.3% · 382
- American Indian and Alaska Native0.9% · 156
Ethnicity
Ancestry of the Costello surname
Self-reported race and ethnicity breakdown for people with the surname Costello, from the 2020 US Census Bureau. The largest group is White at 87.5%.
The bar chart below shows how people with the surname Costello described their own race and ethnicity on the 2020 Census form. These are self-reported numbers, and they describe the population who happened to carry the surname Costello at the time of the Census. A surname does not determine a person's race or ethnicity.
- White87.5% · 26,900
- Hispanic or Latino7.1% · 2,177
- Two or more races2.8% · 862
- Black or African American1.5% · 453
- Asian and Pacific Islander0.8% · 254
- American Indian and Alaska Native0.3% · 82
Methodology
How we calculated this
The first name Lou has a living-bearer frequency of 0.0046% of the US population, based on 15,873 estimated living Americans carrying this first name (from SSA birth records going back to 1880, adjusted for mortality using CDC life tables).
Even though the Census Bureau now publishes first-name tables, we do not use that file as the main first-name input for this estimate. The latest first-name Census snapshot is from 2020, which makes it 6 years old today. Because Census first-name data is only released once every 10 years, SSA birth records plus CDC survival rates give a better current estimate of how many people are likely alive with the name Lou right now.
The surname Costello appears at a rate of 10.28 per 100,000 residents in the 2020 Census Bureau surname file, which translates to a frequency of 0.0103%.
Multiplying these two independent frequencies against the current US population of 342,754,338 gives an expected count of approximately 2 people with the full name Lou Costello. This assumes statistical independence between first and last names, which is a simplification but produces reasonable estimates for most combinations.
Related
Other people named Lou
Related
Other people with the surname Costello
FAQ
Lou Costello: questions and answers
How many people are named Lou Costello?
We estimate approximately 2 people in the United States share the full name Lou Costello. That works out to about 1 in 171,377,169 Americans. This is calculated by combining the first-name frequency (0.0046%) with the surname frequency (10.28 per 100K) against the current US population.
How rare is the name Lou Costello?
We classify Lou Costello as "Very Rare". About 1 in 171,377,169 Americans share this exact first and last name combination.
Is Lou a male or female name?
Lou is predominantly unisex. Out of 38,049 total SSA registrations, 10.5% were male and 89.5% were female. See the full Lou profile for detailed gender data.
Where does this data come from?
First-name data comes from the Social Security Administration's national baby name files (1880 to 2024). Surname data comes from the 2020 US Census Bureau decennial surname tables. Living-bearer estimates use CDC actuarial life tables to adjust for mortality. Read the full methodology.
How many people share the full name Lou Costello?
HowManyOfMe.org, our sister site, answers that with the living-bearer count in one glance.