2000
#3,211
National surname rank
Recorded bearers 10,208
First available Census row
Per 100,000 3.78
Uncommon Last name
Mortensen
A Danish patronymic surname meaning "son of Morten," derived from the Latin name Martinus, referring to the Roman god Mars.
According to the 2020 US Census Bureau surname tables, roughly 12,701 Americans carry the last name Mortensen. That puts it at #3,181 in the national surname ranking, appearing at a frequency of 3.71 per 100,000 people (about 1 in 26,986 residents).
This page is the full Name Census profile for the Mortensen 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 Mortensen with 1881 census detail, origin facts and modern UK distribution where available.
Bearers in the US
13K
1 in 26,986
Census rank
#3,181
2020 decennial data
Per 100,000
3.7
Frequency rate
Recorded bearers
11K
uncommon in the US
Popularity narrative
The Census Bureau recorded 11,076 bearers of the surname Mortensen in its 2020 decennial surname file. At a rate of 3.71 per 100,000 residents, it holds the 3181st position in the national surname ranking.
Among Census respondents with the surname Mortensen, the largest self-reported group is White at 90.4%. The next largest groups are Hispanic (5.0%) and Two or More Races (2.9%).
Origin
Meaning and origin of Mortensen
The surname Mortensen is of Danish origin, with roots tracing back to the Middle Ages. It is a patronymic surname, which means it was originally derived from the given name of the bearer's father or ancestor.
The name Mortensen is believed to have originated from the Old Norse personal name "Mördr," which means "murder" or "killing." This name was likely given to a strong or fierce warrior or hunter. Over time, the name evolved into the Danish form "Morten," which is the equivalent of the English name "Martin."
One of the earliest recorded instances of the Mortensen surname can be found in the Danish Census of 1787, where several families with this name were listed as residents of various regions across Denmark.
In the 19th century, the Mortensen surname gained prominence with the birth of Viggo Mortensen (1858-1950), a Danish painter and illustrator known for his depictions of rural life in Denmark. His works are displayed in several museums across Scandinavia.
Another notable figure was Hans Mortensen (1817-1899), a Danish architect who designed several prominent buildings in Copenhagen, including the Ny Carlsberg Glyptotek museum and the Thorvaldsens Museum.
The Mortensen surname also has a strong presence in Norway, where it is often spelled as "Mortensen" or "Mortenson." One of the earliest recorded instances of this variant spelling can be traced back to the 16th century, when a man named Jørgen Mortenson was listed as a resident of Bergen, Norway.
In the United States, the Mortensen surname gained recognition with the birth of Mortensen M. Mortensen (1876-1958), a Danish-American businessman and philanthropist who co-founded the Mortensen Construction Company in Minneapolis, Minnesota.
Another noteworthy figure was Viggo Mortensen (born 1958), the American actor and producer of Danish descent, best known for his roles in films such as "The Lord of the Rings" trilogy and "Green Book."
Throughout history, the Mortensen surname has been associated with various professions, including artists, architects, businessmen, and more recently, actors and filmmakers. While its origins can be traced back to the Viking era, the name continues to be a prominent part of Scandinavian culture and heritage.
Demographics
Ancestry and ethnicity for Mortensen
Among Census respondents with the surname Mortensen, the largest self-reported group is White at 90.4%. The next largest groups are Hispanic (5.0%) and Two or More Races (2.9%).
The bar chart below shows how Mortensen 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 Mortensen surname at the time of the 2020 Census, not any inherent property of the name itself.
- White90.4% · 10,011
- Hispanic or Latino5.0% · 554
- Two or more races2.9% · 316
- Asian and Pacific Islander1.0% · 110
- Black or African American0.5% · 56
- American Indian and Alaska Native0.3% · 29
Timeline
Historical Census data for Mortensen
Mortensen 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
#3,282
National surname rank
Recorded bearers 11,013
+805 bearers (+7.9%)
Per 100,000 3.73
Rank movement Down 71 places
2020
#3,181
National surname rank
Recorded bearers 11,076
+63 bearers (+0.6%)
Per 100,000 3.71
Rank movement Up 101 places
| Year | Rank | Count | Per 100K | Count change | Rank change |
|---|---|---|---|---|---|
| 2000 | #3,211 | 10,208 | 3.78 | First available Census row | First available Census row |
| 2010 | #3,282 | 11,013 | 3.73 | +805 bearers (+7.9%) | Down 71 places |
| 2020 | #3,181 | 11,076 | 3.71 | +63 bearers (+0.6%) | Up 101 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 Mortensen 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 | #3,282 | #3,181 | 3.1% |
| Count | 11,013 | 11,076 | 0.6% |
| Per 100K | 3.73 | 3.71 | -0.7% |
Between the 2010 and 2020 Census, the number of Mortensen bearers went from 11,013 to 11,076 (+0.6% change). The surname moved up 101 positions in the national ranking, going from #3,282 to #3,181.
Notable bearers
Famous people with the surname Mortensen
FAQ
Mortensen surname: questions and answers
How many people in the U.S. have the surname Mortensen?
Name Census estimates that about 12,701 living Americans carry the surname Mortensen. Using the current population baseline, that works out to roughly 1 in 26,986 residents.
How common is Mortensen?
Mortensen ranks #3,181 in the 2020 Census surname tables and is classified on this site as "Uncommon." The Census recorded the name at a frequency of 3.71 per 100,000 residents, which is about 4 people out of every 100,000.
How many people with this surname were counted in the Census?
The raw 2020 Census file counted 11,076 people with the surname Mortensen. That is different from the site's living-bearer estimate (12,701), which projects the surname's present-day count by applying the Census frequency rate to the current U.S. population.
What does 3.71 per 100,000 actually mean?
It is the Census Bureau's normalized frequency measure. A rate of 3.71 per 100,000 means that if you picked a random group of 100,000 U.S. residents, you would expect about 4 of them to have the surname Mortensen.
Has Mortensen become more or less common over time?
Between 2010 and 2020, the surname Mortensen went from 11,013 recorded bearers to 11,076. That is an increase of 63 (+0.6%). In the national ranking it rose from #3,282 to #3,181.
What does the Census say about the background of Mortensen?
Among Census respondents with the surname Mortensen, the largest self-reported group is White at 90.4%. The next largest groups are Hispanic (5.0%) and Two or More Races (2.9%). 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?
White is the largest self-reported group for the surname Mortensen in the 2020 Census, accounting for 90.4% (10,011 people in the source table).
What is the full ancestry breakdown?
Mortensen appears across multiple self-reported groups in the Census data. The largest shares in the 2020 file are White (90.4%), Hispanic (5.0%), Two or More Races (2.9%). 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 Mortensen (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 Mortensen mean?
A Danish patronymic surname meaning "son of Morten," derived from the Latin name Martinus, referring to the Roman god Mars. 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 Mortensen (3.71 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 people have the last name Mortensen?
If you just want to know how many people are called Mortensen, HowManyOfMe.org gives you the headline number in one glance.