2000
#5,917
National surname rank
Recorded bearers 5,358
First available Census row
Per 100,000 1.99
Rare Last name
Mortimer
From the Old French "mort mer," meaning "still water" or "dead sea," likely referring to someone living near a stagnant pool.
According to the 2020 US Census Bureau surname tables, roughly 6,124 Americans carry the last name Mortimer. That puts it at #6,150 in the national surname ranking, appearing at a frequency of 1.79 per 100,000 people (about 1 in 55,969 residents).
This page is the full Name Census profile for the Mortimer 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 Mortimer with 1881 census detail, origin facts and modern UK distribution where available.
Bearers in the US
6.1K
1 in 55,969
Census rank
#6,150
2020 decennial data
Per 100,000
1.8
Frequency rate
Recorded bearers
5.3K
rare in the US
Popularity narrative
The Census Bureau recorded 5,340 bearers of the surname Mortimer in its 2020 decennial surname file. At a rate of 1.79 per 100,000 residents, it holds the 6150th position in the national surname ranking.
Among Census respondents with the surname Mortimer, the largest self-reported group is White at 85.4%. The next largest groups are Black (7.4%) and Two or More Races (3.1%).
Origin
Meaning and origin of Mortimer
The surname Mortimer originated in England and France during the medieval period. It is derived from the Old French words "mort," meaning "dead," and "mer," meaning "sea" or "lake." The name likely referred to someone who lived near a stagnant, or "dead," body of water.
The earliest recorded instance of the Mortimer name appears in the Domesday Book of 1086, where it is spelled "Mortemere." This suggests that the name was already well-established in England by the time of the Norman Conquest in 1066.
One of the most famous early bearers of the Mortimer name was Roger Mortimer, 1st Earl of March (1287-1330), a powerful English nobleman who played a significant role in the conflict between King Edward II and his queen, Isabella of France. Mortimer eventually seized power and governed England as the de facto ruler until his execution in 1330.
Another notable Mortimer was Edmund Mortimer, 5th Earl of March (1391-1425), who was a claimant to the English throne during the latter stages of the Hundred Years' War. He was captured by the Welsh rebel Owain Glyndŵr and held captive for several years before being ransomed.
In the literary realm, John Mortimer (1923-2009) was a renowned English novelist, playwright, and screenwriter, best known for creating the character of the curmudgeonly barrister Horace Rumpole in the "Rumpole of the Bailey" stories.
The Mortimer name has also been associated with various place names in England, such as Mortimer's Cross in Herefordshire, where a decisive battle took place during the Wars of the Roses in 1461, and Mortimer's Hole, a natural underground cave system in Shropshire.
Other notable individuals with the Mortimer surname include Emily Mortimer (born 1971), an English actress known for films like "Shutter Island" and "Mary Poppins Returns," and Roger Mortimer (1909-1991), an English cricketer who played for Gloucestershire and captained the English national team.
Demographics
Ancestry and ethnicity for Mortimer
Among Census respondents with the surname Mortimer, the largest self-reported group is White at 85.4%. The next largest groups are Black (7.4%) and Two or More Races (3.1%).
The bar chart below shows how Mortimer 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 Mortimer surname at the time of the 2020 Census, not any inherent property of the name itself.
- White85.4% · 4,558
- Black or African American7.4% · 397
- Two or more races3.1% · 165
- Hispanic or Latino3.0% · 161
- Asian and Pacific Islander0.7% · 37
- American Indian and Alaska Native0.4% · 22
Timeline
Historical Census data for Mortimer
Mortimer 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
#6,195
National surname rank
Recorded bearers 5,521
+163 bearers (+3.0%)
Per 100,000 1.87
Rank movement Down 278 places
2020
#6,150
National surname rank
Recorded bearers 5,340
-181 bearers (-3.3%)
Per 100,000 1.79
Rank movement Up 45 places
| Year | Rank | Count | Per 100K | Count change | Rank change |
|---|---|---|---|---|---|
| 2000 | #5,917 | 5,358 | 1.99 | First available Census row | First available Census row |
| 2010 | #6,195 | 5,521 | 1.87 | +163 bearers (+3.0%) | Down 278 places |
| 2020 | #6,150 | 5,340 | 1.79 | -181 bearers (-3.3%) | Up 45 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 Mortimer 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 | #6,195 | #6,150 | 0.7% |
| Count | 5,521 | 5,340 | -3.3% |
| Per 100K | 1.87 | 1.79 | -4.5% |
Between the 2010 and 2020 Census, the number of Mortimer bearers went from 5,521 to 5,340 (-3.3% change). The surname moved up 45 positions in the national ranking, going from #6,195 to #6,150.
Notable bearers
Famous people with the surname Mortimer
FAQ
Mortimer surname: questions and answers
How many people in the U.S. have the surname Mortimer?
Name Census estimates that about 6,124 living Americans carry the surname Mortimer. Using the current population baseline, that works out to roughly 1 in 55,969 residents.
How common is Mortimer?
Mortimer ranks #6,150 in the 2020 Census surname tables and is classified on this site as "Rare." The Census recorded the name at a frequency of 1.79 per 100,000 residents, which is about 2 people out of every 100,000.
How many people with this surname were counted in the Census?
The raw 2020 Census file counted 5,340 people with the surname Mortimer. That is different from the site's living-bearer estimate (6,124), which projects the surname's present-day count by applying the Census frequency rate to the current U.S. population.
What does 1.79 per 100,000 actually mean?
It is the Census Bureau's normalized frequency measure. A rate of 1.79 per 100,000 means that if you picked a random group of 100,000 U.S. residents, you would expect about 2 of them to have the surname Mortimer.
Has Mortimer become more or less common over time?
Between 2010 and 2020, the surname Mortimer went from 5,521 recorded bearers to 5,340. That is a decrease of 181 (-3.3%). In the national ranking it rose from #6,195 to #6,150.
What does the Census say about the background of Mortimer?
Among Census respondents with the surname Mortimer, the largest self-reported group is White at 85.4%. The next largest groups are Black (7.4%) and Two or More Races (3.1%). 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 Mortimer in the 2020 Census, accounting for 85.4% (4,558 people in the source table).
What is the full ancestry breakdown?
Mortimer appears across multiple self-reported groups in the Census data. The largest shares in the 2020 file are White (85.4%), Black (7.4%), Two or More Races (3.1%). 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 Mortimer (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 Mortimer mean?
From the Old French "mort mer," meaning "still water" or "dead sea," likely referring to someone living near a stagnant pool. 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 Mortimer (1.79 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 Mortimer?
Find out how common the surname Mortimer is on our sister site HowManyOfMe.org — a quick modern estimate with the living-bearer count front and centre.