How Rare Is Your Last Name? A Look at American Surnames

First names get all the attention, but your last name has a rarity story too. It just runs on different data. Here is how common American surnames really are, how the rarity is measured, and how to find out where your own family name lands.

The data behind surnames

Surname rarity comes from the U.S. Census Bureau 2010 surname file, a public snapshot that counts 265,667,228 people across 162,253 last names. Unlike the first-name data, which is 145 years of births, this is a single picture of the living population, which makes it a cleaner read on how common a family name is today.

Every count turns into a simple "1 in X" figure. If a name is held by 1 in 109 people, roughly one person in any random group of 109 carries it. The bigger that number, the rarer the name.

The most common American surnames

Rank	Surname	People	Rarity
1	Smith	2,442,977	1 in 109
2	Johnson	1,932,812	1 in 137
3	Williams	1,625,252	1 in 163
4	Brown	1,437,026	1 in 185
5	Jones	1,425,470	1 in 186
6	Garcia	1,166,120	1 in 228
7	Miller	1,161,437	1 in 229
8	Davis	1,116,357	1 in 238
9	Rodriguez	1,094,924	1 in 243
10	Martinez	1,060,159	1 in 251

Smith leads, shared by nearly 2.5 million Americans, about 1 in every 109 people. Garcia at number 6 is a good marker of how the country's names have shifted, now more common than long-standing names like Miller and Davis. By the time you reach the tenth most common name, Martinez, you are already down to roughly 1 person in 250, which shows how quickly a family name stops being everywhere once you leave the very top of the list.

How common is your last name, really

Most last names are nowhere near the top ten. The list runs 162,253 names deep, and the drop-off is steep. A name in the low thousands by rank might be carried by a few hundred thousand people. A name ranked in the tens of thousands might be shared by only a few thousand. And below that, the file stops naming individual surnames at all.

That floor is the key thing to understand about how common your last name is. The census file only lists names held by at least 100 people. Every rarer family name gets grouped into a single "all other names" bucket. So if you search your surname and it is not listed, that is itself the answer: fewer than 100 Americans carry it, which puts you well into rare territory, rarer than the vast majority of named surnames in the country.

How many people share your last name

The "1 in X" figure answers this directly. Take the population, divide by that ratio, and you have a rough count of how many people carry the name. Smith, at 1 in 109, works out to nearly 2.5 million people. A name at 1 in 100,000 works out to a few thousand nationwide. A name that is not in the file at all is shared by fewer than 100 people across the whole country.

This is why two people with different last names can both feel their name is "normal." One might share it with two million others; the other with two thousand. Both feel common in their own circle, because you rarely meet the millions who share the popular name or notice how few share the rare one.

The rarest last names

There is no single "rarest last name in the world," because rarity depends on the country and the record you measure against. In the U.S. census file, the rarest named surnames are the ones sitting right at the 100-person cutoff, and below them sit tens of thousands of family names too rare to list individually at all.

Truly rare American surnames tend to fall into a few groups: names carried by a single immigrant family that never spread widely, names altered or invented at a port of entry generations ago, and regional names that stayed tied to one small community. If your last name draws blank stares and constant spelling corrections, there is a good chance it lives in that unnamed tail of the data, shared by only a handful of families nationwide.

First names vs last names

The rarity idea is identical for both: how many people share it, turned into a "1 in X" figure and a tier. Two differences are worth knowing.

• The source. First names come from birth records back to 1880. Surnames come from the 2010 census of living people.
• The floor. The surname file only lists names held by at least 100 people. Rarer family names are grouped together, so if yours is not listed, it is carried by fewer than 100 Americans.

Check yours

Your full name is really two rarity scores. See where your family name lands with the Surname Rarity Checker, then run your first name too. Together they tell you just how unlikely the whole combination is. If you want the wider picture on unusual family names, the piece on the rarest names in America digs into what makes a name land in that rare tail.

Common questions

How rare is my last name? It depends on how many people share it. Look up your surname in the Surname Rarity Checker, which uses the 2010 U.S. Census file, and it returns a "1 in X" figure and a rarity tier. If your name is not listed, fewer than 100 Americans carry it, which makes it rare.

How common is my last name? The same check answers this from the other side. A common name like Smith or Johnson shows up as 1 in a few hundred people. A name that is not in the census list is uncommon by definition, since it is held by fewer than 100 people nationwide.

How many people have my last name? Take the "1 in X" figure from the checker and divide the U.S. population by X. Smith at 1 in 109 comes to about 2.5 million people. A name that is not listed is shared by fewer than 100 people across the country.

What is the rarest last name? There is no single answer, because it depends on the country and record. In the U.S. census file, the rarest named surnames sit at the 100-person floor, and tens of thousands of even rarer family names are grouped together below that, too uncommon to list on their own.

Is surname rarity measured the same way as first-name rarity? The idea is the same, a "1 in X" share, but the data differs. Surnames come from the 2010 census of living people, while first names come from birth records going back to 1880.