If you just said to yourself "It's gotta be Grimsdottir, Wamboldt, and Zeleznik," you might want to take another shot at this.

By the way, those three surnames above came off a list of the least common surnames in America. (thanks to Mongabay.com).

For the most common we turn to a name that, thanks to some serious advertising over the last decade or so, has become pretty much a household name: Ancestry.com.

They recently published their list of the most common surnames in America, and yes, you've heard all these names plenty of times. Odds are you might even carry one of these last names.

First off, the most common surname in Illinois is also the most common surname in the entire country:

Smith.

Smith, along with Johnson, Miller, Jones, Williams, and Anderson make up most of the most common surnames all across the country.

The top three in Illinois are: Smith, Johnson, and Williams.

  • In Wisconsin, it's Johnson, Smith, and Anderson.
  • In Iowa, it's Smith, Williams, and Johnson.
  • In Indiana, it's Smith, Miller, and Johnson.
  • In Missouri, it's Smith, Johnson, and Williams.

Some other notes about common surnames from Ancestry:

If you are in the Northwest, you are more likely to come across an Anderson than a Brown, which is slightly more common on the East Coast.

Only the Southwestern portion of the country really has a lot of variety. States like Texas, California, New Mexico, and Arizona — where there are large Latino populations — boast a variety of names like Garcia, Hernandez, Martinez, and Chavez.

And then there’s Hawaii, whose three most-common surnames — Lee, Wong and Kim — don’t even appear in the top three anywhere else in the country.

And Massachusetts, with its large Irish population, is the only state that has Sullivan in its top three.