How many surnames start with O?

18 of the 581 surnames in Icillion start with O, for example O'Brien, Ortiz and Oliveira.

What is the longest name among surnames that start with O?

The longest is “O'Sullivan” and the shortest is “Owen”.

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18 surnames start with O, from “O'Brien” to “Owen”. Every one of them counts as an answer in Icillion.

O is the 15th most common first letter in this list: 18 of the 581 surnames (3%).
Shortest: “Owen”. Longest: “O'Sullivan”.
1 can be spelled more than one way, and all the spellings count.

How many surnames start with O?: 18 of the 581 surnames in Icillion start with O, for example O'Brien, Ortiz and Oliveira.
What is the longest name among surnames that start with O?: The longest is “O'Sullivan” and the shortest is “Owen”.

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