Cognomen Thadeo (Thadeo 
) , in the entire world, is quite a common surname. The last name Thadeo is habitual in Tanzania, where it is quite a common surname, Brazil, where it is a very rare surname, and Mexico. Likewise, Thadeo is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Thadeo | Tanzania, Brazil, Mexico, United States, Philippines |