Cognomen Ross-Thomas (Ross-Thomas 
) , in the entire world, is a very rare surname. The family name Ross-Thomas is characteristic of the United Kingdom, where it is a very rare surname, and the United States, where it is an extremely rare surname. Parts of the name also exists independently as a last name Ross, and a first name Thomas.
| VARIANT | COUNTRY |
|---|---|
| Ross-Thomas | United States, United Kingdom |