Family name Simpson-Kothari (Simpson-Kothari 
) , in all the world, is an extremely rare last name. The cognomen Simpson-Kothari is habitual in Northern Europe, particularly the United Kingdom, where it is an extremely rare surname. Parts of the name also exists independently as a last name Simpson, and a last name Kothari.
| VARIANT | COUNTRY |
|---|---|
| Simpson-Kothari | United Kingdom |