| Surname | Mother Tongue | State of Origin |
|---|
| Kachwaha | | |
| Kak | Dogri; Kashmiri | Jammu & Kashmir |
| Koshy | | |
| Kushwaha | Hindi | Uttar Pradesh |
| Kushwaha | Marwari; Garhwali | North Indian (Himachal, Rajasthan, Uttarakhand, U.P, Delhi) |
| Kushwaha | Hindi | Madhya Pradesh |
| Kazi | (Muslim's) | |
| Keshaw | | |
| Keyush | | |
| Khawaja | (Muslim's) | |