Globally, Onufreichuk (Onufreichuk 
, Онуфрейчук 
) is an extremely rare unknown gender first name. Predominantly, Onufreichuk is the last name as well as the forename.
| VARIANT | COUNTRY |
|---|---|
| Onufreichuk | Canada, Ukraine |
| Онуфрейчук | Belarus, Russia, Kazakhstan, Ukraine |