Last season Williams refereed the Italy-France match and this season he has his 11th major international when he will be in Dublin for the Ireland-Scotland encounter on March 27.
Whitehouse, who has controlled six major internationals - the last being Scotland vs Ireland last September - will be in the middle for the Italy-Scotland match in Rome on March 6.
The games involving Wales will be controlled by the following: - February 14 - vs Scotland (Millennium Stadium) - Donal Courtney (Ireland). February 22 - vs Ireland (Dublin) - Joel Jutge (France). March 7 - vs France (Millennium Stadium) - Stuart Dickinson (Australia). March 20 - vs England (Twickenham) - Andrew Cole (Australia). March 27 - vs Italy (Millennium Stadium) - Mark Lawrence (South Africa).
Courtney, a 39-years-old financial director from Dublin, is a newcomer to the panel, but he did control the Scotland-Italy non-championship match last September and the Parker Pen Shield final between Caerphilly and Castres last season.
The other referees to be used in the Six-Nations will be - Chris White (England), Andy Turner (South Africa), Alan Lewis and Alain Rolland (both Ireland), Pable Deluca (Argentina), Paul Honiss and Kelvin Deaker (both New Zealand) and Scott Young (Australia).