After a 13th-place finish last term, the Hornets get their season underway on August 9 before a trip to face Norwich City at Carrow Road the following week.
Giuseppe Sannino’s side face the side relegated from the top flight and then travel to the New York Stadium to face newly-promoted Rotherham three days later.
The return fixtures against the Canaries and Steve Evans’ Rotherham again come in three days, with Norwich arriving at Vicarage Road on February 21.
Wolverhampton Wanderers will be the guests on Boxing Day before a trip to the Welsh capital to face Cardiff City on December 28.
A trip to the City Ground to face Nottingham Forest on April 15 starts the season run-in for Watford, who will face Sheffield Wednesday on the final day.
Sannino’s side then host Birmingham ahead of a trip to the Amex Stadium to face Brighton before the season climax against the Owls on May 2.
Opening three fixtures:
Bolton Wanderers (h)
Norwich City (a)
Rotherham United (a)