Hornets boss Malky Mackay told the club's website: "Jonathan found himself on the bench last season.
"He trained with the first-team and it may have been surprising for him, but he's worked hard and it's paid off."
Bond will hope to follow in the footsteps of Scott Loach who, under the tutorship of goalkeeper coach Alec Chamberlain, made the step up from the Watford youth team to become a first-team regular.
"I'm delighted he is under the care of Alec, who has already brought Ben Foster on leaps and bounds, as well as our own Scott Loach," Mackay added.
Source: BBC Sport
Source: BBC Sport