Having conceded an injury-time equaliser against Championship leaders Southampton last week, Ian Holloway's Seasiders were again frustrated in a game they dominated for long periods.
Matt Phillips and Lomana LuaLua were denied by the goal-frame in the first half, while Watford's England Under-21 goalkeeper Scott Loach was in impressive form.
Prince Buaben spurned the Hornets' two clearest openings, but the final whistle came as a relief to the Londoners who now lie five points clear of the relegation zone.
Ian Holloway's Blackpool will enter the festive period three points shy of the play-off places.
LuaLua replaced Chris Basham in the only change to the Blackpool side, while Lloyd Doyley came into the Watford defence after Carl Dickinson was struck down with a sickness bug.
Blackpool made a dominant start, with on-loan Wigan forward Callum McManaman and Phillips to the fore.
The latter almost opened the scoring in the seventh minute when he unleashed a fierce drive at the end of a mazy run, only to see the ball ricochet off the post and the back of prone goalkeeper Loach before being scrambled clear.
Moments later LuaLua cut in from the right and his shot went past the upright via a deflection off team-mate Gary Taylor-Fletcher.
McManaman skilfully evaded a challenge to shoot narrowly wide, and when LuaLua struck from 20 yards midway through the half the post came to Watford's rescue once more.
Having weathered a considerable storm, the Hornets had a chance to open the scoring in the 31st minute as Buaben nodded wide from Mark Yeates' cross.
On the stoke of half-time Troy Deeney found space in the right channel to spear the ball goalwards, but Blackpool 'keeper Matt Gilks got down and palmed to safety.
Normal service was resumed on the resumption and Taylor-Fletcher passed up a golden opportunity to give Blackpool a 50th-minute lead.
Loach did superbly to thwart the striker's initial close-range effort, but Taylor-Fletcher contrived to backheel wide with the goal at his mercy after McManaman retrieved the loose ball.
Blackpool's pressure subsided as the half went on and Buaben had Watford's best chance of the contest in the 65th minute when he blazed over from Michael Kightley's cross.
Phillips responded with another rampaging foray for the hosts and after Doyley denied him with a last-ditch tackle, Sean Dyche's side were forced to withstand a flurry of corners.
Veteran striker Kevin Phillips was introduced from the bench as Blackpool chased victory and headed over from close range following further good work from namesake Matt.
Loach saved his best work for the dying minutes as an excellent double save denied Seasiders' defensive duo Ian Evatt and Craig Cathcart from substitute Billy Clarke's free-kick.