Preston North End and Leeds United remain within touching distance of the Baggies after wins over Huddersfield Town and Blackburn Rovers respectively.
At the other end of the table, new boss Michael O'Neill inspired Stoke City to a 4-2 win over Barnsley in his first game since taking charge of the club, a result that lifts the Potters above the Tykes at the foot of the table.
Elsewhere, Nottingham Forest edged out Derby County in the East Midlands derby, while there were also wins for Fulham, Millwall, Reading and Brentford.
BAGGIES STAY TOP AFTER LIVERMORE STUNNER
Jake Livermore's second goal of the season was enough for West Brom to edge out Hull at KCOM Stadium.
The 29-year-old midfielder finished off a short corner routine in spectacular style after 28 minutes, taking a touch to control the ball 20 yards from goal and unleashing a rocket of a right-footed shot into the bottom corner of the Tigers' net.
Hull started the second half brightly and Kevin Stewart missed crucial chances as Slaven Bilic's side found itself exposed at the back.
But the visitors should have doubled their lead when Matheus Pereira — their outstanding creative player so far this season — sent a chip narrowly over the crossbar, but Bilic's table-toppers claimed all three points nonetheless.
BAMFORD ON TARGET AS WHITES WIN AGAIN
Leeds went into its clash against Blackburn unbeaten in four matches but striker Patrick Bamford was without a goal at Elland Road since April.
The former Middlesbrough striker ended his home drought after a foul on Luke Ayling earned a dominant Leeds side a penalty, Bamford coolly sending Christian Walton the wrong way as he stroked the ball home.
Bamford had a hand in the Whites' second, touching Kalvin Phillips's floated ball deftly into the path of Jack Harrison, who sent an angled shot in off the far post.
But slack marking allowed Derrick Williams to head Blackburn back into the game five minutes before half-time, the full-back rising to meet Stewart Downing's cross for his third goal of the season from 12 yards.
A combative Rovers side failed to break Marcelo Bielsa's men down, however, as they collected back-to-back Championship wins for the first time since August.
PRESTON TOO STRONG FOR RESURGENT TERRIERS
Huddersfield's recent revival came to a crashing halt at Deepdale as Preston registered a third consecutive league win with a 3-1 victory.
The Terriers were unbeaten in seven league games but never looked like clawing their way back into the game after Jayden Stockley had given the hosts a fourth-minute lead.
Alan Browne doubled that advantage shortly after the half-hour mark, while Paul Gallagher added a third with a penalty five minutes after the interval.
Juninho Bacuna pulled one back for the visitors 16 minutes from time, but it did little to take the gloss off another impressive win for Alex Neil's side.
O'NEILL MAKES INSTANT IMPACT AT STOKE
O'Neill made a superb start to life with struggling Stoke, guiding them to an emphatic win over Barnsley at Oakwell.
A Sam Clucas brace and goals from Joe Allen and Lee Gregory helped the Potters end a run of three consecutive defeats and start life after Nathan Jones in style.
Elsewhere, Lewis Grabban scored the only goal of the game as Forest edged out local rival Derby, while Fulham registered a 1-0 win at Birmingham City.
Millwall overcame Charlton Athletic 2-1, Reading powered past Luton Town 3-0 and Brentford beat Wigan Athletic by the same scoreline.
In the day's other games, Middlesbrough drew 2-2 away at Queens Park Rangers and Swansea City scored deep into stoppage-time to draw 2-2 with Sheffield Wednesday.