Match ends, West Bromwich Albion 0, West Ham United 3.
Mark Noble scored twice as West Ham eased past West Brom to reclaim fifth place in the Premier League table.
The hosts had the best opportunities in the opening 15 minutes, but the Hammers soon took control.
Cheikhou Kouyate's header opened the scoring and the midfielder then set up Mark Noble, whose scuffed effort made it 2-0 before the break.
And Noble grabbed a second - his fourth goal in two games - when he volleyed home from Andy Carroll's ball in.
The Hammers, now unbeaten in 10 league matches, leapfrog Manchester United, who play leaders Leicester on Sunday.
And they have now reached their highest ever points haul in the Premier League with 59.
But the result leaves Tony Pulis' Baggies without a win in seven games.
West Ham have not lost a league game since their 1-0 defeat by Southampton in February and they look well set for a top-six finish - and a Europa League place.
Against a poor West Brom side, Dimitri Payet was impressive once again for the Hammers and he played a big part in two of the three goals.
The Frenchman had just switched to the right wing when he collected the ball and sent in an accurate cross for Kouyate to head in on 34 minutes.
Kouyate then turned provider when he raced forward unopposed and fed Noble, who managed to poke past Ben Foster on the stroke of half-time.
And it was Payet's weaving run which led to West Ham's third. The 29-year-old found Carroll out on the left, and the England striker's looping ball over the top was drilled in with force by Noble.
Leko: born in 1999
With West Brom's top-flight status all-but secure, Pulis handed a starting berth to 17-year-old Jonathan Leko - and he became the first player born in 1999 to start a Premier League match.
The young winger made an immediate impact, too, as he glided through the West Brom defence and supplied Craig Gardner, who saw two efforts kept out.
Leko then tricked his way forward again, but Gardner could only head wide of the target.
As the teenager's impact faded, and the Hammers took the lead, West Brom rarely looked a threat.
Striker Salomon Rondon had only four touches in the box all game, and their best effort in the second half was sent wide of the post by substitute Saido Berahino.
Man of the match - Dimitri Payet
What the managers said
West Brom manager Tony Pulis: "I thought we dominated the first 25 minutes but we had to take chances. You know they're going to get opportunities, and we've not had the breaks.
"We went 2-0 down when they had three shots. They had four shots, three goals. We had five or six opportunities and we've not scored.
"We've got a lot of talent in the academy and Jonathan [Leko] has got raw talent. He needs to be out playing against men. Under-21 football isn't enough. We have to get these kids out. He's got unbelievable talent."
West Ham manager Slaven Bilic: "We totally deserved it. They are physical and organised. They have a good home record against big teams and they were better in the first 25 minutes. We were on the back foot but then we started to stretch them.
"The goals helped - the first and second before the break. We scored magnificent goals from open play and it's a great win."
The stats you need to know
- Dimitri Payet is the fourth West Ham player to assist 10 goals in a Premier League season, following Matt Holmes (10, 1993-94), Eyal Berkovic (10 in 1997-98 and 11 in 1998-99) and Paolo di Canio (13 in 1999-2000).
- Only Southampton (14) have scored more headed goals than the Hammers (13) in the Premier League this season.
- Mark Noble has scored more Premier League goals this season (seven) than in his previous two seasons combined (five).
- Noble has scored four goals in his last two Premier League games, as many as he managed in his previous 57.
West Ham face Swansea at home on 7 May, while West Brom travel to Bournemouth on the same day.
- 5YacobSubstituted forGuimaraes Cordeiroat 62'minutes
- 8GardnerSubstituted forSessegnonat 78'minutes
- 14McCleanSubstituted forBerahinoat 61'minutes
- 30Guimaraes Cordeiro
- 28LanziniSubstituted forOxfordat 87'minutes
- 27PayetSubstituted forMosesat 81'minutes
- 15SakhoSubstituted forEmenikeat 66'minutes
- Lee Mason
- Shots on Target
Second Half ends, West Bromwich Albion 0, West Ham United 3.
Attempt missed. Saido Berahino (West Bromwich Albion) header from the centre of the box misses to the right. Assisted by Stéphane Sessegnon with a cross.
Attempt blocked. Reece Oxford (West Ham United) header from the right side of the six yard box is blocked. Assisted by Victor Moses with a cross.
Corner, West Ham United. Conceded by Salomón Rondón.
Corner, West Ham United. Conceded by Craig Dawson.
Winston Reid (West Ham United) wins a free kick in the defensive half.
Foul by Salomón Rondón (West Bromwich Albion).
Hand ball by Jonas Olsson (West Bromwich Albion).
Corner, West Bromwich Albion. Conceded by Angelo Ogbonna.
Hand ball by Andy Carroll (West Ham United).
Michail Antonio (West Ham United) wins a free kick in the defensive half.
Foul by Craig Dawson (West Bromwich Albion).
Attempt saved. Stéphane Sessegnon (West Bromwich Albion) right footed shot from outside the box is saved in the top right corner.
Substitution, West Ham United. Reece Oxford replaces Manuel Lanzini.
Foul by Winston Reid (West Ham United).
Saido Berahino (West Bromwich Albion) wins a free kick in the attacking half.
Attempt missed. Sandro (West Bromwich Albion) right footed shot from outside the box is too high. Assisted by Gareth McAuley following a corner.
Corner, West Bromwich Albion. Conceded by Mark Noble.
Attempt missed. Craig Dawson (West Bromwich Albion) left footed shot from the centre of the box misses to the left. Assisted by Stéphane Sessegnon with a cross following a corner.