On-loan striker Daniel Sturridge sent Bolton heading down Wembley way with a spring in their step after this emphatic victory at the Reebok Stadium.
Sturridge, though, will be there in spirit only when they face Stoke in an FA Cup semi-final a week tomorrow as he played for Chelsea earlier in the competition.
He took his tally to six goals in eight games today and has arguably been one of the best signings of the January transfer window.
Lee Chung-yong was also on target and while Bolton have much to look forward to the future looks bleak for West Ham.
They remain deep in relegation trouble and manager Avram Grant cut a disconsolate figure in the stand as he served a touchline ban.
Bolton almost got off to a perfect start after Kevin Davies picked out Sturridge in the penalty area in the third minute.
He fired in a shot that took a deflection off West Ham defender Manuel da Costa. Gary Cahill then got on the end of Martin Petrov's corner but saw his header go wide of the post.
Bolton kept up the pressure and full back Gretar Steinsson raced to the byline. He picked out Kevin Davies and the skipper tried to release Sturridge with a clever little chip but put too much weight on the ball.
The home side took the lead in the 14th minute with a superb strike by Sturridge after he was played in by Johan Elmander.
Sturridge carved an opening for himself out of nothing before curling a shot beyond Robert Green and into the corner.
Kevin Davies should have added a second in the 18th minute but dragged his effort wide but a minute later Bolton forged 2-0 ahead.
West Ham failed to close down Martin Petrov and he swung in a cross that was headed firmly home by Lee.
Petrov was revelling in the space afford to him and cracked in a shot after 28 minutes that was blocked by James Tomkins.
Petrov again came close minutes later as did Elmander while Sturridge saw a close-range header taken by Green.
Petrov then skipped down the wing in the 39th minute and floated a cross into the centre that went marginally over Sturridge's head.
West Ham hit back two minutes later when Thomas Hitzlsperger tested Jussi Jaaskelainen with a shot from the edge of the box after Wayne Bridge had delivered the cross.
Bolton responded and went 3-0 ahead in the 51st minute with Sturridge's second goal of the game.
He drifted in from the left and got the better of Scott Parker on the edge of the area before steering a shot beyond Robert Green.
Sturridge came within a stride of completing his hat-trick in the 55th minute, only for Tomkins to make a vital interception.
A minute later West Ham almost pulled a goal back but Jussi Jaaskelainen reacted magnificently to somehow claw away a header from Demba Ba.
Back came Bolton and Green did well to get a hand to Sturridge's chip from close range.
However West Ham had suddenly come alive and Tomkins saw his effort in the 63rd minute blocked by Jaaskelainen.
Bolton continued to look dangerous every time they broke forward and Sturridge was again left frustrated in the 68th minute when he found the wrong side of the post with his effort.
Bolton almost added a fourth in the 83rd minute through substitute Ivan Klasnic but he failed to test Green and sent his effort wide.
The crowd were willing Sturridge to get his hat-trick but the young striker squandered a glorious chance from close range in stoppage time.