After a drab first half, Player of the Season Wilfried Zaha capped a fine campaign by opening the scoring with his ninth goal of the season, before Patrick van Aanholt netted for the third game in succession to secure the points for Roy Hodgson’s team.
In textbook final day of the season conditions with the sun shining and fans decked out in t-shirts, Palace started positively and nearly found a way in front after seven minutes when Luka Milivojevic played a one-two with Yohan Cabaye to create a sight of goal, but was unable to extend his lead at the top of the Eagles' goalscoring charts as he slammed his shot just wide.
Albion, playing only for pride after their relegation had been confirmed earlier in the week, also saw a Grzegorz Krychowiak shot meet the same fate not long after, but that would be as threatening as they would be throughout a quiet contest that had an end-of-season feel to it.
Palace controlled proceedings from then on but during the first half they couldn't create many more dangerous moments themselves, although they did force Ben Foster into a smart save on 18 minutes when Aaron Wan-Bissaka stole the ball from Ahmed Hegazi on the touchline and found James McArthur in the box, and he squared for Zaha who saw the former England international save his snapshot with his feet.
That was as good as the first half got, but the Eagles started the second much sharper and it was one-way traffic for the majority of it. Early into proceedings after the restart Zaha cut back for Ruben Lotus-Cheek but the midfielder couldn’t quite end his loan spell with a goal as he shot straight at Foster, and minutes later Zaha screwed wide after connecting with a Van Aanholt pass.
They then carved out a golden chance on 62 minutes when Andros Townsend found Zaha on the halfway line who slipped past Craig Dawson and sped towards the box, and he unselfishly returned the ball to his strike partner who was faced with only Foster to beat, but Townsend fired well wide.
But with 20 minutes to go, the deadlock was broken. Once again focussing their attacks down the left, Loftus-Cheek drove from halfway and fed Van Aanholt on the left flank, and his centre was side-footed home from eight yards out by a gleeful Zaha to register his fifth in his last six Premier League games.
After that it was just a case of how many the Eagles wanted to end their season with, and with 12 minutes to go they doubled their lead with another well-worked, intricate team goal. Cabaye picked up the ball in a good area and found Townsend, and he played a one-two with Loftus-Cheek on the edge of the box before slipping in Van Aanholt, and the Dutchman rounded Foster before finding enough pace on his shot for it to creep over the line, despite the despairing efforts of Hegazi on the line.
With the points in the bag, Pape Souare was handed his first Premier League appearance since September 2016 as a late substitute as the curtain came down on another remarkable, and ultimately successful, season in SE25.
Palace: Hennessey, Wan-Bissaka, Sakho, Tomkins, Van Aanholt (Souare 81), McArthur (Benteke 68), Cabaye, Milivojevic, Loftus-Cheek, Townsend (Lee 86), Zaha. Subs not used: Speroni, Kelly, Schlupp, Riedewald.
West Brom: Foster, Nyom, Dawson, Hegazi, Gibbs, Brunt, Krychowiak (Chadli 63), Livermore, McClean, Rodriguez (Sturridge 74), Rondon (Robson-Kanu 71). Subs not used: Myhill, McAuley, Field, Burke.