Fresh from thrashing Paris Saint-Germain 4-1 in the Champions League, Newcastle suffered a first-half hangover at the London Stadium.
Tomas Soucek tapped West Ham into an eighth minute lead after brilliant play by Lucas Paqueta and Emerson down the left.
Newcastle were lucky not to then have Bruno Guimaraes sent off for a second bookable offence.
The Magpies turned the game around in a five-minute spell around the hour mark thanks to Alexander Isak’s
The Swede produced a cool finish when a free-kick into the box broke his way before taping home Kieran Trippier’s inviting volleyed cross across goal.
But Newcastle could not hold out for victory as Mohammed Kudus smashed home his first Premier League goal.
Aston Villa missed the chance to climb into the top four at Arsenal’s expense after being held 1-1 at Wolves.
The in-form Hwang Hee-chan put Wolves in front before Pau Torres quickly levelled for Villa.