The Hammers were again unfortunate not to return to East London with all three points but will be happy with a well-earned point.
Both teams started the game well but Southampton had good chances to go ahead before half-time. Jussi Jaaskelainen denied Ricky Lambert by tipping a shot onto the post as a goal looked certain.
Following the break, Saints midfielder Gaston Ramirez put the home side a goal up when he smashed the ball past Jasskelainen after his initial strike was blocked.
Andy Carroll then equalised for the Hammers only five minutes later with a deflected low shot into Arthur Boruc’s goal.