The 23-year-old Switzerland U21 international has put pen to a two-year deal which will keep him in East London until the summer of 2018.
Spiegel is yet to make his first-team debut for the Hammers but will continue to develop alongside Adrian and Darren Randolph as he strives to force his way into Slaven Bilic's plans in the near future.
"Everyone wants to play and I want to get more game time and show what I am about. This is an exciting time for the club and I want to stay part of the West Ham family," he told the club's official website.
"With goalkeepers you need to be a little bit more patient as only one can play but I believe I can do it. West Ham is a very good place to be at the moment and everyone can play to their best.
"It is great to work with Adrian and Darren. They have great experience and you can always learn from them. It can only make me better."
Delighted to sign new 2yr contract @whufc_official with option of 2 more. Exciting times ahead #coyi#WHUFC#keeperpic.twitter.com/JdFjkRc2rl
— Raphael Spiegel (@SpiegelRaphael) February 22, 2016