The 28-year-old has been a key figure in the centre of Gianfranco Zola's midfield and despite attracting interest from a number of clubs in the January transfer window he has decided to commit his future to the Hammers.
Speaking to the official site he said, "I am very happy, pleased and excited - especially after all the speculation in the transfer window - that I can now put that to rest and sign a new-long term contract.
"In the last few weeks, the way the club is going and the direction that the manager and the board want to go is something I want to follow.
"By signing my new contract, it says that I want to do this as well. It also says a lot about West Ham, there has been a lot of negative things written, saying there was a crisis and all of that.
"This shows that West Ham are in a position to keep their players when others want them and as a player and for the fans, that is a great thing.
"The manager showed a real desire to keep me. He sees me as a massive part of the squad and that meant a lot to me, especially when there were things being written everywhere. So I am delighted to sign."