The Auckland-born centre-back has been a first-team regular for Sam Allardyce's side for the past two seasons, helping them gain promotion from the Championship before establishing themselves in the Premier League.
The New Zealand international, who has also captained the Hammers on occasion this season, signed a deal keeping him at the club until 2015.
|WEST HAM LATEST
|16/5||West Ham are 16/5 with PaddyPower to beat Newcastle to nil
"I think I have played some good football over the last two years but that goes for the whole team as well. Hopefully we can continue that. Of course, we now plan to build on the last two seasons."
Reid arrived at Upton Park from Danish Superliga club FC Midtjylland in summer 2010, having impressed in his displays for the New Zealand at World Cup 2010 in South Africa.
After securing his future, the defender is now looking forward to the prospect of the impending move to the 54,000-capacity Olympic Stadium.
"It is an exciting time for the club," he added. "The fans have a chance to give their opinions and ideas this week with the consultation which is really important.
"They are the ones who back us week after week and I am sure, even though it is three years down the road, they are already looking forward to seeing what can be done when we move there."