Antonio, 30, whose previous deal was due to expire at the end of this season, has committed himself to the Hammers long-term.
“I’ve been here for five and a half years, this season will be six and by the time my contract expires it will be eight years,” Antonio told West Ham TV.
“Before I signed here, the longest I had been at a club was two years, so it shows that I’ve been here, done my work, been able to secure my position and keep growing as a player.”
Antonio joined West Ham in 2015 from Nottingham Forest for what now looks a bargain £7million.
The south Londoner, who began his career with non-league Tooting and Mitcham, has made 161 appearances for the Hammers and scored 41 goals.
Antonio’s form after the restart, having been converted from a winger to a striker by manager David Moyes, really caught the eye.
He scored eight goals in six Premier League matches, including all four in the 4-0 win at Norwich.
This season Antonio has been hindered by a hamstring problem but has still found the net three times in seven appearances.
Additional reporting by PA.
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