
The 26-year-old England forward had been linked with a move to West Ham in January, but decided to stay on, much to the delight of the club.
"We are absolutely delighted, it is fantastic news for Evertonians," Everton chairman Bill Kenwright said.
"This deal further underlines our commitment to keep our best players at our club."
"We continue to build for the future and Andrew Johnson is very much part of that future."
DPA