The Davis Cup will be changed to an annual World Cup-style event next year backed by $3 billion (£2.35 billion) from Gerard Pique’s investment group.
The new format will see 12 teams qualify along with the four semi-finalists from this year and two wildcards.
The first tournament in a 25-year agreement will be staged in Madrid or Lille from November 18 to 24 after a vote by International Tennis Federation members in Florida yesterday.
The Lawn Tennis Association had opposed the changes.
Spain defender Pique, the president and founder Kosmos, said: “Today is a historic day and we are convinced that the agreement ratified by the nations certainly guarantees the future of the Davis Cup and the development of tennis at all levels.
“I would like to thank ITF President David Haggerty, the ITF Board of Directors and the entire team of ITF professionals for their work with Kosmos over the past few months and welcome a new stage in which we will continue to evolve together.
“I would also like to congratulate all those who, with their votes, have embraced this change and have seen the momentous decision that was in their hands.”