Beckham, who serves as co-owner of the ambitious American club has opted for Neville to replace Diego Alonso, who was relieved from his duties after a poor debut campaign.
Neville left his role as the England national women's team on Monday to assume the role and could not hide his delight to lead the vision set out by the club's ownership.
"I am incredibly delighted for this opportunity to coach Inter Miami and to work with Chris and the entire ownership group," Neville said.
"This is a very young club with a lot of promise and upside, and I am committed to challenging myself, my players and everyone around me to grow and build a competitive soccer culture we can all be proud of.
"This fantastic soccer-loving market deserves consistent performances and a winning mentality, and I look forward to getting to work."
Beckham added: "I am very happy with the leadership group we have established to lead the team as we turn the page following our inaugural season and look forward to having Chris and Phil join us soon.
"I have known Phil since we were both teenagers at the Manchester United academy. We share a footballing DNA having been trained by some of the best leaders in the game, and it's those values that I have always wanted running through our club.
"Phil has deep experience in football, as a player and as a coach at both club and international level, and over his career he has worked with many of the finest managers and players in the game.
"I know his qualities as a person, his decency, loyalty and honesty -- and his incredible energy and work ethic. Anyone who has played or worked with Phil knows he is a natural leader, and I believe now is the right time for him to join."
Inter already boast two superstar names in the team in the form of 2018 FIFA World Cup winner Blaise Matuidi and Gonzalo Higuain ahead of the 2021 season.