Buttler, 31, regularly deputised as captain during Morgan's seven-and-a-half-year tenure and has captained England in nine ODIs and five T20Is to date, most recently in the third ODI against the Netherlands in Amstelveen last week.
His first assignment as captain will be the T20I series against India which starts on July 7 at the Ageas Bowl, for which England are due to name their squad on Friday lunchtime. That fixture marks the start of a packed schedule of 12 limited-overs internationals in 25 days, with three T20Is and three ODIs against both India and South Africa before the end of July.
Working with new white-ball coach Matthew Mott, Buttler's primary focus will be on the T20 World Cup in Australia later this year but England's defence of their 50-over title is not far away: the next ODI World Cup is scheduled for October-November 2023 in India, with another T20 World Cup to follow in the Caribbean and the USA in 2024.
Buttler was recommended for the role by Rob Key, England's managing director of men's cricket, and his appointment was ratified on Wednesday evening by the ECB's interim chair, Martin Darlow, and chief executive, Clare Connor.
"Jos Buttler was the perfect choice to succeed Eoin Morgan as our white-ball captain, and I had no hesitation in offering him the role," Key said. "Jos has been part of our white-ball set-up for over a decade and was integral in the transformation of the way the team has played its attacking brand of cricket over the past seven years.
"He is well-respected in the dressing room by all of his teammates and will relish leading his country. He is in the form of his life and is showcasing his talent against the best players and teams in the world.
"I believe the extra responsibility will take his game to a new level and inspire those around him. I'm looking forward to seeing him take us forward. He thoroughly deserves the opportunity."
Buttler said it was a "great honour" to take over the captaincy from Morgan, offering him his "sincere thanks and gratitude" for his leadership. "It has been the most memorable period for everyone involved," Buttler said. "He has been an inspirational leader, and it has been fantastic to play under him. There are lots of things that I have learnt from him that I'll take into this role.
"There is excellent strength in depth in the white-ball squads, and I'm looking forward to leading the teams out for the series that are coming up against India starting next week and later in July against South Africa. It is the greatest honour to captain your country, and when I have had the chance to step in the past, I have loved doing it. I can't wait to take this team forward."
Connor said: "Jos is a fantastic role model who inspires through his performances on the pitch. He has been instrumental in setting new standards in men's white-ball cricket, and is the perfect leader to build on the incredible legacy which Eoin has built for our men's white-ball teams."
Buttler's appointment as captain was widely anticipated after Morgan's retirement, with Moeen Ali - the only other realistic contender - endorsing Buttler while working for the BBC's Test Match Special during the third Test against New Zealand at Edgbaston. He has been vice-captain of the white-ball sides since February 2015 and despite limited captaincy experience, he has been viewed as Morgan's heir apparent for a number of years.
Buttler shut down questions about the prospect of a Test recall during the Netherlands tour and his promotion means it is increasingly hard to work out a route back into the set-up for him, despite his remarkable white-ball form. Sam Billings has been preferred as Ben Foakes' deputy against India this week and Ben Stokes insisted on Thursday that he had "the Test team I want going forward" available to him.
"When we sat down at the start of the summer and selected the squad, it was because those were the guys we wanted in every position and they were the best players to do that," Stokes said. "At the moment, it's about giving this team time to succeed and perform.
"[Buttler] was the obvious choice once Morgs decided to retire," Stokes added. "He's been vice-captain for a number of years and nothing will change. Jos will continue the ethos and mindset that Morgs brought to us from 2015, so, honestly, I don't think you'll see anything change whatsoever. It is Jos' time to take the team forward."