Jones, 25, has signed a deal with the Italian champions until 2031 after compatriots Djed Spence and John Stones had also made moves to the San Siro.
"After a lifetime with Liverpool, the midfielder leaves his home country for the first time, joining fellow England internationals John Stones and Djed Spence and becoming the sixth Englishman in Inter's history," Inter said.
"The time has come for a new, incredible adventure - one he can approach with the confidence that has accompanied him throughout his life," they added.
According to Italian media reports, Inter will pay 35 million euros for the Reds academy graduate.
"After 16 years, it's time to say goodbye," Jones said on Instagram to announce his departure from Anfield.
"I came here as a kid with a dream of playing for Liverpool, and I've been lucky enough to actually live that dream.
"Liverpool will be a massive part of me," he added.
Right-back Spence has also signed a deal until 2031, as has centre-back Stones, whose contract at Manchester City had ended.
Inter begin their Serie A season against Monza on Saturday.
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