Mike has agreed a three-year contract with the Irish province and will move to Munster ahead of the start of the 2018/19 season.
Though the 23-year old was born in Preston, he is Irish-qualified through his maternal grandmother who hails from Tralee, Co Kerry.
Steve Diamond, Sale Sharks director of rugby, said: “It has been a really difficult decision to let Mike go with us having brought him through from being a teenager and with Mike having a year left on his contract with the club.
“However, he has aspirations to play international rugby with Ireland and we really didn’t want to stand in his way.
“Mike is a great lad and has served Sale brilliantly, making over 100 appearances. And although we would like to keep him at Sale, along with all our local talented lads, this is an exceptional circumstance and we wish him well.
“I hope all Sharks’ supporters would also wish Mike the best of luck.”
Commenting on the news, Mike said: “Obviously it was a very, very difficult decision. I’ve spent many happy years here at Sale but after lots of careful thought I just felt that it was a once in a lifetime opportunity I had to take.
“I have a strong family connections with Munster and used to go there all the time when I was younger and being eligible to play for Ireland was another big factor.
“But I will be giving absolutely everything for Sale between now and the end of the season.”