The 25-year-old is on international duty with Brazil ahead of FIFA World Cup but will become a Manchester United player before the tournament gets underway on June 14, according to Dan King at The Sun.
Fred is expected to come in to replace Michael Carrick at Old Trafford. The 36-year-old retired at the end of the season and will join Jose Mourinho's coaching staff.
Football writer Ben Fairthorne reported the deal is all agreed and a medical has been scheduled:
Fred will spend the summer in Russia at the World Cup after being called into Tite's squad. Simon Collings at Hayters said the midfielder has looked good in training with the national team:
Fred's arrival will boost manager Jose Mourinho's options in central midfield. He is defensively sound, can carry the ball forward and boasts an excellent range of passing.
Squawka Football showed how he caught the eye in the UEFA Champions League:
Manchester United will hope he can help strengthen the team and bring an energy and creativity that was sorely lacking from the midfield towards the end of last season.
However, Bleacher Report's Sam Tighe explained how the Red Devils might struggle to fit Fred into the team:
Mourinho has work to do this summer if he is to close the gap to Manchester City and challenge for the title next season. The Red Devils may have finished second in the Premier League in 2017/18, but they were a distant 19 points behind Pep Guardiola's side and lacked the quality to compete.
Fred's arrival should help strengthen the team, but Mourinho also needs to find out how to get the best out of key players such as Paul Pogba and Alexis Sanchez if he is to catch up to City.