Miles will reportedly sign a three-year, $25 million deal with a player option on the final season.
Miles previously declined a $4.8 million player option to become a free agent.
Miles, 30, averaged 10.7 points and shot a career-best 41.3 percent from 3-point range last season. He has a career average of 9.8 over 12 NBA seasons with the Utah Jazz, Cleveland Cavaliers and the Pacers.
Joseph, 25, averaged career bests of 9.3 points and 3.3 assists last season in his second campaign with Toronto. He spent his first four seasons with the San Antonio Spurs and has career averages of 6.8 points and 2.5 assists.
Meanwhile, the Raptors announced Sunday they signed forward OG Anunoby to a rookie contract.
Anunoby is under contract through the 2018-19 season, with two team option years to follow. Financial terms were not disclosed.
The Raptors selected Anunoby with the 23rd overall pick in the draft last month.
The 6-foot-8, 232-pound Anunoby played two seasons at Indiana, averaging 6.8 points, 3.5 rebounds and 17.4 minutes. He totaled 48 steals and 47 blocks in 50 career games (10 starts).
Anunoby averaged 11.1 points, 5.4 rebounds and 25.1 minutes this past season. He sustained a season-ending injury to his right knee on Jan. 18 at Penn State.
Toronto also signed swingman Malcolm Miller to a two-way contract and forward Alfonzo McKinnie to a multi-year deal.
The 6-foot-7 Miller averaged 7.0 points and 3.4 rebounds in 29 games for Alba Berlin of the German Bundesliga last season. He played college basketball at Holy Cross.
The 6-foot-8 McKinnie averaged 14.9 points and 9.2 rebounds in 50 games for the Windy City Bulls of the G League last season and played in the league's All-Star game. He split his college career at Eastern Illinois and Wisconsin-Green Bay.