The centre has not featured for his country since last year's tournament and missed nine months of action due to an ankle injury.
However, Joseph returned for club side Bath this weekend and the 27-year-old – who has scored more tries in Eddie Jones' tenure than any other England player – will travel to Portugal on Wednesday with the rest of the squad.
Joseph has 17 tries in 40 matches for England, who begin their Six Nations in Dublin on February 2.
