The brief Pramac announcement officially ends what had been tipped as a dream partnership for the Englishman - returning to Marc VDS, where he had fought for the Moto2 title, on factory class Honda machinery.
But Redding and his newly assembled crew have rarely been able to gel with the RC213V and a best result of seventh is no better than he managed as a rookie on an Open class Honda.
The #45 has scored less than half the points compared to this time last season and is just 14th in the world championship, five places behind LCR Honda's Cal Crutchlow.
"We are happy to welcome Scott in the Ducati family," said Ducati Corse sporting director Paolo Ciabatti. "He's going to be racing for Ducati Pramac Team next year with the latest GP15 bikes. So we're glad and we hope to put in the conditions to show his real potential.
"We've been following Scott from his Moto2 career and in his debut season with Gresini in MotoGP. We approached him last year, but then his team decided to move to MotoGP and it was not possible. We discussed with him again around the Brno weekend and we decided that this time was the right time."
Marc VDS are now expected to promote reigning Moto2 champion Esteve Rabat to take Redding's place, with Franco Morbidelli set for Rabat's Moto2 seat alongside Alex Marquez.
Redding's very first MotoGP laps came during a successful private Ducati test in 2012, alongside Moto2 rival Andrea Iannone, who now rides for the official team.
The Englishman has been sporadically linked to Pramac/Ducati ever since that test, although his MotoGP chance ultimately came with Gresini, where he finished twelfth in last year's world championship as the top Open Honda.
Redding was again on the Pramac 'possible' list when Gresini moved to Aprilia for 2015. However he decided to reunite with Marc VDS, as his former Moto2 team took over Gr esini's factory Honda for a move to the premier-class.
With Danilo Petrucci remaining at Pramac, Redding will take the place of Yonny Hernandez, who is likely to move to Avintia Ducati. Pramac will run GP15 machinery next season, as currently used by Iannone and Andrea Dovizioso, during MotoGP's first year of Michelin tyres and a standard ECU.
Moto3 title leader Danny Kent had also been in contention for the Pramac ride, being offered a three-year deal, but Redding emerged as favourite after Brno.
