The forward agreed to a one-year contract with Lokomotiv in the KHL on Tuesday, according to a report from Igor Eronko of Sport-Express.
Rattie became an unrestricted free agent when the Oilers chose not to tender the 26-year-old a qualifying offer.
There will be at least one familiar face when he joins his new club as Lokomotiv is coached by former Oilers executive Craig MacTavish.
Rattie registered five goals and nine points in 14 games late in the 2017-18 season and developed some decent chemistry with Connor McDavid after being called up from the AHL’s Bakersfield Condors.
That didn’t result in 2018-19 success though.
The 2011 second-round pick of the St. Louis Blues only managed four goals and 11 points in 50 games this past season.
Rattie spent 64 of his 99 career NHL games in an Oilers uniform.