The hand-off will take place at the16th Annual Screen Actors Guild Awards, to be simulcast live on TNT and TBS on Saturday, Jan. 23, from Los Angeles's Shrine Exposition Center. (Check local listings for time, including that of the encore presentation.)
The two starred together in 2009's box-office hit, the romantic comedy The Proposal. White played the spiritual Alaskan grandmother of Bullock's love interest (and coerced fiancé), Ryan Reynolds.
White, 87, can practically boast of a lifetime on TV. Her six decades' worth of work – which have resulted in 18 Emmy nominations and six actual awards, so far – include her riotous turn as happy homemaker Sue Ann Nivens on The Mary Tyler Moore Show (1973-77) and as the often-vague Rose Nylund on The Golden Girls (1985-92). She also rode the early I Love Lucy domestic-sitcom bandwagon as the star of 1953's Life with Elizabeth.
Her next role will be in the Disney feature You Again, with Kristen Bell, Jamie Lee Curtis, Sigourney Weaver and Kristin Chenowith. Offscreen, White is a passionate animal-rights activist, affiliated with such groups as Actors and Others for Animals and the Morris Animal Foundation.
Bullock, 45, is also up for a SAG Award – named The Actor – for her leading role as the real-life Leigh Anne Tuohy in another box-office hit from last year, The Blind Side.
Past recipients of SAG's Life Achievement Award include James Earl Jones, Julie Andrews, Clint Eastwood, Sidney Poitier, Elizabeth Taylor, Angela Lansbury and Robert Redford.
Watch the SAG Awards on Jan. 23, live on TNT and TBS – and catch up on all the news and style from the show on PEOPLE.com!