The duo are just in time to help viewers get used to new detectives played by Danny Pino ('Cold Case') and Kelli Giddish (NBC's short-lived 'Chase').
Executive producer and new showrunner Warren Leight confirmed the casting news.
No word on how many episodes will feature the two ADAs.
March has played Alex Cabot off and on since 2000. When Cabot departed the series, Diane Neal's Casey Novak filled the ADA role for six seasons before leaving the series.
A representative also confirmed that Mariska Hargitay will appear in all 22 episodes of Season 13. Ice-T and Richard Belzer have also signed on to reprise their roles. Christopher Meloni, as previously announced, will not return to the hit NBC series.
Tell us: Are you happy to see Stephanie March and Diane Neal return to 'SVU'?