Berry has played 52 NRL games and scored 13 tries, but did not appear in the competition during 2026.
The injury-prone outside back managed six NSW Cup matches while trying to regain his place.
Reports linked him with Melbourne as 2026 drew to a close, but he failed a medical with the Storm.
Melbourne then pursued Adam Pompey, who joined from the Warriors.
The Warriors have confirmed Berry will stay in 2027, after CEO Cameron George expressed confidence in him.
Recruitment general manager Andrew McFadden said: "We know the player Rocco can be and we're committed to giving him every opportunity to return to his best,"
Head coach Andrew Webster said Berry is determined to return and remains in his plans: "Rocco adds so much to the team when he's fit and he's determined to be ready for next season,"
Berry's position next season is uncertain, and a strong campaign may be needed to secure a contract beyond 2027.