'Selling Sunset' Stars Mary, Emma, Chelsea & Sandra Out for Season 10

Mary Bonnet, Emma Hernan, Chelsea Lazkani and Sofia Vergara's sister, Sandra Vergara are out at "Selling Sunset" ... 'cause TMZ has learned the ladies will not be returning for season 10 of the hit Netflix reality series.

Sources connected to the series tell TMZ ... the four cast members were informed back in April that their contracts would not be renewed ahead of production on the upcoming season, which begins filming in the next couple weeks in Los Angeles.

We're told Bre Tiesi and Amanza Smith are both returning for the new season ... alongside original cast members Christine Quinn and Heather El Moussa.

The departures mark a major cast shake up for the series, which has become one of Netflix's most successful reality franchises since premiering in 2019.

We broke the story ... there are already ripple effects across the platform's real estate slate. The cast of "Selling the O.C." was recently told they won't be filming this year, but our sources said the delay has nothing to do with Orange County drama and everything to do with "Selling Sunset" taking priority in production.