Bergener and Armstrong were part of the main cast in season 16.
The Real Housewives of Orange County are losing two housewives.
Bergener joined the Bravo reality series in season 14 as a guest star and was promoted to main cast member in season 16. Armstrong first appeared in the 15th season before being featured as a main cast member in season 16.
"After a wild season of ups and downs, I will not be returning to The Real Housewives of Orange County," Bergener revealed on her Instagram story. "Thank you to all of the fans for all of the love and support during quite possibly the hardest year of my life."
The lawyer, whose divorce from estranged husband James Bergener was a focal point of the most recent season, is focused on her next chapter post-RHOC: "I am looking forward to brighter skies ahead, and can't wait to share what's next."
Armstrong, who filed for legal separation from husband Ryne Holliday in May, joined Bergener in the "one-and-done" club, taking to Instagram on Friday to express her gratitude for the support she's received following news of her departure.
"I loved opening up about being a working mom on Real Housewives of Orange County. I am so grateful to have had the privilege to talk about my father, my kids, and a real modern relationship on national television. My family and my work are the most important aspects of my life, so I am stepping away from RHOC and focusing on them," Armstrong wrote.
"Thank you to everyone who has reached out in support- especially from the working moms," the cosmetic dermatalogist added. "Women can really have it all if you work for it. I believe in you, and I’ll still be here to chat about it with you ♥️♥️ I love inspiring people to be their best."
"I am forever grateful for the friends I made, and the lovely people at @bravo & @evolutionmedia. Here’s to the next chapter, and I hope you’ll follow along for the journey. There are so many exciting things to come, so stay tuned," Armstrong promised.
The latest season of RHOC also starred Heather Dubrow, Shannon Storms Beador, Gina Kirschenheiter and Emily Simpson, with Nicole James appearing as a friend of the housewives.
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