US broadcaster Bravo confirmed that Kathy will join the reality show as a “friend of the housewives”, meaning she will make recurring appearances throughout the series.
Kathy will join her younger sister, original Housewife Kyle Richards, on the show. Their sister Kim has also appeared in previous seasons.
“She's not just a Friend Of — she's family! Please welcome @kathyhilton to #RHOBH,” Bravo announced on Instagram.
Kathy’s complicated relationship with Kyle has provided a source of drama on the show in previous seasons.
Kathy and Kim both objected to their sister telling what they called a “fictionalised” version of their childhood, in the short-lived drama series American Woman. The show starred Alicia Silverstone as a version of the Richards sisters' mum.
All three siblings now appear to be on better terms.
The new season of The Real Housewives of Beverly Hills will also star new fulltime Housewife, actor and food entrepreneur Crystal Kung Minkoff, who will replace Denise Richards.
Paris Hilton recently released her own TV project, a YouTube documentary exploring her public persona as one of the ultimate “It Girls”.
The Real Housewives of Beverly Hills is available to watch on NOWTV in the UK, and Bravo in the US.