"It's baaaaack!!!! #BlondeHairDontCare," she captioned the photo, thanking New York hairstylist Serge Normant, who also appears in the shot.
Kardashian previously went lighter last Labor Day weekend with the help of colorist George Papanikolas, who said at the time that his client had been building up to the change for months. Hairstylist Chris McMillan, who did that cut, described the overall look to E! News as "Cindy Crawford-esque."
Her newest change, however, isn't a permanent one -- really, is anything? -- according to Us Weekly, which heard from a source that what we're seeing is "a wig and tons of extensions" donned for purposes of a photo shoot.
Witness: In another Instagram post Wednesday that gave a closer look at her new do, Kardashian said she was "on set" with fashion stylist Carolyne Cerf de Dudzeele. And there are a number of extensions visible in the picture above.
Real or fake -- all in the spirit of reality TV, perhaps -- her hair looked even more blond in the natural light as she headed back to her New York City digs after the shoot.