The 39-year-old took to Instagram to show off the snap during a family holiday in Aspen, Colorado.
“Copied Kendall,” she captioned a series of pictures.
Unlike her sister, Kourtney opted to add a metallic puffer jacket over her swimsuit.
The day prior, Kendall braved the winter weather to take snaps of herself in a pink bikini, holding a coffee mug and sporting a snow hat.