It is not yet known where Couper has moved to.
She has not been responsible for Expedia brand communications for the last five years, having latterly been responsible only for Hotels.com, a brand of the Expedia Group.
A spokesperson for Expedia internal communications said: "We can confirm that Alison Couper is no longer with Hotels.com or Expedia Group.
"Alison leaves us with our heartfelt thanks for her great efforts and our very best wishes for the future."
Couper joined Expedia in 2004. Prior to this she was a comms director at British Airways and TV Travel Shop.