 "Død Kalm" received mostly mixed to moderately positive reviews. Entertainment Weekly gave "Død Kalm" a B, noting that, "Despite clumsy makeup, isolation pays off again, and Mulder and Scully get to try a little tenderness." Todd VanDerWerff from The A.V. Club, despite noting his original dislike for the episode, awarded it a B rating and wrote, "This episode works, almost in spite of itself. There are so many nice little moments here [...] it's a script that pauses from the constant horror the show had been serving up for several episodes in a row to just tell an unsettling, ultimately moving tale of two friends who look into the abyss and somehow don't fall."
