Undertow has a 100% approval rating on Rotten Tomatoes.[8] Luke Buckmaster of The Guardian gave it four stars and called it “an intensely gripping female-led Australian drama”.[9] Sarah Ward of Screen Daily said “Making a moody, confident feature debut, actor turned writer/director Miranda Nation takes the drama of mourning and impending motherhood, and spins it into psychological thriller territory with an added dose of topicality.”[10] Vicky Roach of the Daily Telegraph gave it 3 stars, calling it "An impressive showcase for some extraordinary Australian talent."[11] Writing in the Canberra Times, Jane Freebury gave it 3 stars, concluding "Undertow is in many ways an impressive achievement, and it augurs well for director Nation's next project."[6]David Stratton gave it 3 stars in The Australian. He states "The plotting is convoluted and the motivations not always clear, but the film gets by on the strength of some solid performances and the attractive photography by Bonnie Elliott."[12] The Sun Herald's Sandra Hall gave it 3 1/2 stars, finishing her review "It's an intelligent film, but it's relentless."[13]