[12] Media response to Alas, I Cannot Swim was favourable; aggregating website Metacritic reports a normalised rating of 73% based on 7 critical reviews.

[13] The Guardian's Caroline Sullivan called the album "unnervingly grown-up" and wrote: "Simplicity is the key: playing acoustic guitar and singing in a gentle verge-of-womanhood voice, she keeps things homespun and rootsy.

"[14] Kev Kharas of Drowned in Sound noted "Marling's skill at making one word bleed with more meaning than half a dozen or so vainglorious chorus lines",[15] while Allmusic's Stewart Mason commented on the "old-school '70s singer/songwriter vibe" of the album, focusing in particular on her "alluringly husky voice and graceful acoustic guitar".

Comparisons between Marling and Canadian songwriter Joni Mitchell were cited by many, including Andrew Murfett of The Age, Matt Connors of The Courier-Mail and Cameron Adams of The Herald Sun.

[10][17][18] In addition, "Ghosts" appeared in Australian radio station Triple J's Hottest 100 of 2008 at #43, and "Crawled Out of the Sea" was used in the final episode of the third series of Skins.