The song was released to iTunes in the US December 26, 2011, and was later added to the BBC Radio 1 playlist. The song was critically lauded, with critics praising Swift's breathy vocals, the simplicity of the music, and its lyrics, some citing it as a welcome return to form for Swift.
"Safe & Sound" was written by Taylor Swift, Joy Williams, John Paul White, and T-Bone Burnett. In summer 2011, Lionsgate required Burnett to record songs for The Hunger Games: Songs from District 12 and Beyond, and he subsequently corralled a range of artists, including Swift, Maroon 5, The Civil Wars, and Arcade Fire. On a fall night in 2011, Burnett and the production team, as well as Swift and The Civil Wars, came to Burnett's house in Los Angeles to write the lyrics. After two hours, the song was finished. Swift further elaborated, "The Civil Wars had a show that night in L.A., so they raced right over to T Bone's house. There's so many things he could've done production-wise to make that song bigger sonically than it is, but I think that would have possibly been a mistake. For him to have left the song as a lullaby is brilliant."
On December 22, 2011, Swift posted a portion of the song's lyrics via her Twitter account and said that "Something I’ve been [very] excited about for a [very] long time is going to be happening very soon." Four days later, the song was released digitally on iTunes Store. "Safe and Sound" is a departure of Swift from her previous country pop releases, a melancholy ballad combining elements from alternative country, and folk music. Written in the key of G major, the track has a moderate slow tempo of 72 beats per minute. Swift's vocal range on the song spans from the low-note of G3 to the high-note of D5. It accompanies an acoustic guitar in its arrangement, and, according to Matthew Perpetua from Rolling Stone, features The Civil Wars' "harmony" vocals. According to Swift, the theme of "Safe & Sound" represents "the empathy and compassion Katniss feels for Rue, Peeta, and Prim in different parts of [The Hunger Games]."
"Safe & Sound" received mainly positive reviews from music critics. Jody Rosen from Rolling Stone gave the song four out of five stars, calling it Swift's "prettiest ballad." In a review of The Hunger Games: Songs from District 12 and Beyond, AllMusic's Heather Phares picked it as one of the highlights on the soundtrack, calling it "the most crucial" track.Idolator praised Swift's "breathiness that sounds more eerie than sweet", while Jason Lipshutz writing for Billboard commended the "non-Swiftian anthem that embraces the folksiness of the soundtrack" and favored the guest appearance contributed by The Civil Wars. In a less favorable feedback, Darren Franich, and editor from Entertainment Weekly, was not impressed towards the track's lyrics and Swift's vocals, writing that "there’s no sense of triumph". He further added that "Safe & Sound" "sounds more like a funeral dirge than a victory chant, especially as the song continues with light percussion that sounds like soldiers marching to their doom."The Wall Street Journal 's Christopher John Farley agreed, opining that the song "has a rural feel, but doesn’t sound like a commercial country song."
During the first week of release, "Safe & Sound" entered the BillboardHot Digital Songs at number 19 with 136,000 digital units sold. On the Billboard Hot 100, the single debuted and peaked at number 30. Following the release of the song's music video, it re-entered the Hot 100 at number 56. In its eleventh week on chart, the song rose number 71 to number 35, prior to the release of The Hunger Games soundtrack. The track was certified double platinum by the Recording Industry Association of America (RIAA). As of November 2014, the song has sold 1.8 million copies in the United States. The track also peaked at number 31 on the Canadian Hot 100 chart. Internationally, "Safe & Sound" attained moderate commercial success. The single peaked at number 38 on the Australian ARIA Singles Chart and stayed on the chart for three weeks. It was more successful in New Zealand, peaking at number 11 on the New Zealand Singles Chart and remained for five weeks. "Safe & Sound" also charted on the UK Singles Chart at number 67.
The music video was shot in a cemetery, and the scene featuring Swift sitting atop the graves are of a real couple who died in 1853.
During the Australian leg of the Speak Now World Tour, Swift added "Safe & Sound" to the tour's setlist. Swift performed the track while sitting on a couch onstage, wearing a "sparkling, floor-length gown", which, according to Brittany Cooper of Taste of Country, was slightly reminiscent of Belle from Disney's Beauty and the Beast (1991). Cooper provided a positive feedback to the performance, writing that "[Swift] took the song with a whimsical air and gave it all the mystique you would expect from the haunting ballad."