Upon its release, "Reason" garnered attention from both Avril Lavigne's and All Time Low's fan bases, as well as music critics. The track was praised for its catchy production, sincere lyrics, and the successful blend of Lavigne's and All Time Low's musical styles. While not a mainstream chart-topper, "Reason" contributed to Lavigne's continued relevance in the pop-punk and rock genres, demonstrating her ability to collaborate with artists from different musical backgrounds.

The lyrics of "Reason" delve into themes of introspection, confusion, and longing. Lavigne and Gaskarth share vocal duties, delivering lines that reflect on a relationship's complexities and the quest for understanding and closure. The song captures the emotional vulnerability of seeking reasons for a loved one's actions, highlighting the pain and confusion that often accompany heartbreak.

"Reason" is a pop-punk and emo-influenced track that showcases Lavigne's versatility as an artist. The song features a driving guitar riff, a pulsating bassline, and a high-energy drumbeat, creating an infectious and energetic sound. Lavigne's vocals on the track are distinctive, oscillating between her signature belting and softer, more melodic sections. The chorus, featuring All Time Low's lead vocalist, Alex Gaskarth, adds a harmonious and catchy element to the song, enhancing its overall appeal.

Avril Lavigne, a renowned Canadian singer, songwriter, and musician, has been a household name in the music industry for over two decades. With a distinctive voice and a knack for crafting catchy, punk-infused pop-rock tracks, Lavigne has built a devoted fan base across the globe. In 2017, she collaborated with the American rock band All Time Low on the song "Reason," which was released as a single from her seventh studio album, "Love Sux" (2022), but initially as part of a promotional single in 2017 and variously re-released.