Smyth was born in Cork, Ireland in 1998 but spent her formative years living in Spain. At age 14, she relocated with her family to West London, and began writing songs on ukulele. By age 17 she was involved with the NiNE8 Collective, and had begun working on original songs of her own that included minimal R&B rhythms and verses that she would sing or rap. She started sharing tracks online under the name Biig Piig around 2016, and in 2017 she gained major attention for her song "Vice City," a jazzy and atmospheric tune that included rapped verses, a sung hook, and even some scatting. The track was streamed millions of times, and Biig Piig released several other singles to follow it up.
In 2018, she issued a five-song EP entitled Big Fan of the Sesh, Vol. 1 and the next year her second EP, A World Without Snooze, Vol. 2. Both leaned into relaxed hip-hop production and showcased the more rap-oriented side of Biig Piig's style. Later that year, she signed to RCA for the release of her third EP, No Place for Patience, Vol. 3. She issued several singles throughout 2020, and in 2021 her fourth EP, The Sky Is Bleeding, arrived, upping production values and moving away from the candle-lit hip-hop sound of earlier releases for a sharper, more pop-friendly sound. The singles "FUN," "Kerosene," and "This Is What They Mean" appeared in 2022, preceding the 2023 mixtape Bubblegum, which included the Deb Never-featuring "Picking Up." ~ Fred Thomas, Rovi