Rico started rapping in high school and released her first mixtape, Summer’s Eve (2014), when she was in tenth grade at Charles Herbert Flowers High School. After graduating from high school, she started focusing on her music career and released two mixtapes in 2016: The Rico Story and Sugar Trap. Rico Nasty gained some prominence with her 2016 single “iCarly” which amassed over 500 thousand views on YouTube within months. She also released the single “Hey Arnold,” which was later remixed featuring Atlanta rapper Lil Yachty. The duo would later link again in 2017 for the single “Mamacita” as part of The Fate of the Furious: The Album soundtrack.

In May 2017, Rico Nasty released her fourth mixtape, Tales of Tacobella, which is her earliest commercially available release as of September 2020. Kyann-Sian Williams of NME described the mixtape as “otherworldly and synth-heavy” and noted that the mixtape proved Rico’s singing abilities. In June 2017, Kelly released her single “Poppin” which quickly garnered over five million views on YouTube. The single was also featured on the HBO television series Insecure. Kelly’s fifth mixtape Sugar Trap 2 was released in October 2017 and featured an appearance from rapper Famous Dex. Critics of Rolling Stone listed the mixtape as one of the Best Rap Albums of 2017. Rico embarked on the Sugar Trap Tour in late 2017.

The singles “Smack A Bitch”, “Poppin” and “Key Lime OG” gained prominence in early 2018; all of them meeting and exceeding 10 million YouTube views in that year. The former two songs additionally gained some popularity on the video-sharing platform TikTok after being using in various memes. “Smack A Bitch” was also ranked at No. 2 on The Fader’s list of “The 100 Best Songs of 2018”. The aforementioned influx of popularity helped Rico Nasty catch the attention of Atlantic Records, where she signed and released her sixth mixtape and major-label debut, Nasty, in June 2018. The mixtape was generally well received and landed on critics lists of publications such as Rolling Stone, Pitchfork, Stereogum, Noisey, Fact, and Spin, among several others. The mixtape’s tracks, “Bitch I’m Nasty”, “Countin’ Up” and “Rage”, were also ranked on lists of the best songs of 2018 by Paper, Highsnobiety and Pitchfork respectively. In late July, Rico Nasty embarked on her headlining The Nasty Tour to support the mixtape, playing twenty-seven different venues across North America over six weeks and completing the tour in early September.

Rico Nasty coined the term “sugar trap” early in her career and has used it as the title of her independent record label as well as two of her mixtapes. Musically, the term has simply been described as “bubbly, upbeat rap” as well as “singing and trap rapping”. Lawrence Burney of Noisey noted that sugar trap is “markedly upbeat, bubbly, and self-loving, no matter her chosen delivery”, while Kyann-Sian Williams of NME described it as a blend of “hardcore, gruff vocals” and “grungy hooks with softer, computerised beats”. Rico Nasty said that sugar trap “soft, beautiful, melodic, flowy vibes” as well as “trap music like Chicago drill music, Atlanta trap music, Memphis trap music, little bit of California trap music. I mix everything. If the sound catches my ear, I mix it.” She has also described “sugar trap” metaphorically as “a headspace”, “a way of fashion” and “a way of life”. She also described the term as a “metaphorical place”, saying “It’s like when you have a really, really bad life and shit good starts happening and you don’t know how to adapt to the good shit.” In April 2018, Rico Nasty officially trademarked the term “sugar trap”.

Rico Nasty released the non-album singles and respective music videos for “Guap (LaLaLa)” in December 2019, as well as “Roof” in January 2019. She followed them up with several more non-album singles in early 2019 such as “Sandy”, “Party Goin Dumb”, “Big Dick Energy”, “Hit That”, and “Wanna Do”. In April 2019, Rico Nasty and producer Kenny Beats supported singer Khalid during the opening night of the Free Spirit World Tour. Rico Nasty made the cover of The Fader for their Summer 2018 issue, and was the subject of a documentary produced by the publication titled Countin’ Up.

In April 2019, Rico and producer Kenny Beats released the collaborative mixtape, Anger Management, as a surprise release. The mixtape received critical acclaim and made the critics’ lists of several publications including Complex, Rolling Stone, Stereogum, Noisey, Billboard, NME, and Crack. Anger Management is arguably Rico Nasty’s most successful release to date, both commercially and critically. In April 2019, Rico Nasty performed at Coachella Valley Music and Arts Festival for the first time in her career. To support the record, Rico embarked on her “Live in Europe” tour starting in late May and ending in mid July. In June 2019, XXL announced that Rico Nasty was part of their XXL Freshman Class of 2019. She performed at New York Fashion Week in September 2019 and subsequently released the single, “Fashion Week”. Rico Nasty also performed as a headlining act at Rolling Loud in New York in October 2019.

Rico Nasty provided the original song “My Little Alien” to the soundtrack for the 2020 film Scoob! in May 2020. In June 2020, her single “Smack a Bitch” (2017) was certified Gold by the Recording Industry Association of America for selling over 500,000 units in the United States. In June 2020, Rico Nasty also released the single, “Dirty”, as part of the original soundtrack for the HBO television series Insecure. On August 7, 2020, Rico Nasty appeared alongside Colombian-American singer Kali Uchis on the song, “Aquí Yo Mando”, which will serve as the lead single from Uchis’ upcoming second studio album.

On August 13, 2020, Rico Nasty released the single “iPhone” as the lead single of her debut studio album, Nightmare Vacation. On the same day, she announced that she would be collaborating with makeup brand Il Makiage on a new makeup line. Rico Nasty made the front cover of British music magazine NME in September 2020, and told Complex that the album will be released amid “spooky season” (September – October), but not exactly on the day of Halloween. Rico Nasty released “Own It” as the second single from Nightmare Vacation on September 17. In October 2020 she became an ambassador for Rihanna’s lingerie brand Savage X Fenty, and made a cameo appearance in the Savage X Fenty Show: Vol 2. A few days later, Rico Nasty engaged in a social media campaign with children’s TV mascot Hip Hop Harry and Atlantic Records to encourage the general public to vote in the 2020 United States presidential election. She released the song “Don’t Like Me” featuring rappers Don Toliver and Gucci Mane as the third single off of Nightmare Vacation.