Fifth Harmony's second album 7/27 was released in May 2016. "Work from Home", the album's lead single, peaked at number four on the Billboard Hot 100, and reached the top 10 in several international charts. "Work From Home" became the first song from a girl group to reach the top 10 of the Billboard Hot 100 in eight years. The group's third album, Fifth Harmony, their first as a foursome after Cabello's departure in December 2016, was released in August 2017. The album marked the first time the group was able to co-write and have agency over the creative direction of an album. In March 2018, the group announced their decision to take an indefinite hiatus to grow as individual artists and pursue solo ambitions.
After the release of the group's second album, Jauregui continued with Fifth Harmony and began exploring solo songwriting, while the other members also worked on solo projects outside the group. In December 2016, she collaborated with Marian Hill on their song "Back to Me", Jauregui's first release outside of Fifth Harmony. Jauregui said that being able to "form a genuine connection" with the duo and write for the song was an "honor", while it gave "a snippet of my vibe for the first time in collaboration with them". Samantha Gongol of Marian Hill said that the duo and Jauregui had been wanting to work together since they met at one of Marian Hill's shows over a year earlier, and they completed the song with her in a brief period she had outside her tight schedule with Fifth Harmony. Jeremy Lloyd of Marian Hill said that Jauregui told them she had written her verse about five minutes before she was going to record it, and she "nailed the rhyme scheme and did so probably quicker and more deftly than we could have done". Lloyd also complimented the harmonies Jauregui wrote, saying that she has "an amazing harmonic ear". At the end of 2016, Jauregui was voted as the sexiest woman in AfterEllen's top 100 list of the year.
Jauregui uses her platform to raise awareness on a number of issues, including human rights, education, criminal justice, election voting, immigration, gun violence and reform, harassment, and other social issues. She is politically outspoken, involved in protests, and has partnered with several organizations and attended events that work with such causes. She has written several open letters since the 2016 United States presidential election, criticizing Donald Trump and his policies, including the "Muslim ban", calling it "disrespectful to humanity". In November 2016, Billboard published an open letter she penned to Trump voters, where she wrote about repercussions of Trump's campaign and election, and stated: "I am a bisexual Cuban-American woman and I am so proud of it". Jauregui has said she identifies with sexual fluidity. She has also spoken about LGBTQ issues.