Born in Santa Cruz, Manila, Geronimo first gained recognition after winning the television talent show Star for a Night (2002).

She signed with Viva Records in 2003 and released her debut studio album Popstar: A Dream Come True in 2003, which was supported by the singles "Forever's Not Enough" and "Sa Iyo".

[1] Her father, Delfin, was a lineman for telecommunications company PLDT, while her mother, Divina (née Tua), was educated at University of Santo Tomas, where she majored in economics.

[7][8][9] In 1995, Geronimo appeared in the film Sarah... Ang Munting Prinsesa as a background actor, playing a friend of Camille Prats's character.

[5] That same year, she appeared at the World Youth Day as a musical performer and competed in 'Sang Linggo nAPO Sila's "Princess Asia".

[22] She also starred in the film Captain Barbell, based on the superhero of the same name, in a supporting role as a younger sister of the title character (played by Bong Revilla).

[42] Geronimo next starred in the television series Pangarap na Bituin, which is loosely based on the 1986 film Sana'y Wala Nang Wakas.

[43][44] She co-starred alongside Maja Salvador and Rica Peralejo as three sisters who were orphaned and separated after their parents died in the Mayon Volcano eruption.

"[46] The Cathy Garcia-Molina-directed film A Very Special Love (2008) featured Geronimo in a lead role opposite John Lloyd Cruz.

[49][26] Film critic Karen Caliwara praised Geronimo for her acting versatility and compared her character to Anne Hathaway's roles in The Princess Diaries (2001) and The Devil Wears Prada (2006).

[52] Geronimo worked again with De Walden for her 16-track studio album, Just Me, which included a duet titled "I'll Be There" with Howie Dorough of the Backstreet Boys.

[58] Caliwara noted Geronimo with her "leading-lady charm", adding that she made a "[thrilling] pair" with John Lloyd Cruz, as with the previous installment.

"[79] The Philippine Entertainment Portal's Mark Angelo Ching lauded Geronimo's vocal abilities and stage presence, but noted that she needed improvement on her hosting.

[92] Joseph Atilano of the Philippine Daily Inquirer wrote: "[Geronimo] deliver[ed] her vocals with a sense of urgency that matches the upbeat pace of [the song].

"[92] She collaborated with her father Delfin in a cover of Carole King's "You've Got a Friend", which was also recorded by James Taylor, and co-wrote the track "Make Me Yours", along with Louie Ocampo.

[101] Her next studio album, Perfectly Imperfect, was released that year, which included the single "Kilometro", written by Thyro Alfaro and Yumi Lacsamana.

[112][113] Its lead single "Tala", was written and composed by Nica del Rosario, Emmanuel Sambayan, and Jumbo "Bojam" de Belen.

[127][128][129] An accompanying music video for "Sandata" was released in July; directed by Paul Basinillo, it features Geronimo portraying the role of three different women in different storylines.

[144] The Perci Intalan and Jun Robles Lana-directed Unforgettable (2019) featured Geronimo as an autistic woman who finds a stray dog and takes care of it, and brings it while traveling to Baguio to see her sick grandmother in a hospital.

Written by Jin Chan and produced by Su Ganade and Dylan Graham, it is described as an "ear-tweaking dance [track] that is grooving", with lyrics focusing on reliving positive experiences from the past.

[165][166][167] During the concert, she debuted the single "My Mind" in collaboration with Billy Crawford, who served as the song's co-writer and co-producer;[168] its accompanying music video was released the following year.

[165] In a 2004 interview with the Philippine Daily Inquirer, she recalled that she practiced singing with her father, and cited Jose Mari Chan's "Christmas in Our Hearts" as one of the first songs she was familiar with.

[180] Her musical inspiration varies from classic musicians like Frank Sinatra, Tom Jones, The Beatles, Elvis Presley, and the Bee Gees, to pop and R&B singers like Whitney Houston and Celine Dion.

[165] She has also cited singers Sharon Cuneta, Lea Salonga, and Regine Velasquez as role models,[5][9] adding that the latter made her realize the value of hard work in pursuing a career in music.

[184] Initially, Geronimo primarily recorded sentimental ballads,[34] and is renowned for her vocal range and belting technique, the latter of which was popularized and highly influenced by Regine Velasquez.

[40] According to the Philippine Daily Inquirer's Allan Policarpio, "The [early] years saw [Geronimo] dialing down her vocals and veering away from the [belting]-style singing that proved to be harmful to her instrument.

"[197] The Philippine Star's Patricia Esteves wrote, "That Sarah chose her own songs worked to her advantage because she was able to deliver heartfelt, soulful renditions.

"[135] According to Billboard Philippines, "[Geronimo] is a multi-talented artist who is able to successfully cross both the music and movie industries having starred in top-grossing movies and popular television shows all the while maintaining a stellar music career ... She also serves as an inspiration to many aspiring young artists and actively participates in helping shape the next generation of Filipino talents.

[h] Geronimo has also been a spokesperson for various brands, including Jollibee,[223] TNT,[224] Shopee,[225] Banco de Oro (BDO),[226] and Sun Life Financial.

[239] Her television acting credits include Sarah the Teen Princess, Bituing Walang Ningning, Pangarap na Bituin, and 1DOL.