Cabrera was signed to Atlantic Records in 2001. His major debut single "On the Way Down" debuted on American radio in May 2004. "On the Way Down" peaked at number 15 on the Billboard Hot 100 singles chart.

In 2004, Cabrera appeared in several episodes of the first season of singer Ashlee Simpson's reality show, The Ashlee Simpson Show. Simpson appeared in Cabrera's music video for "On the Way Down". Cabrera later opened for Simpson's older sister Jessica tour.

In 2005, Cabrera hosted the MTV series Score, in which contestants write and perform songs in order to vie for the heart of a guest on the show.

In 2006, Cabrera released the single "I Will Remember You". The song was used soon thereafter as the closing montage for the series finale of Will & Grace. Soon after, the song was used to send off the female contestants on the 3rd season of So You Think You Can Dance. He added a re-recorded version of the song at the end of his third album, The Moon Under Water.

The Moon Under Water was released on May 13, 2008, under Frolic Room Records/ Papa Joe Records and peaked at No. 177 on the Billboard 200. It released two singles, "Say" and "Enemies".

In 2010, he appeared in several episodes of The Hills during its sixth and final season. The episodes chronicled his romance and eventual break-up with Audrina Patridge. In 2010 he also appeared in the E! television show, Pretty Wild.

On July 3, 2012 Cabrera released a new song called "Home". On August 2, he released another single called "I See Love" on iTunes, where it reached No. 83 on the top 100. In January 2013, he went on a U.S. tour with Tyler Hilton and Teddy Geiger.

In March 2013, Cabrera launched the web series Live From Ryan's Living Room. Joining Ryan were celebrities including Colbie Caillat, Tyler Hilton, Chord Overstreet and Mark Ballas. Each month Ryan chose a charity to benefit, one being City of Hope National Medical Center. In September 2013, Ryan went on an Ireland and UK tour with Boyce Avenue.

In 2014, Cabrera was the first Artist signed to Dynamite Music, which was founded by Mitchell Davis and Marco Liuzzo in partnership with Caroline Records and Universal Music Group. On October 7, 2014, Cabrera announced his single "House on Fire" with a video on his Facebook page. The single was released to iTunes on October 22. He released a lyric video for his single "House on Fire" on November 3, 2014, on Artist Direct's website. "House on Fire" peaked at number one on the US dance chart. Cabrera's EP, Wake Up Beautiful, was released on March 3, 2015.

Formed in late 2015, Beyond the Sky is a musical conglomerate consisting of players, producers and vocalists from a multitude of genres. Cabrera took lead in this collaborative project, whose first single "Right on the Money" was released on February 12, 2016.