Miguel has been in a relationship with model Nazanin Mandi since 2005. In January 2016, it was announced that they are engaged.

Miguel signed a production deal with Drop Squad in 2000. In 2004, he auditioned to be part of the group Fatty Koo, but their label, Columbia Records chose someone else to complete the sextet. Later in 2004, Miguel was signed by independent record label Black Ice and started working on his studio album, Young & Free. It was scheduled to be released on November 30, 2006, but was ultimately shelved. Black Ice released the single "Getcha Hands Up" with a video debut on 106 & Park, but Miguel decided to change his sound and image and walked away from Black Ice Records. He later said in an interview for LA Weekly, "We shot a video, and if you ever see it, you will laugh your ass off. I have a fitted hat on and a white T-shirt and baggy jeans. I was 19 years old and it was the first time anyone had ever given me money."

After his protracted contract dispute with Black Ice was settled, All I Want Is You was released in November 2010. It initially performed poorly, debuting at number 109 on the Billboard 200 on 11,000 copies sold, and was underpromoted by Jive, amid the label's dissolution. The album's title track attained radio airplay, while Miguel toured as a supporting act for Trey Songz and Usher. Its following two singles, "Sure Thing" and "Quickie", performed well on the charts, After falling off the chart for three weeks, All I Want Is You became a sleeper hit, as it re-entered the Billboard 200 and climbed the chart for 22 weeks, before peaking at number 37 on May 14, 2011. It ultimately spent 45 weeks on the chart, and sold 404,000 copies in the US.

After Jive was shut down and absorbed by RCA Records, Miguel was moved to RCA, where Pitts was named President of urban music, and received a new marketing team. His second studio album, Kaleidoscope Dream, was released on October 2, 2012, to critical acclaim. The album debuted at number three on the Billboard 200, selling 71,000 copies in its first week. As of February 2013, Kaleidoscope Dream has sold 322,000 copies, according to Nielsen SoundScan. In February 2013, he released a politically driven video for the song "Candles in the Sun." The album's lead single "Adorn", which had been released on August 7, became a sleeper hit on urban radio. It was Miguel's second number-one single on the Hot R&B/Hip-Hop Songs, and his highest charting single on the Billboard Hot 100 at number 17. By September, the single had sold 190,000 copies. According to NPR's Audie Cornish, Miguel "broke through to a national audience in 2012" with both "Adorn" and Kaleidoscope Dream. The second single "Do You..." was released on September 18, and reached number 32 on the Hot R&B/Hip-Hop Songs. On March 3, 2013, "How Many Drinks?" was released as its third single. By February 20, Kaleidoscope Dream had charted for 20 weeks on the Billboard 200 and sold 321,400 copies, according to Nielsen SoundScan.

In August 2013, the new single "#Beautiful" with Mariah Carey became Miguel’s third million-seller in the USA, following “Sure Thing” and “Adorn”. During an energetic performance of "Adorn" at the Billboard Music Awards on May 19, Miguel failed in an attempt to leap across the stage, injuring two audience members in the process. Barely missing the stage, Miguel landed on two women, hooking his right leg over one and knocking the other into the stage. The incident, known as the "Miguel Leg Drop," became an immediate internet sensation and has been satirized in numerous internet memes and gifs. It has also been the subject of controversy, with the show's producers claiming that they had denied the singer permission to attempt the leap, while Miguel's representatives have countered that no objections were raised during earlier rehearsals. Khyati Shah, one of the two women involved, has since claimed she suffered a traumatic head injury that was not sufficiently attended to by show organizers.

For nearly a year, Miguel's manager at the time submitted several songs to music mogul Mark Pitts; after receiving a song titled "Sure Thing"—which Miguel described as a "highly personal ... record that no one was ever supposed to hear"—Pitts scheduled a meeting with Miguel in October 2007. The following month, Miguel signed a recording contract with Jive Records. Miguel recalled that the signing of his contract took place in a "very small room in a very small office in a small corner of the building at Jive". After being signed, he recorded his debut album All I Want Is You, but was sued by Black Ice for breach of contract. Consequently, his album was not released for two years. In 2007, Miguel also contributed vocals to three tracks on the debut collaborative project of Blu and Exile, Below the Heavens, appearing under the moniker "Miguel Jontel".

Miguel released his third studio album titled Wildheart on June 30, 2015. In December 2014, Miguel released a 3-track EP entitled NWA.HollywoodDreams.Coffee in promotion for the album. The album was nominated for a Grammy in the category Best Urban Contemporary Album, also "Coffee" was nominated for Best R&B Song. In 2016, Miguel released the single "Waves" that's been remixed by RAC and Tame Impala.

As of September 2016, he is an opening act for Sia's Nostalgic for the Present Tour. The tour runs until November 6.

Miguel's fourth album, War & Leisure, was released on December 1, 2017. He describes the album as having "political undertones, because that’s what life feels like right now".

Miguel has said that Transcendental Meditation is the key to balancing his lifestyle: "It’s good to take a breath from everything and just center yourself. That is the best way of describing it."