Born Lamont Coleman in Harlem, New York on May 30, 1974, he was the third and youngest child of Gilda Terry (d. 2008) and Charles Davis. His father left the family while Big L was a child. He has two siblings, Donald and Leroy Phinazee (d.2002), who were the children of Gilda Terry and Mr. Phinazee. Big L received the nicknames “Little L” and “‘mont ‘mont” as a child. At the age of 12, he became a big Hip Hop fan and started freestyling against his own neighborhood. He founded a group called Three the Hard Way in 1990, but was quickly broken up due to a lack of enthusiasm. It consisted of Big L, a “Doc Reem”, and a “Rodney”. No studio albums were released, and after Rodney left, the group was called Two Hard Motherfuckers. Around this time, people started to call him “Big L”. In the summer of 1990, Big L met Lord Finesse at an autograph session in a record shop on 125th Street. After he did a freestyle, Finesse and Big L exchanged numbers.

Big L attended Julia Richman High School. While in high school, he freestyle battled in his hometown; in his last interview, he stated, “in the beginning, all I ever saw me doing was battling everybody on the street corners, rhyming in the hallways, beating on the wall, rhyming to my friends. Every now and then, a house party, grab the mic, a block party, grab the mic.” He graduated in 1992.

Big L began writing rhymes in 1990. In 1991, he recorded various demos, some of which were featured on his debut album Lifestylez ov da Poor & Dangerous, he also founded the Harlem rap group Children of the Corn (COC) with Killa Cam, Murda Mase, and Bloodshed. (COC folded when Bloodshed died in a car accident on March 2, 1997.) On February 11, Big L appeared on Yo! MTV Raps with Lord Finesse to help promote Finesse’s studio album Return of the Funky Man. Big L ‘s first professional appearance came on “Yes You May (Remix)”, the B-side of “Party Over Here” (1992) by Lord Finesse, and his first album appearance was on “Represent” off of Showbiz & A.G.’s Runaway Slave (1992).

Also in 1992, he won an amateur freestyle battle, which consisted of about 2,000 contestants and held by Nubian Productions. In 1993, Big L signed to Columbia Records. Around this time, he joined Lord Finesse’s Bronx-based hip hop collective Diggin’ in the Crates Crew (DITC) which consisted of Lord Finesse, Diamond D, O.C., Fat Joe, Buckwild, Showbiz, and A.G.

Sometime in 1993, Big L released his first promotional single, “Devil Son”, and claimed it was the first horrorcore single released. He said he wrote the song because “I’ve always been a fan of horror flicks. Plus the things I see in Harlem are very scary. So I just put it all together in a rhyme.” On February 18, 1993, Big L  performed live at the Uptown Lord Finesse Birthday Bash at the 2,000 Club, which included other performances from Fat Joe, Nas, and Diamond D.

In 1994, Big L released his second promotional single “Clinic”. On July 11, 1994, he released the radio edit of “Put It On”, and three months later the video was released. In 1995, the video for the single “No Endz, No Skinz” debuted, which was directed by Brian Luvar.

His debut studio album, Lifestylez ov da Poor & Dangerous, was released in March 1995. The album debuted at number 149 on the Billboard 200 and number 22 on Top R&B/Hip Hop Albums. Lifestylez would go on to sell over 200,000 copies as of 2000. Three singles were released from the album; the first two, “Put It On” and “M.V.P.”, reached the top twenty-five of Billboard‍ ’s Hot Rap Tracks and the third “No Endz, No Skinz” did not chart. Even though the album received a three-star rating from Allmusic, it was an AMG Album Pick.

In 1996, Big L was dropped from Columbia mainly because of a dispute concerning Big L’s rapping style and the production from Columbia. He stated “I was there with a bunch of strangers that didn’t really know my music.” In 1997, he started working on his second studio album, The Big Picture.

Big L  appeared on O.C.’s single “Dangerous” for O.C.’s second album Jewelz. In November, he was the opening act for O.C.’s European Jewlez Tour. Sometime in 1998, Big L  formed his own independent label, Flamboyant Entertainment. According to the The Village Voice, it was “planned to distribute the kind of Hip Hop that sold without top 40 samples or r&b hooks.” He released the single “Ebonics” in 1998. The song was based on “Ebonics”, and The Source called it one of the top five independent singles of the year. DITC released their first single, “Dignified Soldiers”, that year.

Big L  caught the eye of Damon Dash, the CEO of Roc-A-Fella Records, after the release of “Ebonics”. Dash wanted to sign Lamont to Roc-A-Fella, but Big L  wanted his crew to sign. On February 8, 1999, Big L, Herb McGruff, C-Town, and Jay-Z started the process to sign with Roc-A-Fella Records as a group called “The Wolfpack”.

On February 15, 1999, Big L was killed at 45 West 139th Street in his native Harlem after being shot nine times in the face and chest in a drive-by shooting. Gerard Woodley, one of Big L’s childhood friends, was arrested in May for the crime. “It’s a good possibility it was retaliation for something [Big L’s] brother did, or [Woodley] believed he had done,” said a spokesperson for the New York City Police Department. Woodley was later controversially released, and the murder case remains unsolved.

In a 2010 interview with Donald Phinazee, he commented on what led up to the death of Big L:

“There was something that went down with a dude out here with my middle brother, “Big Lee” (Leroy Phinazee), and, uh, Lee went upstate for five years. […] It was a little problem like I just said, “divide and conqueror” with the fellas between all of us, and, uh, [Lee] went upstate, then I went upstate, and then [Lee] sent word to do something [to someone]. He sent word to somebody else to do something, but Lamont went with him, which Lamont shouldn’t have went with him. […] It didn’t go down the way it was supposed to have went down and they seen Lamont face. […] So, uh, both of us is gone, and [Lamont] was out here by hisself. And so you can’t get one brother, you get the other one. That’s it in a nutshell.” – Donald Phinazee

Big L is buried at George Washington Memorial Park in Paramus, New Jersey.

The tracks “Get Yours”, “Way of Life”, and “Shyheim’s Manchild” b/w “Furious Anger” were released as singles in 1999 for DITC’s self-titled album (2000) on Tommy Boy Records.  The album peaked at number 31 on R&B/Hip Hop Albums and number 141 on the Billboard 200. Big L’s first posthumous single was “Flamboyant” b/w “On The Mic”, which was released on May 30, 2000. The single peaked at number thirty-nine on the Billboard Hot R&B/Hip Hop Songs and topped the Hot Rap Tracks, making it Big L’s first and only number-one single.

Big L ‘s second and final studio album, The Big Picture, was released in August 1, 2000 and featured Fat Joe, Guru of Gang Starr, Kool G Rap, and Big Daddy Kane among others. The Big Picture was put together by his manager and partner in Flamboyant Entertainment, Rich King. It contains songs that he had recorded and a cappella recordings that were never used, completed by producers and guest emceess that Big L  respected or had worked with previously. The Big Picture debuted at number thirteen on the Billboard 200, number two on Top R&B/Hip Hop Albums.  The album was certified gold a month later for shipments of 500,000 copies by the RIAA. The Big Picture was the only music by Big L to appear on a music chart outside of the United States, peaking at number 122 on the UK Albums Chart.

A compilation album containing COC songs entitled Children of the Corn: The Collector’s Edition was released in 2003. The next posthumous album released was 139 & Lenox, which was released on August 31, 2010. It contained previously unreleased and rare tracks. It was released by Rich King on Flamboyant Entertainment. The next album to follow was Return of the Devil’s Son (2010), which peaked at number 73 on R&B/Hip Hop Albums. Big L ‘s next release was The Danger Zone (2011), and an album called L Corleone was released on February 14, 2012.