Lewis Nash was born December 30, 1958, in Phoenix, Arizona, and started on drums at ten. He came to jazz by way of R&B and funk. James Brown's records, Stax singles, and Earth, Wind & Fire were his first rhythmic education, and he only worked backward into the jazz vocabulary of Philly Joe Jones, Max Roach, Art Blakey, Jimmy Cobb, Roy Haynes, Kenny Clarke, Billy Higgins, and Ed Blackwell once he was already playing. He studied broadcast journalism, then marketing, at Arizona State University while working the local scene under the guidance of Phoenix mentors including pianist Charles Lewis, arranger Prince Shell, and guitarist Jerry Byrd. By eighteen he was gigging with local jazz groups; by twenty-one he had become Phoenix's first-call drummer, backing touring names such as Sonny Stitt, Art Pepper, Red Garland, Lee Konitz, Barney Kessel, and Slide Hampton whenever they came through town, and sitting in on double bills opposite visiting groups like Old and New Dreams, Sun Ra, and the Art Ensemble of Chicago.

A chance meeting with Freddie Waits, then drumming for pianist Billy Taylor, pushed Nash toward New York. Waits recommended him to singer Betty Carter in 1980, and in 1981, at twenty-two, Nash relocated to New York and joined Carter's trio, touring internationally with her for close to four years. He is featured on three of her albums from that period, including 1988's Look What I Got (Verve), which won Carter a Grammy for Best Jazz Vocal Performance, Female. The Carter trio functioned as the era's de facto finishing school for young rhythm sections, and it put Nash's name in front of the entire New York scene almost immediately.

Through the rest of the 1980s and into the 1990s Nash became one of the most called-upon drummers in mainstream jazz. He worked steadily in Ron Carter's two-bass quintet and larger nonet (documented on 1990's Eight Plus), with Branford Marsalis, and with the Don Pullen/George Adams quartet, while building a decade-long tenure, alongside bassist Peter Washington, in the Tommy Flanagan Trio that ran from around 1990 through the end of the decade (Beyond the Bluebird, 1991; Sea Changes, 1996; and other Flanagan dates cut across the 1990s). He also became a fixture in Dizzy Gillespie's late working groups, recording To Bird with Love (1992) and, later, the posthumously released Triple Play (1998, Telarc). Most notably, Nash was one of two drummers, alongside Kenny Washington, on Gillespie's last public performances: three January 1992 nights at New York's Blue Note, cut with a rotating cast of guest saxophonists and issued in 1997, after Gillespie's 1993 death, as Bird Songs: The Final Recordings (Telarc), with George Mraz on bass. It was also in this period that Nash entered pianist Toshiko Akiyoshi's orbit, appearing on her 1990 and 1992 recordings Four Seasons and Remembering Bud . Cleopatra's Dream before joining her, Lew Tabackin, and George Mraz in 1997 for the quartet reunion album Toshiko Plays Toshiko: Time Stream (Nippon Crown), revisiting Akiyoshi's own compositions, including "Kogun" and "Farewell to Mingus," as a working unit rather than a nostalgia date.

Nash began stepping out as a leader in the late 1990s without ever slowing his sideman calendar. His debut, Rhythm Is My Business, was recorded October 5, 1989, at A&R Studios in New York with Mulgrew Miller, Steve Nelson, Peter Washington, and Ron Carter, but did not see release until 1993, on Evidence. Two more leader dates followed for the Japanese M&I Jazz label, both recorded live-in-studio in New York with Washington and vibraphonist Steve Nelson: It Don't Mean a Thing (2004) and Stompin' at the Savoy (recorded August 2004, released January 2005). His sideman work in the 2000s reached some of the format's biggest rooms: he is the drummer on McCoy Tyner's Illuminations (2004, Telarc, with Gary Bartz, Terence Blanchard, and Christian McBride), which won the 2005 Grammy for Best Instrumental Jazz Album, and on James Moody's 4B (2010, IPO Recordings), which won the Grammy for Best Jazz Instrumental Album at the 2011 ceremony. In between, he joined the Blue Note 7, the septet Blue Note Records assembled for its 2008-2009 70th-anniversary tour and the album Mosaic: A Celebration of Blue Note.

Nash has continued leading and recording steadily since. He formed a long-running duo with saxophonist Steve Wilson, documented on Duologue (recorded 2013, released 2014, MCG Jazz) and a live Umbria Jazz Winter set from the same winter, and led a quintet of Renee Rosnes, Jeremy Pelt, Jimmy Greene, and Peter Washington on The Highest Mountain (recorded live at Cory Weeds's Cellar Jazz Club, Vancouver, September 2011; released 2012, Cellar Live). Recent sideman work includes Jimmy Heath's posthumous Love Letter (2020) and Ron Carter's Grand Company (2023, with pianist Ray Gallon). Alongside performing, Nash joined Juilliard's inaugural jazz faculty in 2001, has taught at the Vail Jazz Workshop for more than two decades, and in 2017 became the Bob and Gretchen Ravenscroft Professor of Practice in Jazz at Arizona State University, his alma mater; a scholarship in his name was endowed there in 2021. The Nash, a Phoenix jazz club and education center opened in 2012 by the nonprofit Jazz in AZ, is named in his honor. Modern Drummer named him "Jazz's Most Valuable Player" in its May 2009 issue, citing an appearance count then already past 400 records; Discogs alone now credits him on more than 500 releases.

Nash's reputation rests substantially on brushwork: he is widely called one of the instrument's great brush players, working with the snares engaged for a fatter, more assertive sound than the technique's reputation for delicacy suggests, and developing a single idea patiently across a chorus rather than cycling through effects. That control extends to how he tunes his kit, setting the drums at wider melodic intervals so that a phrase moves the way a line of music would rather than reading as undifferentiated rhythm. Critics and peers describe the same quality from different angles: drummer Andrew Cyrille credited him with "dotting all the i's" in the lineage of Kenny Clarke, Ed Thigpen, and Philly Joe Jones; saxophonist Joe Lovano called his time "lyrical" in a way that makes an audience want to jump out of its seat while staying refined; saxophonist Steve Wilson, his longtime duo partner, compared his listening instincts to Billy Higgins's. Underneath the polish sits the R&B and funk vocabulary he absorbed before he ever heard bebop, which is part of why his groove reads as contemporary rather than as a period recreation of 1950s and '60s hard bop, the idiom in which he has spent most of his career.