Ellefson was born November 12, 1964 in Jackson, Minnesota. He is of Norwegian, German and English descent. He became an accomplished bassist and honed his songwriting skills while leading several of his own bands through the club scene of North America's Midwest region before relocating to Los Angeles.
First stint with Megadeth (1983–2002)
Other than guitarist, vocalist, and primary lyricist Dave Mustaine, Ellefson was the only constant member of Megadeth from the time of their establishment in 1983 to the group's dissolution in 2002 (Mustaine subsequently reformed Megadeth without Ellefson in 2004). To differentiate between the two Daves, Mustaine referred to Ellefson as "Dave Junior", which was often shortened to "Junior". He appeared on every album and tour from 1985's record Killing Is My Business... And Business Is Good! up until 2002's Rude Awakening. Ellefson's original playing style involved using his fingers; however, as Megadeth progressed and the music became more complex, he tended to prefer playing with a pick/plectrum. Ellefson was credited with some Megadeth songs, including "Family Tree" from 1994's Youthanasia (in the 2004 remastered collection of the CD however, the track is credited to Mustaine, Ellefson, Friedman, Menza, but Dave Mustaine credited the Rust in Peace-era line-up with the entire Youthanasia album as a tribute to the band's success at the time of the record's initial release).
Feud with Mustaine
Mustaine intended to release a solo album in 2004, which would ultimately become The System Has Failed, although due to contractual obligations, Mustaine ultimately released it under the Megadeth name. Subsequently, Ellefson and Mustaine had a severe legal disagreement over royalties and rights to Megadeth's name and back catalog resulting in Ellefson filing an unsuccessful lawsuit. Though the two once enjoyed a close friendship, considerable animosity developed between Ellefson and Mustaine to the point that on Ellefson's website, Megadeth was not mentioned in his biography, only in the discography.
In a mid-2005 podcast, Ellefson did not mention his past with Megadeth at all, instead concentrating on discussing his current projects. Mustaine felt Ellefson was unfairly using the Megadeth name when advertising an amplifier for Peavey. Mustaine claims to have had dinner with Ellefson around Christmas in 2005 to talk things through; this got them on good terms, as Mustaine has stated that they spoke on the phone numerous times afterward. In 2010 Mustaine and Ellefson agreed to keep any unresolved issues in the past and were working on building and maintaining their friendship again.
Since this time Ellefson has gone on to say that he feels "that having that time away created a realization for both of us that, while we are both productive individually, Megadeth is definitely stronger with both of us in it together."
In late 2018, he confirmed he was considered to be a Metallica bassist twice: in 1986, after Cliff Burton was killed in a bus accident, and in 2002 when bassist Jason Newsted left the band a year earlier. However he wasn't included in documentary Some Kind Of Monster and the position was taken by ex-Suicidal Tendencies/Infectious Grooves and Ozzy Osbourne bassist Robert Trujillo.
Post Megadeth career and return (2003–present)
Ellefson formed F5 following Megadeth's 2002 disbandment. The band featured Ellefson on bass, Dale Steele on vocals, Steve Conley on lead guitar, John Davis on rhythm guitar and former Megadeth bandmate Jimmy DeGrasso on drums. Their first album, A Drug for all Seasons, was released in 2005. F5 appeared in support for Disturbed in February 2006 and toured the American Mid-West in the summer of 2006. Ellefson also appeared on the new Killing Machine record Metalmorphosis in 2006 alongside DeGrasso; he has also been working with Temple of Brutality. Ellefson is currently a member of the melodic power metal band Avian which features singer Lance King. He commented in an interview with Alternative-Zine.com that "Megadeth was really just a starting point for me, creatively". Ellefson played five tracks for the Soulfly album Prophecy and also played on one track on Dark Ages. He also worked with underground emcee/Record producer Necro for his album entitled Death Rap.
Ellefson is also a member of a tribute band called Hail!. Ellefson, DeGrasso (Mike Portnoy for 2010), Tim "Ripper" Owens and Andreas Kisser formed the band in late 2008. The band was, as of April 2009, touring Europe. Ellefson participated in the Christmas Rock project Northern Light Orchestra, he performed bass on many of the 17 tracks produced by rock drummer Ken Mary and also at the live show Christmas in April Orpheum Theatre, Phoenix, Arizona.
On February 8, 2010, Ellefson received a text message from Megadeth drummer Shawn Drover, saying "if ever there was a time for you and Dave [Mustaine] to talk, now is it". Ellefson was invited to rehearse with the band. After the phone call, the news was released that Ellefson would return to the Megadeth lineup. Ellefson was quoted saying "it felt like I never left" after their first rehearsal together.
In 2013, Ellefson announced that his autobiography, entitled My Life With Deth, would be issued by American publisher Howard Books. The memoir was co-written with author Joel McIver, and features a foreword by Alice Cooper.
In 2018, it was announced that Ellefson had begun work on More Life With Deth, the follow-up to his 2013 memoir My Life With Deth, to be co-written with Ellefson's business partner, and frequent collaborator, Thom Hazaert. The book will be released on July 16, 2019, by UK based Jawbone Press, and features contributions from Alice Cooper, K.K. Downing of Judas Priest, Dan Donegan of Disturbed, Brian Welch of Korn, Mark Slaughter, Ron Keel, Jason McMaster of Dangerous Toys, Frank Bello of Anthrax, Chris Adler (Lamb of God, ex-Megadeth), Mark Tremonti of Creed and Alter Bridge, Kiko Loureiro and Dirk Verbeuren of Megadeth, actor Kristian Nairn (Game of Thrones), and more, plus a foreword by My Life With Deth co-author, and Bass Player Magazine editor Joel McIver.
Ellefson Music Productions - EMP Label Group
In October 2015 it was announced that Ellefson had launched a record label and production company, Ellefson Music Productions, also known as EMP Label Group, and would release In Your Face, the debut EP from Phoenix-based all-girl pop-punk group Doll Skin (which Ellefson also produced), in conjunction with Megaforce Records in North America, and Cargo Records in Europe. The EP was released October 30 in North America, and December 18 in Europe, and re-released as an LP titled in Your Face(Again) in March 2016 via eOne Distribution. The singles from the LP received airplay on many prominent stations in the US and Europe, including Rodney Bingenheimer's weekly show on influential LA Rock station KROQ.
Since forming in 2015, EMP Label Group has secured distribution from eOne Distribution in North America, and SPV GMBH in Europe, with the roster spread among several imprints including EMP Label Group (Ellefson Music Productions in Europe), and EMP Underground. Ellefson also appears on a recurring segment "Mandatory Megadeth" on Hazaert's Dash Radio show. In January 2017, Ellefson opened Ellefson Coffee Co. in his hometown, Jackson, Minn. . 3
In May 2019, Ellefson along with business partner Thom Hazaert formed Ellefson Films and will be producing the upcoming horror film Dwellers; written, directed by, and starring Drew Fortier. On top of producing the project, Ellefson and Hazaert will also be appearing in the film as featured cameos.