Jeffries was born in Sunderland, Tyne and Wear and grew up around the East Herrington area of the city whilst attending Farringdon Community Sports College. He began to box at the age of ten, inspired by his uncle William Young "Billy" Bryce, a former professional boxer. He joined Sunderland Amateur Boxing Club, and in 1999 won the School Boys' Championships, gold in the European Cadets (U17) in 2001., and won the juniors of the 2003 YMCA International Cup in New Delhi. He was also a semifinalist in the 2003 Junior Brandenburg Cup and 2003 European Junior Championships in Warsaw.
He won 9 National titles and fought for England/GB 56 times having a total of 106 fights 96 amateur & 10 professional
On 18 November 2011 Jeffries married his childhood sweetheart Emergency room nurse Sarah Kneeshaw (Sarah Jeffries) in January 2012 they both moved to Santa Monica California they have 2 daughters together.
He has a sister named Lucy Jeffries, born 26 March 1996, and sister Sarah Jeffries Briton, born 23 April 1982.
At the 2005 Commonwealth Championships he lost in the finals to Shawn Cox of Barbados, and in the quarterfinals of the 2006 Commonwealth Games he lost to Scotland's tourney winner Kenny Anderson at light-heavy (had right hand surgery after). In other open international competitions, he was a finalist in Kaunas Lithuania's 2005 Szocikas Tournament and Finland's 2005 GeeBee tournament and Bulgaria's 2006 Strandja Memorial.
At the 2007 World Amateur Boxing Championships he beat Daniel Kooij, Christopher Downs and Ramazan Magomedov in the preliminaries, but lost to Kazakhstan southpaw Yerkebuian Shynaliyev in the quarters. He did, however, qualify for the 2008 Olympics, becoming the first ever boxer from Tyne and Wear to do so. He won a bronze medal after losing to the Irish Boxer Kenny Egan in the semi-final round. Not long after he represented his medal to the Sunderland people at the Stadium of Light, being a supporter of Sunderland A.F.C.. Jeffries signed his first professional during the half-time break of Sunderlands match against Bolton Wanderers on Saturday 29 November after a row over unpaid bonuses from the Amateur Boxing Association of England
On 23 September 2012, Tony Jeffries announced on Facebook that he has retired. The numerous issues with his hands and unsuccessful surgery and treatment left him with no choice but to retire. Tony now owns and works at Box 'N Burn boxing gym in Santa Monica, Los Angeles, with Kentucky fitness expert Kevan Watson.
2007 (as a Light heavyweight)Defeated Daniel Kooij (Netherlands) 13–6
Defeated Christopher Downs (United States) 18–9
Defeated Ramazan Magomedov (Belarus) 16–8
Lost to Yerkabulan Shinaliev (Kazakhstan) 9–20
2008 (as a Light heavyweight)1st round bye
Defeated Eleider Álvarez (Colombia) 5–5
Defeated Imre Szellő (Hungary) 10–2
Lost to Kenneth Egan (Ireland) 3–10
Jeffries signed a professional contract with boxing promoter Frank Maloney in January 2009. On 27 February, Jeffries won his debut fight at super middleweight on the Munroe-Martinez undercard in a first-round knockout of Aliaksandr Vaiavoda in Barnsley.
Jeffries won his second professional fight on home soil in impressive fashion. He produced another TKO at the Crowtree Leisure Centre to defeat Roy Meissner.
Jeffries racked up five more wins before a disappointing draw with Michael Banbula in July 2010 due to a mix up in rounds, Jeffries thinking he was going into a 6-round fight but after the 6 rounds he got told he had 2 rounds left and lost the last 2 rounds and ended up drawing the fight.
After retiring from boxing when they couldn't heal his hands after major surgery in 2012, Tony Jeffries has been struggling for years with hand problems. He moved afterwards to Los Angeles where he waited for healing but it was never done. Tony Jeffries started to work in a gym in Santa Monica where he met another trainer who is from Kentucky. They left that gym and started a boxing Bootcamp on Santa Monica and they started to look for premises locally, then actor Mickey Rourke heard about the popular gym and invested in it. When some space was found Mickey Rourke changed some terms on what Tony Jeffries and the other trainer originally agreed upon so they went separate ways. The Santa Monica Bootcamp got voted Los Angeles' number 1 gym in 2013 on Yelp and the gym Box 'N Burn was busy after just a year of opening in 2014. Tony Jeffries and the other trainer opened Box 'N Burn location number 2 in Brentwood, Los Angeles. Tony got a role in the NBC TV Blacklist in 2013 and was one of the figures in Levi's world campaign in the same year. His Levi's modelling pictures where on billboards across the world. Tony is head trainer for UFC heavyweight contender Brendan Schaub, cornering him on the pay per view shows against Matt Mitrione, Travis Browne and Andrei Arlovski. He also featured in Cannonball (Skylar Grey song) video, single by Skylar Grey feat. X Ambassadors.