While in the Army Carl started training at the Grapplers Lair, after two months of training and no amateur fights Carl made his professional debut on November 5, 2005 against Andrew Perkins, winning the fight via submission. Carl went undefeated at 5-0 before taking his first loss to future UFC fighter, Brian Foster. Carl rattled off seven consecutive wins, six of which were finishes, before being signed by Bellator.
Bellator
Carl made his debut for the promotion on April 22, 2010 at Bellator 15 in the. He was matched against Brett Cooper and after three close rounds, Carl won the fight via split decision. In the semi-final round Carl was matched against Sengoku veteran, Dan Hornbuckle, at Bellator 19. Carl lost the fight midway into the first round via submission, eliminating him from the tournament. Carl took an off-tournament fight against Tyler Stinson at Bellator 26. Midway into the first round Carl applied a guillotine choke and choked Stinson unconscious. The impressive win earned him entry into the next season Welterweight Tournament. However, Carl injured his foot and was unable to compete in the tournament. Carl entered into the, and was matched against the tournament favorite Douglas Lima. The fight took place at Bellator 49. Carl lost the fight via unanimous decision. Carl was released from the promotion after the loss.
Post-Bellator
In December 2011 Carl made his post-Bellator debut fighting for Far Eastern Federation of Modern Pankration in Russia. He defeated Rustam Bogatirev via submission in the first round. On March 2, 2012 Carl fought Mason Temiquel, taking the fight on only one day's notice, winning via submission and then on July 28, 2012 later defeated Vic Hall via submission, both in the first round. Carl defeated Andrew Trace via first round submission at Madtown Throwdown on August 11, 2012.
In late 2012, Carl signed with upstart Las Vegas promotion World Series of Fighting. His debut came at the promotion's first event, World Series of Fighting 1, held on November 3, 2012 against Ramico Blackmon. Steve Carl won the fight via rear naked choke submission in the first round. Steve Carl defeated Tyson Steele on June 14, 2013 at via rear-naked choke submission in round one. Steve Carl fought Josh Burkman and won via triangle choke submission in the fourth round at to become the first WSOF Welterweight Championship. Carl made his first title defense at WSOF 9 on March 29, 2014 against UFC vet Rousimar Palhares. He lost the bout due to submission in the first round.
