2021 was the fifth year in the history of Legacy Fighting Alliance, a mixed martial arts promotion based in the United States.
 In 2021, LFA organized a Middleweight tournament that will crown the Middleweight champion. 
 Legacy Fighting Alliance 97: Browne vs. Estrázulas is the ninety-eighth event of Legacy Fighting Alliance and will take place on January 15, 2021. It aired on UFC Fight Pass.
 The event was headlined by a fight between Nick Browne and Arthur Estrazulas, for the vacant LFA Lightweight title.
 In the co-main event, the former LFA Lightweight title challenger Jacob Rosales faced Jose Martinez.
 Legacy Fighting Alliance 98: Fremd vs. Oliveira is the ninety-ninth event of Legacy Fighting Alliance and will take place on January 29, 2021. It aired on UFC Fight Pass.
 The event was headlined by a middleweight bout between Josh Fremd and Bruno Oliveira, which serves as the first middleweight tournament semi-final. 
 Legacy Fighting Alliance 99: Dennis vs. Cherant is the hundredth event of Legacy Fighting Alliance and will take place on February 12, 2021. It aired on UFC Fight Pass.
 The event was headlined by a fight between Myron Dennis and Fabio Cherant for the LFA Light Heavyweight Championship.
 Legacy Fighting Alliance 100: Altamirano vs. Smith is the hundredth-first event of Legacy Fighting Alliance and took place on February 19, 2021. It aired on UFC Fight Pass.
 The event was supposed to be headlined by a flyweight bout between LFA's all-time wins leader Victor "El Magnifico" Altamirano and top undefeated Brazilian prospect Carlos "Tizil" Mota. The co-main event will showcase the second middleweight tournament semi-final between LFA standouts Anthony "SugaFoot" Adams and Gregory "RoboCop" Rodrigues. However, on February 13, Carlos Mota was pulled from the fight and replaced by Nate Smith. 
 Legacy Fighting Alliance 101: Kalani vs. Cummins is the hundredth-second event of Legacy Fighting Alliance and took place on March 12, 2021. It aired on UFC Fight Pass.
 LFA 101 was headlined by a bout between two middleweight prospects: Maika Graf and the undefeated AJ Dobson.
 Legacy Fighting Alliance 102: Souza vs. Johns is the hundredth-third event of Legacy Fighting Alliance and took place on March 19, 2021. It aired on UFC Fight Pass.
 The main event featured a featherweight showdown between LFA standouts Bruno "The Tiger" Souza vs. Elijah "Baby" Johns. The co-main event showcased the second middleweight tournament semi-final bout between Dana White's Contender Series alumni Gregory Rodrigues and Al "Sweetness" Matavao.
 Legacy Fighting Alliance 103: Carlyle vs. Dagvadorj is the hundredth-fourth event of Legacy Fighting Alliance and took place on March 26, 2021. It aired on UFC Fight Pass.
 The event was headlined by a lightweight bout between the UFC veteran Spike Carlyle and the one-time LFA Welterweight title challenger Batsumberel Dagvadorj.
 Legacy Fighting Alliance 104: McKenzie vs. Phillips is the hundredth-fifth event of Legacy Fighting Alliance and took place on April 16, 2021. It aired on UFC Fight Pass.
 The event was headlined by a lightweight contest between Aaron McKenzie and Brandon Phillips.
 Legacy Fighting Alliance 105: Rodriguez vs. Gotsyk is the hundredth-sixth event of Legacy Fighting Alliance and took place on April 23, 2021. It aired on UFC Fight Pass.
 The event was headlined by bout for the LFA Women's Strawweight Championship between Svetlana Gotsyk and Piera Rodriguez.
 Legacy Fighting Alliance 106: Silveira vs. Viana is the hundredth-seventh event of Legacy Fighting Alliance and took place on April 30, 2021. It aired on UFC Fight Pass.
 A light heavyweight bout between Joshua Silveira and Rafael Viana served as the main event.
 Legacy Fighting Alliance 107: Kirk vs. Swain is the hundredth-eighth event of Legacy Fighting Alliance and took place on May 14, 2021. It aired on UFC Fight Pass.
 The main event featured  a middleweight showdown between two of the most accomplished fighters in the division. Rafael Carvalho, former Bellator Middleweight Champion, faced emerging Tajik, Sharaf Davlatmurodov, who was riding a 5-fight win streak, which includes a win over Bellator middleweight tournament runner-up Brett Cooper.  The day after the announcement of the bout, it was announced that Carvalho was to face Lorenz Larkin at Bellator 258.
 Legacy Fighting Alliance 108: Fremd vs. Rodrigues is the hundredth-ninth event of Legacy Fighting Alliance and took place on May 21, 2021. It aired on UFC Fight Pass.
 The main event featured a middleweight title fight between two of the most exciting knockout artists in the division. Josh Fremd (7-1) and Gregory Rodrigues (8-3) both earned their shot at the LFA Middleweight Championship by advancing to the finale of the LFA Middleweight Tournament, which began in January. 
 At weigh-ins, Clayton Carpenter came in at 128.6 pounds, 2.6 pounds over the non-championship flyweight limit. Therefore, the fight continued at catchweight and he was fined a percentage of his purse.
 Legacy Fighting Alliance 109: McKinney vs. Irizarry is the hundredth-tenth event of Legacy Fighting Alliance and took place on June 5, 2021. It aired on UFC Fight Pass.
 Terrance McKinney, coming off a knockout win at LFA 107, is looking to solidify himself at the top of the lightweight division. He will face top Puerto Rican prospect Michael Irizarry in the main event of LFA 109.
 Legacy Fighting Alliance 110: Johnson vs. Horiuchi is the hundredth-eleventh event of Legacy Fighting Alliance and took place on July 2, 2021. It aired on UFC Fight Pass.
 The main event will feature a LFA Light Heavyweight Championship title fight between top undefeated prospect Joshua Silveira and regional kingpin Jesse "Hollywood" Murray. The co-main event will also feature a title fight when top contenders Charles "Inner G" Johnson and Yuma Horiuchi vie for interim LFA Flyweight Championship. On June 29, Silveira vs. Murray was postponed to a later date and the Flyweight Interim title bout was promoted to the main event.
 Legacy Fighting Alliance 111: De Sa vs. Bonfim is the hundredth-twelfth event of Legacy Fighting Alliance and took place on July 16, 2021. It aired on UFC Fight Pass.
 The event was headlined by a lightweight bout between Rangel De Sa and Ismael Bonfim.
 Legacy Fighting Alliance 112: Welterweight Tournament is the hundredth-thirteenth event of Legacy Fighting Alliance and took place on July 19, 2021. It aired on UFC Fight Pass.
 The event featured a welterweight tournament, held to determine the new LFA champion. Gabriel Bonfim met Brenner Alberth in the first semifinal bout, while Diego Dias met Carlos Leal in the second semifinal bout.
 Legacy Fighting Alliance 113: Lewis vs. Petersen is the hundredth-fourteenth event of Legacy Fighting Alliance and took place on July 30, 2021. It aired on UFC Fight Pass.
 The event was headlined by a heavyweight bout between Thomas Petersen and Vernon Lewis for the vacant LFA Heavyweight Championship.
 Legacy Fighting Alliance 114: Souza vs. Garcia is the hundredth-fifteenth event of Legacy Fighting Alliance and took place on August 27, 2021. It aired on UFC Fight Pass.
 An LFA Featherweight Championship bout for the vacant title between Bruno Souza and Javier Garcia headlined the event.
 Legacy Fighting Alliance 115: Silveira vs. Cummins is the hundredth-fifteenth event of Legacy Fighting Alliance and took place on September 24, 2021. It aired on UFC Fight Pass.
 Legacy Fighting Alliance 116: Fremd vs. Valente is the hundredth-sixteenth event of Legacy Fighting Alliance and took place on October 22, 2021. It aired on UFC Fight Pass.
 The event was headlined by a middleweight bout between Josh Fremd and Renato Valente.
 Legacy Fighting Alliance 117: Dias vs. Tanaka is the hundredth-seventeenth event of Legacy Fighting Alliance and took place on November 5, 2021. It aired on UFC Fight Pass.
 Legacy Fighting Alliance 118: Askar vs. Gomes is the hundredth-eighteenth event of Legacy Fighting Alliance and took place on November 12, 2021. It aired on UFC Fight Pass.
 Legacy Fighting Alliance 119: Silveira vs. Revel was the hundredth-ninenth event of Legacy Fighting Alliance and took place on December 3, 2021. It aired on UFC Fight Pass.
 The event was headlined by a LFA Middleweight Championship bout for the vacant title between Josh Silveira and Jared Revel.
 Legacy Fighting Alliance 120: Cantuária vs. Horth was the hundredth-tenth event of Legacy Fighting Alliance and took place on December 10, 2021. It aired on UFC Fight Pass.
 The event was headlined by a LFA Women's Flyweight Championship bout for the vacant title between Jamey-Lyn Horth Wessels and Mayra Cantuária.