On September 7, 2018, Tawanchai defeated Muay Thai Fighter of the Year 2017 Kulabdam Sor Jor Piekuthai.
On July 27, 2019, Tawanchai fought for the first time under kickboxing rules for the Wu Lin Feng World Cup in China, it was his first fight outside of Thailand and he won by decision.
[citation needed] He then fought Sitthichai Sitsongpeenong at ONE Championship: Battleground 3 under Muay Thai rules.
[12] Tawanchai faced Petchmorakot Petchyindee Academy for the ONE Featherweight Muay Thai World Championship at ONE 161 on September 29, 2022.
[18] Tawanchai was scheduled to defense the title against Superbon Singha Mawynn on October 7, 2023, at ONE Fight Night 15.
[22] The match between Tawanchai and Superbon for the ONE Featherweight Muay Thai World Championship was rescheduled on December 9, 2023, at ONE Fight Night 17.
[27] For his fourth title defense, Tawanchai was scheduled to face Jo Nattawut in a trilogy on November 8, 2024, at ONE 169.
[28] However, the bout was removed from the event due to Nattawut injury after losing via knockout against Superbon Singha Mawynn at ONE Friday Fights 81.
[29] The rematch between Tawanchai and Superbon for the ONE Featherweight Muay Thai World Championship took place on January 24, 2025, at ONE 170.