The 2020–21 Tercera División was the last for this league as the fourth tier of Spanish football. It began in October 2020 and ended in June 2021 with the second phase and promotion play-off final in the Canarian group. Also, the Tercera División dropped down to the fifth level and Segunda B to the fourth, with Tercera suffixing the federation's Spanish initials RFEF to its name and Segunda B replacing the B with those initials after the creation of a new, two-group, 40-team third division called Primera División RFEF that would begin in 2021–22.