Wikipedia - Segunda Federación

Segunda Federación, previously called Segunda RFEF, also officially known as Segunda B, is the fourth tier of the Spanish football league system containing 90 teams divided into five groups. It is administered by the Royal Spanish Football Federation. It is the second tier outside the top two professional leagues, the Primera División (also known as La Liga) and Segunda División (also known as La Liga 2), being behind Primera Federación and above Tercera Federación. The division also includes the reserve teams of a number of La Liga and La Liga 2 teams.

History

On 6 May 2020, the RFEF announced the creation of a new, two-group, 40-team third division called Primera División RFEF, which resulted in the former third division, Segunda División B, dropping down a level and becoming Segunda División RFEF; the changes were made effective for the 2021–22 campaign.

In July 2022, the division was renamed Segunda Federación.