2018–19 Tercera División

The 2018–19 Tercera División was the fourth tier in Spanish football. It began in August 2018 and ended in late June 2019 with the promotion play-off finals.

Competition format

 * The top four eligible teams in each group would play the promotion playoffs.
 * The champion of each group would qualify to 2019–20 Copa del Rey. If the champion is a reserve team, the first non-reserve team qualified would join the Copa.
 * In each group, at least three teams would be relegated to Regional Divisions.

Controversy in Group 8
After being relegated, Real Burgos sued the Castile and León Football Federation arguing that the postponement of their match in the previous season against Arandina forced them to play three games in seven days with few rounds left, harming their performance and finishing the league in relegation positions.

Initially, they were admitted in Tercera División, in application of the precautionary measures by the Judgement, but later the Royal Spanish Football Federation revoked the decision commenting in a statement that the responsibility of organising the competition is theirs and not of the Regional federation.