Three clubs are relegated from La Liga at the end of a standard season. The teams finishing 18th, 19th and 20th drop from Spain’s top division into Segunda División, the country’s second tier.
La Liga uses a 20-club double round-robin format: each team plays 38 matches, once at home and once away against every other club. The bottom three are determined by the final table, with points first and tiebreaking criteria applied when teams finish level.
Promotion works in reverse. The top two Segunda División teams normally rise automatically, while teams finishing third through sixth enter promotion play-offs for the final place. That means three clubs go down but only one of the promoted clubs is decided through a play-off.
A common mix-up is confusing La Liga’s system with leagues that relegate two or four teams. The number can change in exceptional circumstances because of league expansion, financial penalties or competition rules, but three is the standard arrangement for a 20-team season.