This paper analyses the colloquialization of football-match broadcastings in Peninsular Spanish throughout the 20th century, in line with other recent works dealing with the colloquialization of mass-media. To do so, it accounts for (a) linguistic features, (b) register variation, and (c) external factors related to colloquialization. The analysis is based on a self-compiled database of audio-visual recordings aired between 1968 and the 2000s in Tv and radio. According to results, colloquialization in Peninsular Spanish football broadcasts was developed during three main periods: 1960s–1980s, 1980s–1990s, and 1990s up to now. Specifically, colloquialization can be measured by speech speed, vocabulary and the use of address terms, among other features. These features, in turn, are associated with register variation properties, such as changes in the proximity shared by speakers or the presence of day-to-day topics in broadcastings. Last, some external factors, such as the influence of historical events or the role of announcers also seem to affect the results analysed.