Spain has no official religion. The Spanish Constitution of 1978 abolished the Roman Catholic Church as the official state religion, while recognizing the role it plays in Spanish society.
As of 2018, 68.5% of the population define themselves as Catholic, 26.4% as non-believers or atheists, and 2.6% other religions.
Catholic Christianity is the largest religion in Spain. Only 3% of Spaniards consider religion as one of their three most important values, even lower than the 5% European average.
In a recent study it was found that 68.9% of Spaniards self-identify as Catholics, (46.4% define themselves as not practising, while 22.5% as practising), 2.9% as followers of other faiths (including Islam, Protestant Christianity, Buddhism etc.), and 27.7% identify as atheists (11.0%), agnostics (8.4%) or non-believers (8.3%) as of May 2019. Most Spaniards do not participate regularly in religious worship. This same study shows that of the Spaniards who identify themselves as religious, 27.2% never attend mass, 28.2% barely ever attend mass, 17.0% attend mass a few times a year, 7.6% two or three times per month, 11.6% every Sunday holidays, and 2.1% multiple times per week.