Share of believers of a religion other than Catholicism in Spain Oct 2011-May 2026

Share of believers of a religion other than Catholicism in Spain from Oct 2011 to May 2026

Spain has historically been one of Europe's most deeply Catholic countries, but its religious landscape is now slowly but steadily diversifying. The share of Spaniards who identify as believers of a religion other than Catholicism rose from around 2.4% in October 2011 to about 3.6% by May 2026, according to data from Spain's CIS barometer. While this remains a small minority, the gradual upward trend - alongside a sharp fall in Catholic identification - marks a meaningful shift in one of Europe's traditionally most Catholic nations. For most of the twentieth century, Spain was almost synonymous with Catholicism, the faith deeply intertwined with national identity, politics, and daily life. The slow emergence of other religions, however small in percentage terms, signals the arrival of genuine religious pluralism in a society long defined by a single dominant church. The wider continental picture is in our religion in Europe analysis.

The trend has not been perfectly smooth. The share peaked at 3.3% in June 2018 before dipping back toward 2.4% in 2023, then climbing again to around 3.2-3.6% by 2024-2026. These fluctuations partly reflect the month-to-month nature of CIS survey sampling, but the broad direction is one of slow growth in non-Catholic faiths. Because each monthly barometer surveys a different sample of a few thousand people, a category as small as 3% can easily move up or down by half a percentage point from one survey to the next without any real change in the underlying population. Analysts therefore focus on the multi-year trend rather than individual monthly readings.

This gradual rise is driven largely by immigration, which has brought Protestant, Muslim, and Orthodox communities to Spain. Spain experienced one of Europe's largest immigration waves in the early twenty-first century, with millions of newcomers arriving from Latin America, North Africa, and Eastern Europe, each bringing their own religious traditions to a country that had been religiously homogeneous for centuries. This influx fundamentally reshaped the religious map of a nation that, for most of its modern history, had known little faith diversity beyond its dominant Catholic Church, and it explains why almost all of the growth in non-Catholic belief is concentrated among foreign-born and dual-nationality residents. The global faith context is in our world religions analysis.

It is important to view this small minority against the backdrop of Spain's broader religious transformation. While non-Catholic believers grew modestly, the much larger story is the collapse of Catholic identification (from over 70% in 2011 to around 56% by 2025) and the surge in non-believers and atheists (to nearly 40%). In just fifteen years, Spain has gone from a country where roughly seven in ten people called themselves Catholic to one where barely more than half do, while the non-religious share has risen to rival the Catholic bloc. This is one of the fastest religious transformations recorded in any major European country. The population behind these shifts is covered in our world population analysis.

Non-Catholic Believers in Spain by Year (2011-2026)

The table tracks the share across the full period, showing the gradual rise from 2.4% in 2011, the 3.3% peak in 2018, a dip around 2023, and the recent climb to 3.6% by 2026. The fluctuations reflect both genuine change in the population and the inherent variability of monthly survey data, where small sample shifts can move a figure of this size by several tenths of a percentage point. Read as a whole, however, the table reveals a clear long-term direction: the slow but steady growth of non-Catholic faiths in a country that was, until recently, almost entirely Catholic. This pattern of religious diversification is visible across much of Europe.

The Fifteen-Year Trend in Non-Catholic Believers

The fifteen-year trend line tells a story of gradual, uneven growth. The share climbed steadily through the 2010s to its 3.3% peak in 2018, reflecting growing immigration and religious diversity. It then fell back during the early 2020s - possibly influenced by pandemic-era survey conditions and sampling variation - before recovering to new highs around 3.6% in the mid-2020s. The overall trajectory is clearly upward, even if the path is bumpy. Smoothing out the monthly noise, the share has roughly risen by half over the fifteen-year period - from around 2.4% to 3.6% - which represents a 50% relative increase even though the absolute change is just over one percentage point. For a category measuring religious minorities, that is a substantial proportional shift. Demographic change and migration are the key drivers behind these numbers.

The 2018 Peak and Subsequent Fluctuations

The 3.3% peak in June 2018 stood as the series high for several years. The subsequent dip to 2.4% by September 2023 illustrates the volatility of the monthly barometer data - small sample shifts can move the figure by half a percentage point or more. The recovery to 3.2% in July 2024 and approximately 3.6% by 2026 suggests the underlying trend of religious diversification has resumed and even strengthened. The July 2024 figure was notable at the time as the highest in a five-year period, and subsequent readings pushing toward 3.6% indicate that the dip of the early 2020s was likely a temporary fluctuation rather than a reversal of the long-term trend. Globally, similar patterns of religious diversification are underway.

Which Non-Catholic Religions Do Spaniards Follow?

The CIS barometer does not ask respondents which specific non-Catholic religion they follow, so the 3.6% figure covers all non-Catholic faiths combined into a single category. To understand the composition of that minority, researchers turn to other sources - notably Spain's Observatory of Religious Pluralism, which tracks the individual faith communities in detail. According to its 2018 data, Protestants made up around 2% of the population, Muslims around 1.5%, and Orthodox Christians around 1.1%, with smaller numbers of Buddhists, Hindus, Jews, and followers of other traditions. These figures overlap with, but are measured differently from, the CIS self-identification series, which is why the totals do not line up exactly.

Protestant Christianity, including a significant evangelical community, is the largest non-Catholic faith, partly reflecting Latin American immigration. Evangelical and Pentecostal churches have grown rapidly among immigrants from countries like Colombia, Ecuador, and Brazil, where these denominations are widespread, and Spanish-language evangelical congregations have become a visible feature of many immigrant neighbourhoods. Islam is the second-largest non-Catholic faith, concentrated among immigrants from Morocco and other North African and Middle Eastern countries. Morocco shares deep historical and geographic ties with Spain, and Moroccans form one of the largest immigrant communities in the country, giving Islam a long-established and growing presence, particularly in Catalonia, Andalusia, and the North African enclaves of Ceuta and Melilla.

Orthodox Christianity, the third major non-Catholic faith, has grown with Eastern European immigration, particularly from Romania, which sent large numbers of workers to Spain during its construction boom of the 2000s. Romanians remain one of the largest foreign communities in Spain, and their predominantly Orthodox faith has established a visible Orthodox presence in many Spanish cities, complete with new parishes and churches serving the diaspora. These communities are heavily concentrated among Spain's immigrant and dual-nationality populations, rather than the native-born majority, which is why they add to the wider religious mix found across Europe without changing the overwhelmingly Catholic-or-secular character of Spanish society as a whole.

The Bigger Picture - Spain's Religious Identity in 2026

Putting the 3.6% non-Catholic believers in context: Spain in 2026 is split roughly between a shrinking Catholic majority (around 56%), a large and growing bloc of non-believers, atheists, and agnostics (nearly 40%), and the small minority of other-religion believers (3.6%). The dominant trend is secularisation - the move away from Catholicism toward no religion - rather than conversion to other faiths. This three-way split - a shrinking Catholic bloc, a surging non-religious bloc, and a small but slowly growing minority-faith bloc - captures the essence of Spain's modern religious landscape. Each group has its own demographic profile: Catholics skew older, the non-religious skew younger and native-born, and minority-faith believers skew toward immigrant communities. The economic backdrop to these social shifts connects to our global economy analysis.

The Catholic Decline Behind the Numbers

The rise in non-Catholic believers is best understood alongside the dramatic decline of Catholicism in Spain. In 2011, over 70% of Spaniards identified as Catholic; by 2025, that had fallen to around 56% - a loss of roughly 15 percentage points in just over a decade. Among those who remain Catholic, a large majority are non-practising, rarely attending mass. The CIS data consistently shows that of the roughly 56% who still identify as Catholic, only around 19% describe themselves as practising, while the remainder retain a cultural or nominal Catholic identity without regular religious observance. This gap between identity and practice is itself a marker of advancing secularisation, with many nominal Catholics likely to drift toward no religion over time.

Crucially, most of the Spaniards leaving Catholicism are not converting to other religions - they are becoming non-believers, atheists, or agnostics. This is why the non-believer category has surged to nearly 40% while non-Catholic believers grew only modestly to 3.6%. Spain's religious change is therefore overwhelmingly a story of secularisation rather than religious switching between faiths. The data shows two parallel movements: a large internal shift among native Spaniards from Catholicism to no religion, and a much smaller external addition of non-Catholic believers through immigration. The first dwarfs the second, which is why the headline religious story in Spain is the decline of Catholicism and the rise of the non-religious, not the growth of minority faiths. This secularising trend is seen across much of the European continent.

How Immigration Drives Non-Catholic Belief

The growth in non-Catholic believers is closely tied to immigration. Research on the CIS data shows a striking pattern: among people with solely Spanish nationality, only around 2.2% are believers of another religion, but among those with both Spanish and another nationality, that figure jumps to around 18.7% - almost nine times higher. This shows that religious diversity in Spain is overwhelmingly concentrated among immigrant and dual-nationality communities. The nearly ninefold difference between the two groups is one of the clearest findings in the CIS data, and it underscores that Spain's religious pluralism is fundamentally a product of migration rather than conversion among the native-born population. As Spain has become a destination for migrants from Latin America, North Africa, and Eastern Europe, it has imported the religious diversity those regions carry.

This nationality gap explains both the slow overall growth and the fluctuations in the non-Catholic believer share. As immigration levels change and as immigrant communities establish themselves, the share of other-religion believers shifts. It also explains why the figure remains small overall: the native-born Spanish majority is overwhelmingly either Catholic or non-believing, with very few following other religions. Without continued immigration, the non-Catholic believer share would likely be a fraction of its current level, since conversion to minority faiths among native Spaniards is rare. The 3.6% figure is, in effect, a measure of how much immigration has reshaped Spain's religious composition. Population growth and migration patterns underpin these religious trends.

How the CIS Barometer Measures Religion

The data comes from the Centro de Investigaciones Sociologicas (CIS), Spain's state-run sociological research centre, which conducts monthly barometer surveys of several thousand people across the country. The key question asks respondents: "How do you define yourself in religious matters: Catholic, believer in another religion, non-believer or atheist?" Each respondent chooses a single category, and the "believer in another religion" responses form the basis of this series. Because the CIS is a public, state-funded body with a long and consistent track record, its barometers are widely regarded as the authoritative source on Spanish religious identity, cited by academics, journalists, and statistical compilers alike.

Because the CIS surveys are conducted monthly with varying samples, the figures fluctuate from survey to survey - which is why the non-Catholic believer share has bounced between roughly 2.4% and 3.6% over the period rather than following a perfectly smooth line. From 2019, the CIS began differentiating between practising and non-practising Catholics, but the "other religion" category has remained consistent throughout, allowing the long-term trend to be tracked. This methodological consistency is valuable for researchers, since it means the non-Catholic believer series can be compared reliably across the full 2011-2026 period without breaks or redefinitions that would complicate the analysis.

A key limitation is that the CIS does not ask which specific non-Catholic religion respondents follow, so the category is a single combined figure. For the breakdown by specific faith, researchers rely on other sources like the Observatory of Religious Pluralism. Despite these limitations, the CIS series is by far the most consistent and reliable long-run measure of Spanish religious self-identification available. With monthly surveys stretching back well over a decade and a stable core question, it offers an unusually rich picture of how a major European society's religious identity has evolved. Few countries have comparable monthly religious-identification data over such a long period, making the Spanish series a valuable case study in European secularisation. Such methodological nuances affect religious data collection worldwide.

Religious Diversity Across Spain's Regions

Spain's non-Catholic believers are not evenly spread across the country. Religious diversity is concentrated in the regions and cities that have received the most immigration - particularly Catalonia, Madrid, the Valencian Community, and Andalusia. Barcelona and Madrid, as Spain's largest and most cosmopolitan cities, host the most diverse religious communities, including significant Muslim, Protestant, and Orthodox populations. These metropolitan areas have long been the primary destinations for immigrants, who cluster in particular neighbourhoods where places of worship, community organisations, and support networks for their faiths have developed over the years.

By contrast, Spain's more rural and inland regions remain overwhelmingly Catholic (at least nominally) with very few non-Catholic believers. In the interior provinces of Castile, Extremadura, and rural Aragon, traditional Catholic identity - even if largely non-practising - remains the default, and religious minorities are scarce. These areas have seen far less immigration than the coast and the big cities, preserving a more homogeneous, if increasingly secular, religious profile. This urban-rural divide in religious diversity mirrors patterns seen across Europe, where immigration and the religious pluralism it brings are concentrated in major urban centres. The same dynamic appears in France, Germany, the UK, and Italy, where capital cities and industrial regions host the most religiously diverse populations while rural hinterlands remain more traditionally Christian or secular. The coastal and metropolitan areas that drive Spain's economy are also the centres of its religious change.

This geographic concentration helps explain why the national figure remains modest at 3.6%, even though specific neighbourhoods in Barcelona or Madrid may have much higher shares of non-Catholic believers. As immigration continues and immigrant communities establish themselves across more of the country, this diversity is likely to spread gradually beyond the major urban centres. Smaller cities and towns that have begun receiving migrant workers in agriculture, services, and construction are slowly seeing the emergence of mosques, evangelical churches, and Orthodox parishes that would have been unthinkable a generation ago. The geography of Spanish religious diversity is, in this sense, a map of the country's immigration patterns. The broader social and digital trends shaping these communities are explored in our social media statistics analysis.

The Future of Religious Diversity in Spain

Looking ahead, the share of non-Catholic believers in Spain is likely to continue its slow upward trend, barring major changes in immigration policy or migration patterns. The key driver - immigration bringing Protestant, Muslim, and Orthodox communities into the country - shows no sign of reversing, and the established communities continue to grow through both new arrivals and natural increase. Second-generation immigrants often retain their families' religious identities even as they integrate into Spanish society, learning the language and entering the workforce, which suggests these faith communities will persist rather than fade. As a result, the non-Catholic share is more likely to drift gradually higher than to fall back toward its earlier levels.

However, the non-Catholic believer share is likely to remain a relatively small minority for the foreseeable future, probably staying in the 3-5% range rather than growing dramatically. This is because the dominant religious trend in Spain - as across most of Western Europe - is secularisation, not religious switching. The native-born Spanish majority continues to move from Catholicism toward no religion at all, rather than toward other faiths. A similar dynamic of a declining national church amid rising secularism can be seen in our population of Finland by religious community analysis.

For Spain, the long-term religious picture is one of a country moving from near-universal nominal Catholicism toward a more secular, somewhat more diverse society. The non-Catholic believers - though small in number - represent the growing religious pluralism of a nation that was, for most of its history, defined by its Catholic identity. Spain's journey from a country where Catholicism was effectively the state religion under Franco, to a constitutionally secular state with growing religious diversity, has unfolded in just a few generations. The 3.6% who follow other faiths are a visible sign of how far that transformation has come. This transformation, while less dramatic than the secularisation trend, is a meaningful marker of modern Spain's evolving character.

Non-Catholic Believers in Spain - Key Statistics

Frequently Asked Questions - Non-Catholic Believers in Spain