The demographics of the Republic of Ireland are characterized by a growing and gradually ageing population, with population growth driven by both natural increase and sustained net immigration, the latter becoming increasingly significant in recent decades. As of the 2022 Irish census, the population of the state stood at 5,149,139. More recent estimates from 2025 by the Central Statistics Office indicate the population has continued to expand to over 5.4 million. As of 2025, Eurostat data indicates that approximately 23.3% of the state's resident population is foreign-born.

The country enjoys a high life expectancy of approximately 82.4 years (84.5 for women and 80.4 for men). Fertility rates have fallen to approximately 1.49 children per woman, which is below the replacement level of 2.1, and the national birth rate has declined to roughly 9.9 births per 1,000 population. The population is gradually ageing, with the proportion of older age groups increasing.

Over the last three decades, the Republic of Ireland has transitioned from a largely homogeneous society to a more diverse one. This change has been driven primarily by high levels of sustained immigration from both within and outside the European Union. According to 2022 census data, individuals identifying as White Irish constitute approximately 76.6% of the population, a decline from 87.4% in 2006, followed by Other White backgrounds (10.8%), Asian (3.3%), and Black (1.5%). Population density is relatively low at 73 per km2, but remains unevenly distributed, with a high concentration in the capital city of Dublin and its commuter belt and lower densities in many western and rural counties, reflecting longstanding internal migration from peripheral regions to urban centres.

In terms of religious affiliation, Christianity remains the dominant faith, with Roman Catholicism being the largest single denomination at 69.1%. However, religious observance and self-identification have declined in recent years, alongside a significant rise in those reporting "no religion," who now account for 15.4% of the population. English is the dominant language of daily use, with Irish holding constitutional status as the national and first official language and used as a community language in designated Gaeltacht areas.

History

The island of Ireland's population has fluctuated over history. In the 18th and early 19th centuries, Ireland experienced a major population boom as a result of the Agricultural and Industrial Revolutions. In the 50-year period 1790–1840, the population of the island doubled from 4 million to 8 million. At its peak, Ireland's population density was similar to that of England and continental Europe.

This changed dramatically with the Great Famine of the mid-19th century, which led to mass starvation and consequent mass emigration. In the area covering the present day Republic of Ireland, the population reached about 6.5 million in the mid-1840s. Ten years later it was down to 5 million. The population continued a slow decline well into the 20th century, with the Republic recording a low of 2.8 million in the 1961 census.Census.ie – Population of Ireland 1841 – 2006

During the 1960s, the population started to grow once more, although slowly as emigration was still common. In the 1990s the country entered a period of rapid economic growth as a result of the Celtic Tiger Irish economic boom, and the Republic started to receive immigration. Many former Irish emigrants returned home, and Ireland became an attractive destination for immigrants, from other member states in the EU such as Central Europe, but also from outside the EU such as Africa, Asia and elsewhere. With the 2008 onset of the Irish economic and banking crisis, the state's economy suffered, and Ireland has once again been experiencing net emigration of its citizens, but immigration remains high.

In November 2013, Eurostat reported that the Republic had the largest net emigration rate of any member state, at 7.6 emigrants per 1,000 population. However, it had the youngest population of any European Union member state and its population size is predicted to grow for many decades, in contrast with the declining population predicted for most European countries. A report published in 2008 predicted that the population would reach 6.7 million by 2060. The Republic was at the time (mid to late 2000s) experiencing a baby boom, with increasing birth rates and overall fertility rates.Irish Examiner – Baby boom as Irish births reach highest level since 1982 Despite this, the total fertility rate is still below replacement.

Population size Chart

Vital statistics

Life expectancy

In 2023, Our World In Data, estimated the average life expectancy in the Republic of Ireland to be 82.4 years (84.5 for females and 80.4 for males). In 2024, Eurostat estimated it to be 83.1 years, and placed it 9th in Europe. The same year, World Bank's Open Knowledge Repository estimated it to be 83.0 years, placing it 23rd in the world.

Table