The number of families in Census 2022 was 59% higher than in 1996, but the average number of children per family fell by 26%, CSO data shows.
The number of families with no children saw an increase of 11% since 2016, and of 14% compared with 2011.
There were 20% more one-parent father families with children who were renting accommodation than in Census 2016.
The number of same-sex couples increased by 157% compared with 2011 and stood at 10,393 in Census 2022.
Since 2016, the number of cohabiting couples without children living in private households went up by 17%, more than twice the growth rate of married couples without children living in private households.
In Census 2022, 8% of all people in private households lived alone, including 44% of those aged 85 years and over.
Of the 522,486 adults living with their parents, over half were in employment with 54% of males and 50% of females being at work.
There were 50% more adult unpaid carers living with their parents in 2022 than in 2016.
Of the 331,783 children aged under 15 who were in childcare, 3% or 9,789 reported experiencing at least one long-lasting condition or difficulty to a great extent or a lot.