Among people in their 20s and early 30s, the proportion who are married has dropped dramatically — for example, only about 20% of women aged 25–29 were married in recent surveys, compared to over 35% two decades ago.
De facto (live-in partner) relationships have risen correspondingly, now common for many couples, especially those with kids.
Your children's and nieces/nephews' generation (likely millennials and Gen Z -- "Zoomers") often see little practical need for formal marriage, especially since Australian family law treats long-term de facto couples almost the same as married ones for property, superannuation, spousal maintenance, and children.
The "shut up, dad!" response is pretty classic — it's a mix of independence, eye-rolling at "old-school" ideas, and perhaps not wanting to explain deeper reasons.
Here are the main factors driving this shift, based on research and reports:
Marriage has become optional and more "deliberate"
People now view it as a conscious choice rather than a default life step. Many couples "try before you buy" by living together first (83% of couples who do marry have cohabited beforehand, up hugely from decades ago). If the relationship works long-term without the certificate, why add the formality? Stigma around living together or having kids outside marriage has largely vanished.
Financial and economic pressures
Housing affordability, high cost of living, student debt, and career instability make big life commitments feel risky. Weddings themselves are expensive (even modest ones), and many young people delay or skip marriage until (or unless) they feel financially secure. Economic insecurity also contributes to fewer people forming partnerships at all, or keeping them informal.
Later life milestones
People spend longer in education, take time to build careers (especially women, with greater workforce participation), and travel or focus on personal growth. The median age for first marriage has risen steadily (now around 30+ for both men and women). By the time they're "ready," marriage might not feel urgent — especially if kids arrive via de facto relationships.
Changing attitudes and fear of divorce
Many in this age group grew up seeing high divorce rates among their parents' generation (boomers had the peak). That creates caution: "Why risk the legal/financial mess if de facto offers similar protections?" Marriage is sometimes seen as outdated, unnecessary for commitment, or even a potential trap if things go wrong. There's also more acceptance of diverse relationship styles — single life, serial monogamy, or long-term partnering without rings.
Cultural and social shifts
Less religious influence (fewer church weddings), dating apps changing how relationships form, and a broader cultural glamorisation of independence and self-fulfilment all play roles. For some, marriage feels like conforming to expectations they don't share.
In short, it's not that your kids and their generation don't value committed relationships — many are in them, having children, building lives together — they just don't see the legal/ceremonial step as adding much value in modern Australia.
The practical rights are largely covered without it, and the costs (financial, emotional, social) can feel high for something that's no longer seen as essential.If you're curious, a gentle, non-judgmental chat about their specific views (maybe over a beer rather than "why not marry?") might reveal more personal reasons — like "we're happy as is" or "the wedding industry is ridiculous." But yeah, the era when marriage was the automatic next step after a relationship has passed for many. It's a big social change, but families still thrive in de facto setups just fine.
ME: You don't see any connection between low marriage rates and plunging birth rates in nearly all thew world?
Yes, there is a clear and well-documented connection between declining marriage rates (or more broadly, declining rates of stable partnerships) and plunging birth rates across much of the world, including Australia. This link shows up consistently in demographic research, and it's often described as one of the strongest proximate (direct, immediate) causes of falling fertility in recent decades.
The Global Picture
Fertility rates (measured as total fertility rate, or TFR — average children per woman) have fallen dramatically worldwide since the mid-20th century, now below replacement level (2.1) in most developed countries and dropping fast in many developing ones too. Recent analyses (up to 2025 data) attribute a large portion of this decline to fewer people entering committed relationships that lead to children.
In many societies, married people have significantly higher fertility than unmarried or even cohabiting ones. Studies from the Institute for Family Studies and others show married couples are far more likely to have children (and more of them) than singles or cohabiters.
Declining marriage rates explain a substantial share of fertility drops — for example, one analysis found ~75% of the U.S. fertility decline since 2007 tied to shifts in who is married. Similar patterns appear in cross-country data, where drops in people being married or in stable couples track almost one-to-one with fewer births.
In places like East Asia (e.g., South Korea, where extramarital births are rare), falling marriage rates account for the majority (80%+) of birth rate declines over recent decades. In Western countries, where cohabitation is more common, the story includes both fewer partnerships overall and sometimes lower fertility even within cohabiting unions due to greater instability.
Other factors contribute (economic pressures, education/career priorities, housing costs, shifting norms around family), but relationship formation — especially marriage as a stable context for kids — is frequently the biggest single driver in decomposition studies.
In Australia SpecificallyAustralia mirrors this trend closely. The TFR has continued falling, hitting around 1.48 in 2024 and projected to drop further to ~1.42 in 2025–26 (well below replacement). Marriage rates have declined steadily, with fewer people marrying young or at all, while cohabitation has risen but not fully offset the drop in partnered people (especially at peak childbearing ages).
From 1991–2019 (and trends continuing), the falling proportion of partnered women (particularly married) contributed negatively to fertility, especially among younger ages. Births to married mothers dropped from ~77% to ~64%, with cohabiting births rising but not enough to compensate fully.
Increasing singlehood (neither married nor cohabiting) among women in childbearing years has directly pulled down overall fertility levels.
Even though Australian law treats long-term de facto partners similarly to married ones for many rights, cohabiting couples often have fewer children on average than married ones (due to less perceived stability or commitment), and many people delay or skip partnering altogether.
Your observation about your kids and nieces/nephews fits right in: they're in relationships (often de facto), having or planning kids, but skipping formal marriage.
In aggregate, though, fewer people reach that stable partnered stage (or do so later), fewer have multiple kids, and overall births drop. It's not that committed relationships have vanished entirely — many still form families — but the shift away from marriage (and sometimes away from any long-term partnership) means fewer births than in past generations.
In short, yes — the connection is strong and causal in many analyses: fewer marriages/partnerships → fewer babies. It's a key part of why global birth rates are plunging, even as other explanations (like costs or individualism) play supporting roles. If policymakers want to boost fertility, addressing barriers to stable relationships often comes up as more impactful than just cash incentives for kids.
