It's also the time when they may need access to capital to launch start-ups or to go into business.
The Student Loan Scheme Annual Report cites 12-year-old Australian data to claim that there is no impact from debt on housing and child-bearing.
This ignores a decade of stagnant real wage growth, house prices that have more than doubled over that period, and a near doubling of debt as fee rises have outstripped inflation and eligibility for allowances has been steadily reduced.
It also ignores the differences across the Tasman where loan repayments start at 4 per cent of income over $55,000.
NZUSA's most recent survey (2014, of 5000-plus students) revealed that three in four students expected their debt would impact on their ability to save for their retirement; 7 in 10 on their ability to buy a house; two-thirds were put off going on to higher study; and more than a third said it would affect their choices about having children.
The long-term implications of this are significant.
United States studies, where the debt levels on graduation are actually similar to here - and where wages are higher - show that a household with student debt is $300,000 worse off in retirement than one without, mostly because of the delay in getting into the housing market.
This is eerily similar to the $300,000-$450,000 that the Financial Services Council says people will need in their KiwiSaver account to guarantee a comfortable requirement.
It also puts into context the Universities NZ calculation that people with degrees on average gain around $500,000 more over their lifetime than those who leave school and don't go into tertiary study.
We all know that life is increasingly more complicated, this is true also of the world of work. The need for training and retraining is an essential feature of almost all future jobs. Not least the ones that haven't even been dreamed up yet.
In the same way that primary education became free in 1877, and secondary schooling free in 1944, in the 21st century, tertiary education needs to be free and for everyone too.
It's worth remembering that in 1939, only 25 per cent of 12- to 18-year-olds went to secondary school, itself a massive increase from the 3 per cent in 1901 when it was for the wealthy elite.
One hundred years on, we live in a different world. Labour's recent recommitment to fee-free education, joining NZ First, the Greens and United Future, isn't about supporting the elite.
Given the entry requirements into high-financial-return courses, and the high correlation between secondary school success and wealth that already exists, those roles are highly restricted. Most are already supported by scholarships and/or fee subsidies.
Fee-free education policies are about extending free education to the rest, and in particular the 300,000 students who are not at university.
The graduate earning study showed that plenty of jobs that our society relies upon don't currently make financial sense: nursing, teacher aides, social workers, creative arts. But we still need people qualified to do them, and would be poorer without them.
It also showed that around two thirds of a graduate's increased lifetime earnings is chewed up in course costs, loan repayments and foregone earnings while studying.
It's not naive to say that education is a good thing, and it needs to be available for everyone, not just those for whom an investment of hundreds of thousands of dollars - including their time - is possible.
Fee-free education will give opportunities to older New Zealanders who wish to retrain, and support businesses who want to put their workers through programmes that will increase their productivity.
Combined with articulation agreements between regional polytechnics and institutions of higher learning, increased participation would be a saviour for struggling institutes of technology and polytechs, and provide better prepared and less indebted university students.
We've seen major coverage about the government "getting tough" on student debtors this year. It's time that we got tough on the causes of debt: fees and students being forced to borrow to live. Tomorrow, March 2, $15 billion debt day, is where this starts.
Dr Alistair Shaw is the executive director of the New Zealand Union of Students' Associations.