When Adult Children Move Home: A Financial Plan for Both Generations

Agree on a board amount, set a savings target, and tie the move-out date to a financial milestone rather than a calendar date. An adult child moving home can work well for both generations when the arrangement has that kind of structure, clear boundaries, and an end point everyone can see. The households where we see this succeed treat it as a defined financial project, not an open-ended favour.

More than a third of New Zealand families with children now have an adult child aged 18 or older living at home, according to 2023 Census data from Stats NZ. Housing costs are the primary driver, and the trend is not going away soon. Internationally, the pattern is similar: a majority of Americans aged 18 to 24 were living with parents as of 2022, per Pew Research Center analysis, and the Australian Bureau of Statistics reports a comparable upward trend. Hayden Mullholland, one of the Become Wealth financial advice team, sees a consistent pattern across the families he advises:

"The arrangements that work usually have a specific number attached to them, usually a deposit target or a student loan balance. Once both sides can see the same number and track it together, the whole dynamic changes. Without that, what starts as six months quietly becomes two years."

Set the Financial Framework First

The most productive conversation a family can have before an adult child moves back is about money. Three things to agree on early:

1. A board amount. A range of $150 to $250 per week is what we might often see with client families, depending on what it covers (meals, power, internet, laundry). This sits below flatting costs in most cities, and the gap creates room to save. For adult children between jobs, non-financial contributions such as cooking, chores, and property maintenance can substitute until income stabilises.
2. A savings and debt repayment target. Agree on what the adult child will do with the money they save by living at home. Paying down a student loan faster, building a first-home deposit, or even increasing KiwiSaver Scheme contributions are all concrete goals worth locking in.
3. A move-out milestone tied to a financial target. A calendar date alone creates pressure without direction. Tying the timeline to a measurable goal ("once you have saved $30,000 toward a deposit" or "once your student loan is below $10,000") gives both sides a shared benchmark and a reason to track progress together.

If the adult child is between jobs or underemployed, that period at home is also an opportunity to pursue better-paying work, pick up additional skills, or build income from a side project. The financial framework works best when income is growing alongside the savings habit.

One practical point: if the adult child is receiving a government benefit such as Jobseeker Support or the Accommodation Supplement, the board arrangement and living situation can affect their entitlements. Check with Work and Income before finalising amounts.

Board payments received from a family member in your own home are generally treated by Inland Revenue as a domestic arrangement, not rental income. The Residential Tenancies Act 1986 also generally excludes family boarders where you share kitchen, bathroom, or laundry facilities. The FAQ section below covers both points in more detail.

A Worked Example: The 18-Month Deposit Sprint

Consider an adult child earning $55,000 per year gross, with $8,000 in their KiwiSaver Scheme balance after four years of contributions, and an $18,000 student loan. Here is how the weekly pay breaks down. Gross weekly pay is approximately $1,058. After PAYE of roughly $200 (including the ACC earner's levy, based on current income tax rates), a 3.5% KiwiSaver Scheme employee contribution of approximately $37, and mandatory student loan repayments of roughly $71 per week (12% on income above the $24,128 repayment threshold, per Inland Revenue), take-home pay lands at approximately $750 per week.

A realistic weekly budget while living at home:

• Board: $150
• Transport, phone, personal spending: $200
• Voluntary KiwiSaver Scheme top-up: $40
• Savings: $360

That accounts for $750. Over 18 months (78 weeks), bank savings total roughly $28,100.

The KiwiSaver Scheme balance after 18 months combines the existing $8,000, roughly $5,300 in employee and employer contributions over 18 months (3.5% each on $55,000, with the employer's share reduced by employer superannuation contribution tax), and approximately $3,120 in voluntary top-ups ($40 per week for 78 weeks). That brings the balance to approximately $16,400 before investment returns and after fees. Of that, roughly $15,400 is available through the KiwiSaver first home withdrawal, since at least $1,000 must remain in the account.

Adding those up: bank savings of approximately $28,100 and a KiwiSaver Scheme withdrawal of approximately $15,400, for a total toward a deposit of approximately $43,500.

On a $650,000 regional property requiring a 10% deposit of $65,000, that leaves a gap of around $21,500. Some parents close this gap by quietly saving the board payments they receive and gifting the total back at move-out. This is a version of the bank of mum and dad with built-in structure. There is no gift duty in New Zealand (abolished in 2011), and since the board was a domestic arrangement, no tax complexity arises. Board savings of $150 per week over 18 months total approximately $11,700, which would bring the deposit to roughly $55,200. The remaining gap of around $9,800 is several months of additional saving, or a conversation with the lender about whether the deposit plus strong savings history qualifies for a slightly lower deposit ratio.

These figures are illustrative. Individual tax positions, benefit entitlements, and KiwiSaver Scheme balances will shift the numbers. Mapping out how the pieces fit together for your situation is where working with a first-home adviser adds the most value.

Negotiate Boundaries and Expectations

For Parents: It Is Your House

Have the conversation about what is and is not acceptable before the move-in, covering:

• Shared and private spaces
• Laundry, meals, and groceries
• Power, water, and internet access
• Privacy, for both generations
• Visitors, including overnight visitors and partners
• Chores and household maintenance
• Noise, smoking, drinking
• What changes if the adult child enters or leaves a relationship during the arrangement

Playing things by ear is the fastest path to resentment. A written household agreement, even informal and on a single page, makes expectations visible and reduces the chance of selective memory on either side.

Let your child choose their own chores where possible. Ownership improves follow-through.

For Adult Children: It Is Their House

Be upfront about your expectations, your routines, and how you plan to contribute. A few things worth doing before you are asked:

• Propose a board amount based on your income and what seems fair, rather than waiting for your parents to name a figure
• Set up an automatic transfer to a savings account on payday, so the savings target is not left to willpower
• Volunteer for specific recurring chores: cooking two dinners a week, mowing the lawn, handling a household task your parents dislike
• Raise potential friction points early (loud music, late nights, a partner staying over regularly) and propose a solution rather than waiting to be confronted

Common triggers for tension include different standards of tidiness, use of shared living spaces in the evenings, and grocery assumptions: who buys what, and whether the fridge is communal.

It is also worth acknowledging that moving home can feel like a step backwards. It usually is not. Directed saving at this stage of life has a compounding effect that is difficult to replicate later, especially for a first-home deposit. You are making a practical financial decision, and treating it that way makes the arrangement easier for everyone.

Treat Each Other as Adults

A useful test: if either party would find the behaviour patronising or inconsiderate in a flatting situation, it probably does not belong here either.

Adult children moving home will usually be accustomed to considerably more freedom than when they lived at home as teenagers. Compulsory family dinners, curfews, and daily check-ins on their whereabouts are unlikely to be helpful unless they genuinely affect the rest of the household.

The dynamic can slip backwards without either side noticing. Parents may unconsciously revert to a supervisory role; adult children may drift back into expecting meals on the table. Both sides should watch for costs drifting from the agreement: parents absorbing more expenses than planned, or adult children spending freely because their fixed costs are low.

Establish a Timeline With Regular Check-Ins

Six to eighteen months is a realistic window for most arrangements. That is long enough to make meaningful financial progress and short enough to maintain motivation. Monthly or quarterly check-ins give both sides a chance to review how the financial milestones are tracking, whether the arrangement is still working, and what adjustments are needed.

A few warning signs the arrangement may have become unproductive: the adult child stops contributing board or reduces savings without explanation, employment activity has stalled, the original goals have drifted, or the household tension has become routine rather than occasional. These are signals to revisit the agreement, and have a direct conversation about what comes next.

Protect the Parents' Financial Position

Supporting an adult child is a natural instinct. Subsidising them at the expense of your own retirement savings is a different proposition. The costs can accumulate quietly: higher grocery and utility bills, deferred maintenance spending, or lower KiwiSaver Scheme contributions. Insurance is worth checking too. Home contents policies and vehicle insurance may need to be updated to reflect an additional adult resident, and premiums can increase. Notify your insurer so you are not caught out on a claim.

If the arrangement extends beyond the initial timeline, both generations should have clear visibility of each other's financial position. Parents nearing retirement have less time to recover from reduced savings, and the maths can shift quickly. For parents concerned about the longer-term picture, the financial risks of extended support deserve serious attention. A retirement planning review can help clarify whether the current arrangement is sustainable or whether adjustments are needed now.

Look After Everyone's Wellbeing

There can be a stigma attached to adults living with their parents: assumptions of laziness, entitlement, or failure to launch. Given the numbers, those assumptions are increasingly detached from reality. Most young adults returning home are responding to genuine economic pressures.

The arrangement can still weigh on self-worth. Adult children may feel guilty about accepting help. Parents may feel anxious about their child's future or resentful about their own compromised space. Both reactions are common, and neither is a sign of failure.

Watch for persistent changes: withdrawal from social life, increased irritability, disrupted sleep, or loss of interest in activities that previously mattered. Small structural habits help: regular exercise, social contact outside the home, a consistent daily routine, and continued engagement with work or study.

Making It Count

Grown children moving home can genuinely benefit both generations. Young adults often relate to their parents differently as adults, and parents get to know the person their child has become. The arrangement creates time and financial breathing room that few other situations offer.

It works when it has transparency, defined goals, and an end point everyone can see. If you are unsure whether the arrangement is affecting your retirement timeline, or you want to model the deposit path for your child, a conversation with our team can work through the numbers for your specific situation.

Frequently Asked Questions

How much board should I charge my adult child in New Zealand?

There is no fixed rule, but $100 to $200 per week is a common range, calibrated to what the board covers and the adult child's income. The goal is to build their habit of meeting regular financial commitments while leaving enough room for meaningful saving. Two families in identical houses will reasonably arrive at different numbers depending on circumstances.

Does charging board make me a landlord under the Residential Tenancies Act?

Generally, no. The Residential Tenancies Act 1986 excludes boarders who share facilities with the homeowner, that is, where you share kitchen, bathroom, or laundry. A granny flat with its own facilities may not qualify for this exclusion. Board payments from a family member in your own home are also generally treated by Inland Revenue as a domestic arrangement, not taxable rental income. A written household agreement is still useful for clarity, but it does not need to be a formal tenancy agreement.

Can my adult child still receive government support while living at home?

Potentially. Benefits such as Jobseeker Support and Accommodation Supplement are assessed by Work and Income on individual circumstances, and living with parents does not automatically disqualify someone. However, the Accommodation Supplement may be reduced or unavailable depending on income and whether board is being paid. It is worth checking entitlements directly before assuming they disappear.

Should I tell my adult child about my own retirement savings position?

Financial transparency in both directions tends to produce better outcomes. Adult children who understand their parents are making a real financial trade-off are more likely to treat the arrangement seriously and stick to agreed milestones. The conversation does not need to include every detail, but hiding the cost entirely removes an important motivator.