In short

Commercial reverse mortgage rates in Australia now sit around 8.35-9.3%, meaning a $100,000 borrow compounds to roughly $511,000 after 20 years and $769,000 after 25. The government's Home Equity Access Scheme, at a fixed 3.95%, costs about $294,000 less over 20 years on the same borrow. For eligible pensioners, HEAS should be the default before considering a commercial reverse mortgage.

For Australian retirees with substantial home equity but limited liquid retirement savings, the reverse mortgage offers a specific solution: borrow against the home, use the funds for retirement income or major expenses, and let the interest accrue rather than making regular repayments. The loan is repaid when the home is eventually sold — typically on the borrower's death or move to aged care.

The product solves a real and recurring problem. For a 70-year-old with a $1.5 million home, $80,000 in liquid super, and a need for $30,000 to cover medical expenses, the alternatives are limited: sell the home and incur substantial friction costs, ask family for support, or borrow against the home equity. The reverse mortgage provides the third option, with the cost (interest) deferred to the eventual sale.

The trouble is that the cost is not as small as the absence of repayments suggests. The compounding mathematics over a 20-year retirement horizon transforms modest borrows into substantial debts.

What does the compounding curve look like?

The compounding curve. Reverse mortgage interest typically compounds annually (sometimes monthly), with current Australian commercial rates in the 8.35–9.3% range. The basic formula:

Balance after n years = Initial loan × (1 + interest rate)^n

At 8.5% annual compounding (a representative current commercial rate):

  • $100,000 borrowed → $150,366 after 5 years
  • $100,000 borrowed → $226,098 after 10 years
  • $100,000 borrowed → $339,974 after 15 years
  • $100,000 borrowed → $511,205 after 20 years
  • $100,000 borrowed → $768,676 after 25 years

At 8%, the 20-year figure is $466,000. At 9.5%, it is $614,000. The higher the rate and longer the horizon, the more punishing the compounding.

How sensitive is the debt to the interest rate?

The rate sensitivity. Reverse mortgage rates are typically variable, tied to a benchmark plus a margin. A 1% change in the average rate over 20 years adds approximately $103,000 to the eventual debt on a $100,000 borrow. Over a 25-year horizon, the rate sensitivity is even sharper. Borrowers who lock in at a "reasonable" rate find themselves in a much less reasonable position when rates rise — and rate cuts often aren't passed through to existing reverse mortgage borrowers as quickly as they are passed through on standard mortgages.

How much home equity does the loan erode?

The home equity erosion. The strategic question is how much of the home's eventual value is consumed by the loan. Consider a 65-year-old borrowing $100,000 against an $800,000 home at 8.5%, with home value appreciating at 4% annually:

  • Year 0: home $800,000; loan $100,000; equity $700,000.
  • Year 10: home $1,184,000; loan $226,000; equity $958,000.
  • Year 20: home $1,753,000; loan $511,000; equity $1,242,000.
  • Year 25: home $2,133,000; loan $769,000; equity $1,364,000.

For modest borrows over 20+ years, the home appreciates faster than the loan grows. The family's eventual residual is meaningful. The strategy "works" in the sense that home value preserves intergenerational wealth even with the reverse mortgage drawing on it.

But for larger borrows, the picture darkens — and darkens sooner at current rates than it once did. A $400,000 borrow on the same home at 8.5%:

  • Year 0: home $800,000; loan $400,000; equity $400,000.
  • Year 15: home $1,441,000; loan $1,360,000; equity $81,000.
  • Year 17: loan value overtakes home value — the crossover point, roughly a decade earlier than it would have been at the older 7% rates this article previously used.
  • Year 20: home $1,753,000; loan $2,045,000; equity (negative — guarantee applies, equity is zero at sale).

The negative equity guarantee — mandated under Australian regulation — protects the borrower and family from owing more than the home's value at sale. But it doesn't protect the equity itself. For substantial borrows on long horizons, the home value can be entirely consumed — and at today's higher commercial rates, that consumption arrives faster than it would have a few years ago.

What is the Home Equity Access Scheme alternative?

The Home Equity Access Scheme: the government alternative. The Australian government's reverse mortgage product, the Home Equity Access Scheme (HEAS, formerly the Pension Loans Scheme), is materially cheaper than commercial reverse mortgages.

HEAS features include:

  • Lower interest rate — 3.95% per annum (unchanged since January 2022), well below commercial rates.
  • Available to age pensioners and self-funded retirees of Age Pension age.
  • Loan capped based on age and home value, with various structuring options.
  • Loan repaid on sale or death like a commercial reverse mortgage.

At 3.95% compounding:

  • $100,000 borrowed → $147,314 after 10 years
  • $100,000 borrowed → $217,015 after 20 years
  • $100,000 borrowed → $263,398 after 25 years

The difference at 20 years between 3.95% (HEAS) and 8.5% (a representative current commercial rate) is approximately $294,000 on a $100,000 borrow. Over 25 years, the difference is approximately $505,000 — a materially wider gap than when commercial rates sat closer to 7%.

For pensioners eligible for HEAS, the comparison is decisive. HEAS should be the default option; commercial reverse mortgage products should be considered only where HEAS doesn't meet the borrower's specific need (e.g., higher loan amount, faster access).

When do reverse mortgages make sense?

When reverse mortgages make sense. Despite the compounding cost, reverse mortgages can be appropriate in specific scenarios:

Asset-rich, cash-poor retirees. A retiree with a $1.5 million home and limited liquid retirement savings may need to access home equity. The alternatives — selling and downsizing (with substantial friction costs) or extreme spending restraint — may be worse.

Short-term needs. A 75-year-old needing $50,000 for medical equipment or home modifications has a relatively short compounding period (5–10 years to likely aged care entry or death). The cost is manageable.

Top-up income, drawn periodically. A retiree drawing a small pension and needing $500/month additional income for 10 years can borrow incrementally, with the compounding limited to each periodic borrow rather than to a large lump sum.

Reverse mortgages are less appropriate for:

  • Long-horizon borrowers. A 65-year-old with 25+ years of expected retirement faces the worst of the compounding curve.
  • Borrowers with strong family wealth transfer goals. The compounding debt erodes the home equity that would otherwise pass to heirs.
  • Borrowers eligible for HEAS. The government scheme is materially cheaper.

What are the common misconceptions?

Common misconceptions. Several patterns recur:

  • "I'll only borrow what I need." The compounding interest grows the loan even without further borrowing. The "small borrow" can become a large debt over time.
  • "The home will appreciate faster than the debt." True for modest borrows; false for substantial borrows or high-rate periods.
  • "The negative equity guarantee protects the family." It protects from owing more than the home value — but doesn't protect home equity from being substantially consumed.
  • "Reverse mortgage interest is tax-deductible." Generally not, for personal residence borrows. Only deductible if the borrowed funds are used for income-producing purposes — rarely the case in retirement context.

What does the strategic conversation involve?

The strategic conversation. For retirees considering a reverse mortgage:

  • Project the compounding curve at multiple rate scenarios over the borrower's likely horizon. Show the eventual debt at age 80, 85, 90.
  • Compare with HEAS. For pensioners, the comparison is decisive.
  • Consider alternatives. Downsizing, spending restraint, family financial support, government concessions.
  • Plan the repayment trigger. When does the loan end? Aged care entry (with home sold)? Death (home in estate)?
  • Communicate with family. The inheritance impact should be transparent.

The wider message. Reverse mortgages are not inherently bad products — they solve real problems for retirees with substantial home equity and limited liquid resources. But the compounding mathematics is unforgiving over long horizons, and the product's true cost is rarely communicated as starkly in marketing materials as it should be. For the right borrower, with the right horizon, and (where eligible) using the HEAS alternative, the strategy works. For the wrong borrower or the wrong horizon, the compounding consumes most of what would otherwise be the family's inheritance.

The math is simple. The decision to borrow should reflect the math.

Sources

Key takeaways

  • Commercial reverse mortgage rates in Australia currently sit around 8.35-9.3%, so a $100,000 borrow compounds to roughly $511,000 after 20 years and $769,000 after 25 years.
  • The government's Home Equity Access Scheme (HEAS) charges a fixed 3.95%, unchanged since January 2022 — about $294,000 cheaper than a commercial loan on the same $100,000 borrow over 20 years.
  • The negative equity guarantee stops a borrower owing more than the home is worth at sale, but it doesn't protect the equity itself — a large enough borrow can consume the home's entire value.
  • For a $400,000 borrow on an $800,000 home appreciating at 4% a year, the loan overtakes the home's value at around year 17 at today's commercial rates — roughly a decade sooner than it would have at the older 7% rates.
  • For pensioners eligible for HEAS, it should be the default option; a commercial reverse mortgage is worth considering only when HEAS doesn't meet a specific need, such as a larger loan amount.

Frequently asked questions

How much does a $100,000 reverse mortgage actually cost over 20 years?

At a representative current commercial rate of 8.5%, a $100,000 reverse mortgage compounds to roughly $511,000 after 20 years and about $769,000 after 25 years, since no repayments are made along the way and interest compounds on the growing balance.

How much cheaper is the Home Equity Access Scheme than a commercial reverse mortgage?

HEAS charges a fixed 3.95% per annum, unchanged since January 2022, compared to commercial rates around 8.35-9.3%. On a $100,000 borrow, that's roughly $294,000 less debt after 20 years, and about $505,000 less after 25 years.

Does the negative equity guarantee protect a family's inheritance?

It only guarantees the borrower or estate will never owe more than the home is worth at sale — it doesn't protect the underlying equity. A large enough reverse mortgage can still consume the home's entire value over a long enough horizon, leaving little or nothing for heirs.

Who is a reverse mortgage appropriate for?

It suits asset-rich, cash-poor retirees with a shorter expected horizon (roughly 5-10 years) or those borrowing modest amounts relative to the home's value. It's generally less appropriate for retirees with 20+ years of expected retirement, those prioritising an inheritance for heirs, or anyone eligible for the cheaper government HEAS alternative.

A note on advice. This article is general information only and doesn't account for your personal circumstances. Everyone's situation is different — before acting, it's worth talking it through with a licensed adviser who knows your full picture.