LMI vs 20% Deposit on a First Home: When the Maths Tips

TL;DR

The 20% deposit benchmark is a banking convention, not a legal requirement. Lenders accept smaller deposits — typically down to 5% — but charge Lender's Mortgage Insurance (LMI) to cover their risk on the lower-deposit loan. For a first home buyer choosing between (a) waiting another year or two to save the full 20% and (b) buying now with a 10% or 5% deposit and paying LMI, the right answer depends on three numbers: the LMI premium, the property's expected price drift, and the rent you would otherwise pay during the saving period.

The federal First Home Guarantee scheme (run by Housing Australia, formerly NHFIC) sidesteps this for eligible first home buyers entirely: with a 5% deposit, the government guarantees the gap up to 20%, so the lender does not charge LMI. The 2025-26 cap is 35,000 places per financial year, with property price caps that vary by state and metro/regional zone.

This guide walks through the LMI premium structure, the First Home Guarantee scheme rules, the cost-of-waiting trade-off, and three worked examples — Sydney unit at $750,000, Melbourne house at $850,000, and Brisbane unit at $620,000 — that show where the maths actually tips.

How LMI is priced

Lender's Mortgage Insurance is not insurance for the borrower. It protects the lender against loss if the borrower defaults and the property sells for less than the outstanding loan balance. The borrower pays the premium but receives no payout — it is a risk-transfer fee charged at loan origination.

The premium is calculated on:

Loan-to-value ratio (LVR). LMI scales steeply with LVR. A 90% LVR loan typically attracts LMI of 1.5% to 2.5% of the loan amount. A 95% LVR loan can attract LMI of 3% to 4.5% of the loan amount.
Loan amount. Bigger loans cost more in absolute dollars and slightly more as a percentage (the bands typically tier).
Loan-to-income. Some insurers charge more if the loan is large relative to the borrower's income.
Property type and location. Inner-city units and "high-density risk" postcodes can attract surcharges.

A typical premium grid (illustrative — actual premiums vary by lender and insurer):

LVR	Loan amount	Approximate LMI premium
80–85%	$400,000	0.5% × $400,000 = $2,000
85–90%	$500,000	1.5% × $500,000 = $7,500
90–95%	$600,000	3.0% × $600,000 = $18,000
95%	$700,000	4.0% × $700,000 = $28,000

Most lenders allow the LMI premium to be capitalised into the loan (added to the principal). This means you do not need to find the cash up front, but you pay interest on it over 25 to 30 years. A $20,000 LMI premium capitalised at 6% over 30 years costs about $43,000 in total repayments.

The two main LMI insurers in the Australian market are Helia (formerly Genworth) and QBE LMI; some lenders also offer in-house "Low Deposit Premium" (LDP) products that are functionally equivalent. The premium is non-refundable. If you refinance to a different lender, you generally pay LMI again on the new loan if the LVR is still over 80%.

The First Home Guarantee scheme

The First Home Guarantee (FHBG) is administered by Housing Australia under the National Housing Finance and Investment Corporation Act 2018. It guarantees the gap between a 5% deposit and the 20% LMI threshold, so the lender treats the loan as effectively 80% LVR and waives LMI. The borrower pays the loan back to the lender as normal; the guarantee is invisible day-to-day.

ASIC's MoneySmart and the Housing Australia website publish the property price caps, eligibility criteria, and place allocations. The key FY2025-26 settings:

35,000 places per financial year.
Eligibility: Australian citizens or permanent residents, age 18+, single income up to $125,000 or couple income up to $200,000, first home buyers (or have not owned property in the last 10 years).
Property price caps (FY2025-26):

State	Capital city / regional centre	Rest of state
NSW	$900,000	$750,000
VIC	$800,000	$650,000
QLD	$700,000	$550,000
WA	$600,000	$450,000
SA	$600,000	$450,000
TAS	$600,000	$450,000
NT	$600,000	n/a
ACT	$750,000	n/a

The scheme also has sister products: the Family Home Guarantee (single parents, 2% deposit) and the Regional First Home Buyer Guarantee (focussed on regional areas). Place allocations between the three are set by Housing Australia each year.

A borrower under the FHBG saves the full LMI premium — typically $15,000 to $25,000 on a 5% deposit purchase. That is real money in pocket relative to a non-FHBG 5% deposit purchase. The trade-off is the 35,000-places-per-year cap is competitive; the scheme reopened on 1 July 2025 with places filling rapidly.

The cost-of-waiting trade-off

The classic argument for paying LMI is "the property will appreciate while I wait, and the appreciation will outpace the LMI premium". The maths:

Buy now at $750,000 with 10% deposit + LMI of $14,000.
Wait 18 months to save full 20% deposit ($150,000 instead of $75,000), property prices rise 6% over the period.

Cost of waiting:

Property price at purchase: $750,000 × 1.06 = $795,000.
Extra purchase price: $45,000.
Stamp duty differential (NSW with FHBAS exemption ceiling at $800,000): the original $750,000 was fully exempt; the $795,000 is still exempt. No extra stamp duty in this corridor.
Rent paid over the 18 months: $600/week × 78 weeks = $46,800.

Total cost of waiting: $45,000 + $46,800 = $91,800. Cost of LMI route: $14,000.

In this scenario, LMI wins by ~$78,000.

But change the assumptions:

Property prices flat over 18 months.
Rent lower at $400/week.
Total cost of waiting: $0 + $31,200 = $31,200.
LMI route still wins by ~$17,000.

And again:

Property prices fall 5% over 18 months.
Rent at $400/week.
Cost of waiting: −$37,500 + $31,200 = −$6,300 (you save $6,300 by waiting in nominal terms).
LMI route loses by ~$20,300.

The break-even depends overwhelmingly on price drift assumptions. Treasury's Intergenerational Report and ABS Residential Property Price Index show long-term capital city growth of 6–8% nominal per annum, but recent volatility (2022 down 6%, 2023 up 9%, 2024 up 4–5%) means the next 12–18 months can swing either way. The break-even rent (where waiting is neutral against an LMI of $15,000 over 18 months) is roughly $200/week at flat prices — almost any actual rent makes waiting more expensive than the LMI on flat-price assumptions.

Official source

Housing Australia — First Home Guarantee — Scheme Rules FY2025-26 — the authoritative reference.
ASIC's MoneySmart — Lenders Mortgage Insurance — independent overview and worked examples.
National Housing Finance and Investment Corporation Act 2018 (Cth) — the legislated framework.
ABS — Residential Property Price Indexes — quarterly data for trend analysis.
the ATO — First Home Super Saver Scheme — separate product worth pairing with FHBG.

Worked examples

Example 1 — Sydney unit, $750,000, 10% deposit

Purchase price: $750,000
Deposit: $75,000 (10%)
Loan amount: $675,000 (90% LVR)
LMI premium (typical): 1.7% × $675,000 = $11,475
Stamp duty (NSW FHBAS, new home): $0 (under the $800,000 full-exemption threshold)
Capitalised LMI: $11,475 added to loan. New loan: $686,475.
Monthly repayment at 6.0% over 30 years: $4,118 vs $4,049 without LMI capitalised. Difference: $69/month, $828/year.

Compared to the alternative — wait 18 months, save extra $75,000, property rises 5%, rent $550/week:

New price: $787,500.
Saved LMI: $11,475.
Lost capital appreciation: $37,500.
Rent paid in waiting: $42,900.
Net cost of waiting vs LMI route: $69,000 worse.

Buy now with LMI on these assumptions. The threshold flips only if Sydney property prices fall by more than ~6% over the 18 months and rent is below $300/week — neither realistic in current conditions.

If the buyer is FHBG-eligible: buy now with $0 LMI, save $11,475 outright. Always check FHBG eligibility first.

Example 2 — Melbourne house, $850,000, 5% deposit + FHBG

Purchase price: $850,000 (over the VIC capital-city cap of $800,000 — not FHBG eligible)
Adjust scenario: same buyer, looks at $780,000 instead.
Deposit: $39,000 (5%)
Loan amount: $741,000 (95% LVR)
LMI without FHBG (typical): 4.0% × $741,000 = $29,640
LMI with FHBG: $0 (saved)
Stamp duty (VIC PPR concession at $780,000): around $30,500 (concessional rate applies above $600,000).

The FHBG saves $29,640 outright on this Melbourne house. The trade-off: the 35,000-place cap is competitive; if the buyer misses out on a place, they would face the full LMI. Application opens annually on 1 July with most places allocated by August/September in recent years.

If the buyer instead saves to a 20% deposit:

20% deposit on $780,000: $156,000.
Time to save extra $117,000 on a $90,000 income with $1,200/month savings rate: 8 years (or ~3 years with First Home Super Saver layered in).
Property price drift over 8 years (assume 5% nominal pa): $780,000 → $1,153,000.
Required deposit: $230,600.
New shortfall: $74,600 → another 5+ years of saving.

Most first home buyers in Melbourne cannot wait 8+ years. The FHBG with 5% deposit is the realistic path for buyers under the price caps.

Example 3 — Brisbane unit, $620,000, 12% deposit

Purchase price: $620,000 (under QLD capital-city cap of $700,000)
Deposit: $74,400 (12%)
Loan amount: $545,600 (88% LVR)
LMI without FHBG (88% LVR): 1.0% × $545,600 = $5,456
LMI with FHBG: $0 (saved). But: FHBG requires 5% minimum deposit and is most cost-effective at the 5–10% range. At 12% the buyer has already done most of the saving.

A practical question: should the buyer keep the extra $24,400 (the 8% they have over the 5% minimum) and use FHBG, or use the full $74,400 and avoid LMI without FHBG?

FHBG path: 5% deposit ($31,000), full FHBG loan, no LMI. Buyer keeps $43,400 in offset/savings. Loan: $589,000. Monthly repayment: $3,533.
No-FHBG path: 12% deposit ($74,400), 88% LVR, LMI $5,456 capitalised. Loan: $551,056. Monthly repayment: $3,305.

The FHBG path has a higher loan but the extra $43,400 in offset reduces interest paid. If the buyer applies the $43,400 against the loan in offset, the effective loan becomes $545,600, identical to the no-FHBG loan, but the monthly repayment is computed on $589,000 — so monthly repayments are ~$228 higher unless the offset is structured correctly. Most lenders allow the FHBG loan to have an offset account, and the offset reduces interest but not minimum repayment. The cash outcome is therefore very similar; the real difference is the avoided $5,456 LMI premium.

Verdict: if FHBG-eligible, the FHBG path saves $5,456 outright and gives more cash flexibility. The 12% deposit case is the closest call in this guide because the LMI premium is small, but the FHBG path still wins on absolute dollars saved.

Common pitfalls

Treating LMI as "wasted money". It is a risk-transfer fee. Without it, lenders would charge a higher rate on low-deposit loans, or refuse them. The economic question is whether the LMI premium is cheaper than the cost-of-waiting alternative — usually yes, especially in rising markets.
Ignoring the FHBG. Many first home buyers do not know about the scheme or assume they will not qualify. The income limits ($125,000 single / $200,000 couple) catch a wide population of professional first home buyers. Always check eligibility before paying LMI.
Forgetting the FHBG places fill quickly. The annual quota of 35,000 typically fills within the first 4–6 months of the financial year. Apply early via a participating lender. Housing Australia publishes a "places remaining" indicator.
Capitalising LMI without modelling the long-run cost. A $15,000 capitalised LMI at 6% over 30 years costs about $32,000 in total repayments. The $15,000 sticker shock understates the real cost.
Ignoring stamp duty interactions. Many states' first home buyer stamp duty concessions have price ceilings ($800,000 NSW, $750,000 VIC) that align imperfectly with the FHBG caps. A purchase at $810,000 in NSW loses the FHBAS exemption (paying full stamp duty) and exceeds the FHBG cap of $900,000 — so neither concession applies. Check the price corridors carefully before signing a contract.
Refinancing without re-paying LMI. If you refinance from Lender A to Lender B and your LVR is still over 80%, Lender B charges LMI on the new loan. The Lender A premium is non-transferable. Many borrowers refinance to chase a 0.2% rate cut and find the LMI wipes out the saving over 5+ years.
Confusing LMI with title insurance or mortgage protection insurance. LMI protects the lender. Title insurance protects the buyer against title defects. Mortgage protection insurance pays your mortgage if you cannot work due to illness or unemployment. Three different products, three different premiums.
Assuming First Home Super Saver and FHBG are mutually exclusive. They are not. The FHSS lets you contribute up to $50,000 of voluntary super contributions and withdraw them with earnings for a first home deposit. The FHBG is the lender-side guarantee. Layering both is the most tax-efficient first-home-buyer path for most professional buyers under the income caps.

How rate cuts and rises affect the maths

The cash-rate environment matters. When rates fall, the cost-of-waiting argument weakens — borrowers can afford a larger loan, and prices typically rise. When rates rise, borrowing capacity falls and prices typically soften, which can make waiting financially attractive.

A 0.5 percentage point rate rise on a $675,000 loan over 30 years adds about $200/month to the repayment. Over 18 months that is $3,600 of extra interest cost — comparable to a third of a typical LMI premium. The break-even between buying now and waiting therefore tightens in a rate-rising environment, which is why buyer activity slows materially when the RBA tightens.

The Reserve Bank's Statement on Monetary Policy (quarterly) and the rba.gov.au cash rate decisions are the authoritative trackers. Property price expectations are inevitably noisy, but the RBA's statements are the cleanest read on the rate trajectory.

Family pledge as an alternative to LMI

Some lenders accept a "family pledge" or "family guarantee" loan, where a parent's property equity is pledged as additional security so the borrower's effective LVR drops below 80% without LMI. The pledged amount is typically released back to the parent once the borrower's LVR drops to 80% naturally through repayment plus appreciation.

The trade-off: the parent has their property at risk if the borrower defaults. Most parents are not advised to pledge unless the borrower is on a very stable income and the pledge amount is small relative to the parent's net assets. Family pledge is more common in regional Australia where 5%-deposit buyers without FHBG access struggle to find competitive LMI quotes.

State-by-state stamp duty interactions

Stamp duty concessions for first home buyers vary materially by state. The interaction with FHBG and LMI maths can decide whether a deal stacks up:

NSW: FHBAS gives full exemption to $800,000 and tapered concession to $1,000,000 for new and existing homes. The price corridor that pairs FHBG (cap $900,000 capital city) and FHBAS full exemption is up to $800,000. Above $800,000 the buyer pays partial stamp duty plus is still FHBG-eligible up to $900,000.
VIC: PPR concession at $600,000 plus a first home buyer duty exemption to $600,000 with concession to $750,000. FHBG cap is $800,000 capital city. There is a $50,000 corridor ($750,000 to $800,000) where the buyer is FHBG-eligible but pays full stamp duty.
QLD: First home concession to $700,000 (full exemption to $700,000 from August 2024). FHBG cap is $700,000 capital city. The two align cleanly — anything under $700,000 is double-concessioned.
WA: First home owner stamp duty concession to $450,000 (full exemption) and concessional rate to $600,000. FHBG cap is $600,000. Aligned.

The point is a small price difference can swing tens of thousands of dollars in concessions. A $810,000 Sydney unit just over the FHBAS full-exemption ceiling pays around $20,000+ in stamp duty that an $800,000 unit avoids. Meanwhile both are FHBG-eligible. Always model the precise corridor before committing.

Genuine savings test and the 5% deposit rule

Most lenders require evidence that at least part of the deposit is "genuine savings" — money you have saved over time rather than received as a gift or windfall. Typical lender requirements: at least 5% of the property price held in savings for at least 3 to 6 months, with regular contributions visible on bank statements.

The First Home Guarantee scheme enforces a similar genuine-savings expectation through the participating lenders. A buyer who receives a $50,000 family gift can apply that gift to the deposit but cannot claim the gift itself as the genuine-savings minimum — they need separate evidence.

This catches buyers who have planned to combine FHSS withdrawals with a family gift and a small genuine-savings amount. Most lenders will accept a $20,000 FHSS release plus a small monthly savings record as the 5% genuine savings, provided the regular monthly savings amount is consistent and recent. Best practice: maintain a $200/week direct debit into a savings account for at least 6 months before applying.

What to watch for in the next Budget cycle

The Federal Budget night (the second Tuesday in May) is where the FHBG places allocation and price caps are typically refreshed. Two items worth flagging:

Place allocation. The 35,000 places have been steady since 2024. Budget submissions from the property industry have called for an increase to 50,000+; Treasury responses have been cautious. Expect modest changes only.
Price caps. The state caps are reviewed annually. Sydney and Melbourne caps lifted by 5–8% from FY2024-25 to FY2025-26 to reflect price inflation. Expect similar percentage adjustments at the next Budget.

We update this article each May after the Federal Budget. The "Updated" date at the top of the page is the version you are looking at.

Related calculators

Stamp Duty Calculator NSW — pair with FHBAS to model the NSW first home stamp duty path.
Stamp Duty Calculator VIC — Victoria's PPR concession and first home buyer settings.
First Home Super Saver Calculator — the parallel ATO scheme that lets first home buyers save inside super at concessional tax rates.
HECS-HELP Repayment Calculator — many first home buyers also have a HECS debt; the repayment ladder eats into mortgage serviceability.
Property Depreciation Calculator — for first home buyers later moving the property to investor status.

This article is general information based on the legislated FY2025-26 First Home Guarantee scheme and standard LMI structures. It is not personal financial advice; speak to a licensed mortgage broker, registered tax agent or conveyancer for your specific situation. The figures will be revisited each May after the Federal Budget.