Lenders Mortgage Insurance (LMI): Do You Really Need a 20% Deposit?

Short answer

Lenders mortgage insurance (LMI) is a one-off cost that kicks in when your deposit is less than 20%. It protects the bank, not you, and it can add thousands to the cost of buying. But sometimes paying LMI to buy sooner makes more sense than renting for another few years while you save — especially now that the First Home Guarantee lets many first home buyers skip it entirely.

What LMI actually is (and what it isn't)

Let's clear up the biggest confusion first. LMI protects the lender, not you. If you borrow more than 80% of a property's value and then default, the lender uses LMI to cover its losses. You still owe the money — LMI won't help you if you lose your job.

It's completely different from mortgage protection insurance, which does cover you if you can't work due to illness or injury. The easy way to remember it: LMI is for the bank, mortgage protection is for you.

When do you pay it?

The magic number is 20%. Put down a 20% deposit and there's no LMI. Borrow more than 80% of the property's value — a loan-to-value ratio (LVR) above 80% — and LMI usually applies.

The smaller your deposit, the higher the premium, because the lender sees you as a bigger risk.

How much does it cost?

It's a sliding scale, not a flat fee. As a rough guide, LMI is typically around 1–3% of the loan amount, and it climbs the closer you get to a 95% LVR.

Worked example: You're buying a $600,000 home with a 10% deposit ($60,000), so you borrow $540,000 at a 90% LVR. Your LMI premium might land around $10,000–$15,000 depending on the lender. You can usually add it to the loan (repaid over the life of the mortgage, with interest) or pay it as an upfront lump sum.

The question that actually matters: wait or buy now?

This is where it stops being a simple maths problem and becomes a family decision. Say you're renting at $600 a week — over $31,000 a year going to someone else's mortgage. If LMI costs you $12,000 but gets you into your own home two years sooner, you've saved roughly $62,000 in rent, well above the premium.

There's a real trade-off, though: you're paying interest on a larger loan (and on the LMI if you capitalise it), and you'll have less equity if prices dip. But for most growing families, the "buy sooner" side usually wins when the alternative is renting for years.

Three ways to avoid LMI entirely

1. Save a 20% deposit. The cleanest option, but slow — especially with prices where they are in 2026.
2. First Home Guarantee (FHBG). If you're a first home buyer, you may be able to buy with as little as a 5% deposit and no LMI, because the government guarantees up to 15% of the loan (I covered the grants and schemes in more detail here). There's also the Family Home Guarantee for single parents, letting them buy with a 2% deposit. This is the single biggest LMI shortcut for Australian families.
3. A guarantor or LMI waiver. Some lenders waive LMI for certain professions (doctors, lawyers, accountants) even under a 20% deposit, and a family guarantor using their own property as security can also remove the need for it.

What I'd tell a friend

Don't treat the 20% deposit as a hard rule that keeps you renting for years. If you're a first home buyer, check the First Home Guarantee first — it's the reason so many families now buy with a 5% deposit and never see an LMI bill. And if you do pay LMI, run the numbers on rent saved versus the premium; more often than not, buying sooner leaves you better off.