Loan-to-Value (LTV): The One Ratio That Sets Your Rate

Lenders in every market boil a mortgage application down to one number before anything else: how much you're borrowing against what the property is actually worth. That's loan-to-value, called LVR (loan-to-value ratio) in Australia, and it sets your interest rate tier, whether you need mortgage insurance, and how much room you have to refinance later.

The formula, and why it isn't complicated

LTV is simply your loan amount divided by the property's value, expressed as a percentage:

LTV = (loan amount ÷ property value) × 100

Buy a $400,000 home with a $40,000 down payment (10%), and your loan is $360,000. Divide $360,000 by $400,000 and you get 90% LTV. The lower the percentage, the less risk the lender is carrying relative to the asset securing the loan, and pricing follows accordingly.

Why lenders price in bands, not a smooth curve

Rates don't decline smoothly as LTV drops. Lenders set pricing in discrete bands, commonly around 60%, 70%, 80%, 90%, and 95% LTV, with a rate step at each threshold rather than a continuous adjustment. A borrower at 79% LTV and a borrower at 81% LTV can be quoted meaningfully different rates, even though the actual risk difference between those two numbers is tiny. If your LTV sits just above a band, it's worth checking whether a slightly larger down payment (or paying down a small amount before closing) crosses you into the cheaper tier.

The 80% line is the one most borrowers have heard of, because it's also the threshold tied to mortgage insurance in several markets: above 80% LTV, US lenders require PMI and Canadian lenders require CMHC-equivalent default insurance by federal regulation, while Australian lenders require LMI above 80% LVR. (How those three insurance products actually work, and how differently each one behaves, is covered in a separate article on PMI, LMI, and CMHC compared.)

How LTV changes after you close

LTV isn't fixed at the day of purchase; it moves in two ways, and the two effects stack on top of each other.

Paydown. Every scheduled payment reduces your loan balance a little, which lowers the numerator in the LTV calculation even if the property value never changes.

Appreciation (or depreciation). If the property's value rises, the denominator grows, which lowers LTV further, independent of anything you've paid. If value falls, the opposite happens, and LTV can rise even while you keep paying on schedule.

Take that same $400,000 home with a $360,000 loan (90% LTV) at 6.5% on a 30-year term. After 5 years (60 monthly payments of $2,275.44), the balance has fallen to about $337,000. If the home has also appreciated at a modest 3% a year over that period, it's now worth roughly $463,700. Recalculate LTV using the appreciated value and you get about 72.7%, comfortably past most lenders' 80% and even 75% pricing thresholds. Using paydown alone, with no appreciation assumed, the same 5 years only gets you to about 84.2% LTV, still above the 80% line. Appreciation, when it happens, typically does more work than scheduled paydown alone in the first several years of a loan.

Why this matters when you refinance

A lender assessing a refinance application recalculates LTV using a current appraised value, not your original purchase price. This cuts both ways. If your area has seen strong price growth, you may have crossed into a materially better pricing tier without doing anything beyond making your regular payments, and refinancing could get you a lower rate purely on improved LTV. If values have been flat or falling, your LTV may not have improved as much as you'd expect from paydown alone, or could even have worsened, which is worth checking before you assume a refinance will automatically qualify you for better pricing.

This is also why a new appraisal, not just your own estimate of value, is the number that actually counts. Online home-value estimates are a reasonable planning tool, but the lender's own appraisal at the time of application is what determines your real LTV for pricing and insurance purposes.

Combined LTV, when there's a second loan involved

If you're using a second mortgage, a home equity line, or a piggyback loan alongside your primary mortgage, lenders typically look at combined loan-to-value (CLTV): the total of all loan balances secured against the property, divided by its value. A $400,000 home with a $320,000 first mortgage and a $40,000 HELOC has a CLTV of 90%, even though the first mortgage alone sits at 80%. Confirm which figure (LTV or CLTV) a specific lender is quoting against, since the two can differ significantly once a second loan is in the picture.

Get a current number, not a stale guess

Don't rely on a rough estimate of what you think your property is worth; get a current, lender-grade valuation, and calculate the ratio against your actual current loan balance, not your original loan amount. A few percentage points in either direction can move you across a pricing band, an insurance threshold, or a refinance eligibility line, and that's a meaningfully different outcome from what a stale estimate would have suggested.