Second mortgage vs refinance: keep the first loan, or replace it?

What’s the core difference?

Both options turn property equity into business funds. They differ in what happens to the loan you already have.

• Second mortgage: your first loan stays exactly as it is. A new lender registers a mortgage behind it and lends against the remaining equity.
• Refinance: a new lender pays out your first loan and lends you a larger amount, secured by a new first mortgage. The old loan disappears.

How do they compare side by side?

	Second mortgage	Refinance
Existing loan	Unchanged	Paid out and replaced
Speed	Often days; same day possible for $20k–$250k	Usually weeks
Paperwork	Leans on equity and exit; low doc possible	Full financials usually required
Pricing	Higher, reflecting second ranking	Often lower for strong borrowers
Upfront costs	New loan costs only	Discharge of old loan plus new loan costs, possibly break costs
Term	Usually short to medium	Often long
Credit issues, ATO debt	Considered case by case	Often harder with mainstream lenders
First lender involved?	Consent may be needed	Yes, to discharge

When does a second mortgage win?

• Speed matters. A tax deadline, a supplier, a settlement or payroll can’t wait for a refinance.
• You’d lose something by refinancing. A fixed rate with break costs, a feature your household relies on, or simply a relationship you want to keep.
• The amount is small relative to the first loan. Refinancing a $700,000 loan to raise $120,000 moves a lot of money to solve a small problem.
• Your paperwork isn’t refinance-ready. Lodgements behind, recent trading not yet in the financials, or a credit blemish that a mainstream lender won’t look past today.
• ATO debt is part of the picture. Many mainstream lenders are reluctant while tax debt is outstanding, and the ATO may report business tax debts of $100,000 or more overdue by 90 days where the business isn’t engaging. Clearing it first can make a later refinance easier. See second mortgages for ATO debt.

When does a refinance win?

• The need is long-term. Funding that will take years to repay is usually better on a longer, cheaper facility.
• Your financials are strong and current. You’ll qualify for mainstream terms.
• There’s no time pressure. Weeks don’t matter.
• The first loan is expensive or restrictive anyway. Replacing it is a benefit in itself.

What’s the two-step plan many owners use?

Use a second mortgage to solve the immediate need, then refinance both loans into one once the business is in a stronger position: the ATO debt is cleared, the growth shows in the financials, or the returns are lodged. The second mortgage’s term is set to cover that journey with a margin, and the refinance becomes its exit plan.

This sequence is often cheaper overall than forcing a refinance too early, when the business looks at its weakest on paper.

Not sure which path fits? Describe your situation and a specialist will lay out both.

How should you compare costs?

Avoid comparing only ongoing pricing. For each option, estimate the total cost in dollars over the period you’ll actually hold it:

• Second mortgage: establishment, legal, valuation and discharge fees, plus interest for the expected term.
• Refinance: discharge and any break costs on the old loan, new establishment, legal and valuation fees, plus interest on the whole refinanced balance.

Remember the refinance puts a new price on your entire balance, not just the new money. If your first loan is well priced, refinancing all of it to raise a modest amount can be the costlier choice. Our costs page lists the fees to ask about.

Illustrative example: the same need, two paths

An owner with a $1,100,000 home and a $600,000 fixed-rate loan needs $150,000 for stock within a week. A refinance would involve break costs on the fixed rate, full financials, and several weeks. A second mortgage settles within days at a combined LVR of about 68%, and is refinanced with the main loan when the fixed period ends in 14 months. The figures are illustrative.

What does your first lender think of either option?

With a refinance, your first lender loses the loan, so expect it to make a retention offer or at least ask why you’re leaving. With a second mortgage, it keeps the loan and may be asked to consent. Neither is a problem, but it’s worth knowing that your current lender’s attitude can shape both timing and cost. Some owners discover during the process that their existing lender would rather increase the loan itself than consent to a second mortgage; that’s a top-up, covered next.

Where do bank top-ups and caveats fit?

Two more pathways sit alongside these. A top-up with your existing lender increases your first loan without changing lenders; it can be cheap but is often slow and income-tested. A caveat loan is a very short-term option that can be marginally faster than a second mortgage. See second mortgage vs bank top-up and second mortgage vs caveat loan. The pathway comparison in our LVR calculator puts all three side by side.

Let’s work out which path is yours

The right answer depends on your timeline, your first loan and your paperwork, and a specialist can usually tell you in one call. Enquiring takes about 60 seconds and involves no credit check when you first enquire.

We keep your details with a single specialist rather than distributing them to a row of lenders. They’ll compare both paths against your actual numbers and call you back. Please tell us about your first loan, including any fixed-rate period, as accurately as you can; it’s often the detail that decides the answer.

Compare both paths for my business →