Your Bank Is Charging You Too Much Interest. Here's How to Fix It in One Phone Call.

I am going to teach you something that will save you between $2,000 and $8,000 per year. It takes one phone call. It requires zero paperwork. And your bank is praying you never find out about it.

In Australian banking, there is an unwritten rule so blatant it borders on insulting: the longer you stay with a bank, the higher your interest rate drifts relative to what new customers receive. Banks call this "back-book pricing." Consumer advocates call it loyalty tax. I call it a wealth transfer from the passive to the informed.

Back-book pricing is an industry-wide habit rather than one bank's quirk: lenders compete hardest for the borrower they do not have yet, and the discount you negotiated at origination does not automatically follow the market down. Do the arithmetic on your own loan and it stops being abstract. On a $600,000 investment loan, 50 basis points is $3,000 a year. Three years without repricing is $9,000 of interest you did not have to pay.

That is not pocket change. That is the deposit on your next investment property's stamp duty.

The one phone call that saves thousands

Here is exactly what you do. Pick up the phone. Call your bank. When the automated system asks what you need, do not say "existing loan enquiry." Say: "I want to speak to the loan retention department."

Loan retention. Remember those two words.

This is the department whose sole job is to prevent you from leaving. They have authority to offer rate discounts, fee waivers, and cashback incentives that the regular customer service team cannot access.

When you get through, be direct. Do not apologise. Do not explain your life story. Say this:

"I have been reviewing my loan and I have been quoted a better rate elsewhere. Unless you can match or beat it, I will be refinancing. I need your best retention rate today."

Only say that if it is true. Get a real quote first — from a broker, or from another lender's own advertised rate — so the threat is credible and you are not making something up to a credit provider.

That is it. No negotiation wizardry required. No MBA needed. Just the credible threat of departure.

In our experience as a Melbourne buyers agent helping clients manage their loan portfolios, this single phone call typically produces a rate reduction of 20-50 basis points. On a $600,000 loan, that is $1,200-$3,000 per year — achieved in a fifteen-minute conversation.

"It is the same logic as bargaining at a market stall. You say 'give me a better price or I walk.' The bank's retention department exists because walking is exactly what they do not want you to do." — Yan Zhu, PremiumRea

The two-year refinance cycle

The retention call is a short-term fix. For a structural solution, you need a refinancing rhythm.

We advise our clients to reassess their loan every 18-24 months. Not necessarily to refinance — sometimes the retention offer is sufficient — but to benchmark. The Australian mortgage market is intensely competitive, with banks offering cashback incentives of $2,000-$4,000 to attract refinancers.

Here is how the cycle works in practice:

Month 1-18: You are on your current loan. Interest rate is competitive because you negotiated at origination.

Month 18: Call the retention department. Secure a rate reduction. If the reduction is meaningful (20+ basis points), stay for another 12 months.

Month 24-30: If the retention offer was inadequate, or if competitor cashback offers have increased, initiate a formal refinance. A refinance is mostly a paperwork exercise; how long it takes depends on the incoming lender's assessment queue and on how fast you produce payslips, tax returns and rental statements.

The cashback alone often covers the legal and discharge fees. Net result: a lower rate, a few thousand dollars in cash, and a reset of the loyalty-tax clock.

Over a decade-long investment holding period, this cycling saves $20,000-$40,000 in interest costs. That is a granny flat's worth of savings, simply from refusing to be a passive borrower.

One structural point worth understanding, and it is about channels rather than about any particular bank. Going direct means you see one lender's pricing, one servicing calculator and one credit policy, and you either fit it or you don't. Going through a broker means someone compares several — which matters most when your income is complex, when rental income is being shaded, or when your LVR sits on the edge of a tier. Neither channel is free of an incentive: a broker is paid by the lender that writes the loan, and a lender's own banker is paid by that lender. So in both cases ask who is paying whom, and how much.

We introduce clients to independent brokers, accountants and solicitors and take no referral fee from any of them. We are not licensed to give credit or financial product advice — which lender and which channel suit your circumstances is a question for someone who is.

August 2026 update: rate levels move, which is why this article deliberately deals in gaps rather than absolute numbers — the loyalty-tax spread between back-book and front-book pricing is what the retention call attacks, whatever the cash rate is doing. Before any call, pull the current cash rate target directly from the Reserve Bank of Australia (rba.gov.au/statistics/cash-rate/) and your own rate from your latest statement. The negotiation case is the documented spread between what your lender offers new customers on your identical loan profile and what you are paying — not a number anyone quotes you over the phone.

Interest-only versus principal-and-interest: the investment tax equation

While we are talking about loan structure, let me address the single most common mistake I see in investment loan setup.

The majority of investment property owners in Australia are on principal-and-interest (P&I) loans. This is almost always wrong for investment properties.

Here is why. On an investment loan, the interest component is 100% tax deductible. The principal repayment component is not deductible at all. By choosing P&I, you are voluntarily reducing your tax deduction by paying down non-deductible principal.

The smarter structure: interest-only (IO) on investment loans, and direct any surplus cash into the offset account attached to your owner-occupied loan (where the interest is not tax deductible).

The rate differential between IO and P&I is typically 10-30 basis points. On a $600,000 loan, that is $600-$1,800 per year in additional interest cost. But the tax benefit of maintaining maximum deductible interest easily exceeds this differential for anyone in the 37% or 45% marginal tax brackets.

At a 37% marginal rate, every $10,000 in investment loan interest generates $3,700 in tax savings. At 45%, it generates $4,500. Those savings compound year after year, whereas the P&I approach slowly erodes your deduction base while building equity in the wrong asset (your investment property instead of your home).

"The only debt you should be paying down is the one attached to your home — because that interest is not deductible. Investment loan interest is a tax asset. Preserve it." — Yan Zhu, PremiumRea

Frequently asked questions

Will calling the retention department hurt my credit score? No. Calling your existing bank does not generate a credit enquiry. Only formal loan applications to new lenders create hard enquiries on your credit file. The retention conversation is internal to your existing bank.

How often can I refinance without it looking bad? Every 18-24 months is standard and will not raise red flags. Multiple refinances within 12 months may make lenders cautious, as it suggests you are churning for cashback rather than genuinely managing your finances.

Is it worth refinancing for less than 30 basis points? Probably not, once you factor in discharge fees ($300-$400) and the time involved. The sweet spot is 40+ basis points or a cashback offer exceeding $3,000. Below that threshold, call retention instead.

Can self-employed borrowers use this strategy? Absolutely. Self-employed borrowers (ABN holders with 18+ months of trading history and GST registration) often pay higher rates by default. The retention call is even more valuable, as the alternative — a full refinance with new documentation requirements — is more burdensome for self-employed applicants.