Offset Account Deep-Dive
We covered offset basics in Module 1. Now let's go deeper, because this is the single most powerful loan feature available to Australian borrowers.
How Daily Interest Calculation Works
Most Australian home loans calculate interest daily. This is why offset works so well, every dollar sitting in offset reduces your interest charge that day.
Loan: $500,000 at 6.00%. Offset balance: $60,000.
Without offset: Daily interest = $500,000 x 6% / 365 = $82.19/day
With $60k offset: Daily interest = $440,000 x 6% / 365 = $72.33/day
Saving: $9.86/day = $3,600/year
Now imagine it's payday. Your $4,500 salary hits the offset on the 15th. Even though you spend most of it over the next 2 weeks, you get the benefit for every day it sits there. If your average balance across the month is $30,000, you're still saving $1,800/year vs a savings account earning maybe $900 after tax.
Offset is like earning your mortgage rate, tax-free, on your savings. No savings account in Australia can beat that after tax.
Maximise Your Offset
- Put everything in offset, salary, tax returns, bonuses, savings, emergency fund. All of it
- Use a credit card for daily spending, pay everything on the card during the month, then pay it in full from offset on the due date. This keeps your money in offset for an extra 30-55 days
- Multiple offset accounts, some lenders allow 2-3 offset accounts linked to one loan. Useful for separating "savings" from "spending" while both offset your loan
- Park rental income here, if you have an investment property, the rent should go into your home loan offset (not the investment loan, you want deductible debt to stay high)
Offset vs savings account: If your mortgage rate is 6%, every dollar in offset effectively earns you 6% tax-free. A savings account paying 5% actually pays ~3.25% after tax (at the 37% bracket). Offset wins by almost double. There is literally no reason to keep savings outside offset if you have a mortgage.
Rate Lock & Portability
Rate Lock
When you apply for a fixed rate loan, the rate isn't locked until settlement (which can be 4-8 weeks away). If rates go up during that time, you could get a higher rate than you applied for.
A rate lock guarantees today's fixed rate for a set period (usually 90 days). The cost is typically 0.10-0.15% of the loan amount.
You apply for a 2-year fixed rate at 5.49% on a $600,000 loan. Rate lock costs 0.15% = $900.
Between application and settlement, the RBA raises rates and that fixed rate jumps to 5.79%.
Without rate lock: You pay 5.79% = $3,708/month
With rate lock: You pay 5.49% = $3,600/month
Monthly saving: $108. Over 2 years: $2,592 saved for a $900 investment.
If rates had stayed the same or dropped, the $900 is lost. It's insurance, you pay for certainty.
Portability
Portability lets you take your existing loan with you when you sell one property and buy another. Instead of discharging and getting a new loan (with new fees, new application), you simply transfer the loan to the new property.
- Saves $500-$2,000 in discharge + new application fees
- Keeps your existing rate (important if you locked in a good rate)
- Most lenders offer this, but conditions apply, the new property must be acceptable and you may need a top-up if the new property costs more
- There's usually a time limit (e.g., sell and buy within 3-6 months)
When portability matters: If you're on a great fixed rate or a very competitive variable rate that's no longer offered, porting saves you from losing that rate. If your current rate is average, it's often simpler to just refinance to a new lender anyway.
Package Loans vs Basic Loans
Package Loan
Annual fee: $295-$395/year. Comes bundled with extras.
- Lower interest rate (usually 0.10-0.20% less)
- Free offset account
- Fee waivers on credit cards, insurance
- Rate discounts on additional loans
- Best for loans over $300,000
Basic / No-Frills Loan
No annual fee. Stripped-back features.
- Sometimes the lowest advertised rate
- No offset (or limited offset)
- May have restrictions on extra repayments
- Often no redraw or limited redraw
- Best for small loans or if you don't need features
$500,000 loan:
Package: 5.89% + $395/year fee = monthly cost $2,994 + $33 fee = $3,027
Basic: 6.04% + no fee = monthly cost $3,036
The package saves $9/month after the fee, not huge. But if you keep $40,000 in offset (only available on the package), the offset saves another $200/month. Total package advantage: $209/month.
If you have no savings to put in offset, the basic loan might actually win. The right choice depends on your situation.
The Traps: What Nobody Tells You
1. Honeymoon Rates
Some lenders offer a super-low introductory rate for the first 1-2 years, then revert to a much higher rate.
Example: Introductory rate of 5.29% for 12 months, reverting to 6.39% after. On a $500k loan, you save $3,300 in Year 1 but then pay $2,400/year more than market for the remaining 29 years. Most people forget to refinance when the honeymoon ends. The lender is banking on this.
2. Comparison Rate: Useful But Limited
The comparison rate includes the advertised rate plus most fees and charges, expressed as a single rate. It's meant to help you compare apples to apples. But:
- It's calculated on a $150,000 loan over 25 years, not relevant if your loan is $600k
- It doesn't include offset account savings
- It doesn't account for the fee structure of package loans vs basic loans at your loan size
- It's a starting point, not the final word
3. Clawback, What Your Broker Doesn't Want You to Know
Here's something most people don't know: when your broker places your loan, they receive a commission from the lender. If you refinance within the first 1-2 years, the lender claws back that commission from the broker.
What this means for you: A good broker won't discourage you from refinancing if it's in your interest, even if they lose their commission. But be aware of it. If your broker seems reluctant to help you refinance a loan they placed less than 2 years ago, this might be why. At Lendera, we'll always advise what's best for you regardless of clawback.
4. Cashback Offers, Do the Maths
Many lenders offer $2,000-$4,000 cashback for refinancing to them. Sounds great, but:
- The cashback lender's rate might be 0.10-0.20% higher than the best available
- On a $500,000 loan, 0.15% higher = $750/year extra interest
- A $3,000 cashback is spent in 4 years, but the higher rate lasts the life of the loan
- Always compare the total cost over 3-5 years, not just the upfront sweetener
5. Hidden Fees
| Fee | What to Watch |
|---|---|
| Annual package fee | $295-$395/year, only worth it if the rate discount exceeds the fee |
| Monthly account fee | $10-$15/month on some basic loans, adds up to $180/year |
| Offset fee | Some basic loans charge $10/month for an offset account |
| Extra repayment limits | Some fixed loans cap extra repayments at $10,000-$20,000/year. Excess attracts a fee |
| Settlement/discharge | $150-$400 when you leave. Not avoidable, but factor it in |
| Valuation fee | Most lenders waive for straightforward properties, but non-standard properties may cost $300-$600 |
Cut through the noise
A broker compares the total cost, not just the headline rate. We read the fine print so you don't have to.
Final Knowledge Check
Last set of questions across everything you've learned. You've earned this.
Why is an offset account effectively better than a savings account for someone with a mortgage?
A lender offers a honeymoon rate of 5.29% for 12 months reverting to 6.39%. On a $500k loan, after 3 years you would have:
The comparison rate is calculated on a loan of:
What is "clawback" in the context of mortgage broking?
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Academy Complete!
You've completed all 6 modules of the Home Loans Academy. You now understand more about home loans than most Australians, and more than some bank employees.
What you know now:
Or revisit any module anytime.