← Back to blog

Offset Account vs Savings Account: Which Wins in Australia?

Woman comparing offset and savings balances

If you have a home loan and spare cash, an offset account usually beats a savings account. The reason is tax. Offset savings are measured at your mortgage rate and are not taxed. Savings interest is taxed at your marginal rate. A savings account only comes out ahead when you have no linked loan, when your loan has no offset, or when a bonus rate is high enough to beat your after-tax mortgage rate. That is rare.

The rest of this guide shows the arithmetic, the cases where a savings account still makes sense, and the traps that make an offset less valuable than it looks.

Aerowealth
Compare Your Retirement Scenarios
Model how mortgage and property decisions can affect your projected retirement income, age, and net worth with AeroWealth.
Explore AeroWealth

TL;DR

  • An offset account reduces the balance your lender charges interest on, so each dollar saves you interest at your loan rate. It is not income, so it is not taxed.
  • Savings interest is assessable income. Its real value is the after-tax rate, which is lower than the advertised one.
  • A rough rule: divide your mortgage rate by (1 minus your marginal tax rate including Medicare). A savings account needs to pay at least that to match an offset.
  • Offset wins less often when your balance is small, when the loan carries a higher rate or fee for the offset feature, or when the loan is an investment loan and you care about deductions.

Table of Contents

How each account actually pays you

The two accounts look similar in your banking app, but they work in opposite directions.

A savings account pays you. The bank credits interest to your balance, and that interest goes into your tax return. An offset account pays you indirectly. Moneysmart describes it as a transaction account linked to your home loan, generally available with a variable rate loan. The balance reduces the amount of the loan on which interest is charged. Moneysmart’s own example: on a $750,000 loan with $50,000 in the offset, you pay interest on $700,000.

Three consequences follow:

  1. The rate is your loan rate. If your mortgage is 6.00%, each offset dollar earns the equivalent of 6.00%. If it falls to 5.50%, so does your offset benefit.
  2. No tax applies. You are not earning interest, you are avoiding it. The ATO’s long-standing ruling on loan account offset arrangements is the basis for this treatment of home loans. Your lender does not report anything to the ATO for offset savings.
  3. You keep access. An offset is a transaction account. You can spend from it, receive your pay into it and withdraw whenever you like. Moneysmart notes this flexibility in its guidance on paying off your mortgage faster.

The tax maths, with a worked example

Here is a simple comparison. The numbers are illustrative assumptions, not a quote from any lender.

Offset account Savings account at 4.55% Savings account at 6.00% bonus rate
Gross annual benefit $3,000 $2,275 $3,000
Tax at 32% $0 $728 $960
After-tax benefit $3,000 $1,547 $2,040

Even a savings account paying the same headline rate as your mortgage loses roughly a third of its value to tax in this example. At 4.55% it falls well short.

The break-even rate

To find the savings rate that matches your offset, divide your loan rate by one minus your marginal rate.

  • At 6.00% loan rate and 32% marginal rate: 6.00 ÷ 0.68 = 8.82%.
  • At a 37% bracket (39% with Medicare): 6.00 ÷ 0.61 = 9.84%.
  • At a 16% bracket (18% with Medicare): 6.00 ÷ 0.82 = 7.32%.

No mainstream savings account pays those rates. The highest rates currently advertised top out around 6.00% p.a. and only if you meet every monthly condition. So for a borrower with a variable-rate loan and a working offset, the offset wins on the numbers in nearly every case.

The gap widens for higher earners and narrows for people on low incomes. Someone on a very low taxable income, such as a retiree under the tax-free thresholds, pays little or no tax on savings interest. For them the comparison is closer, though an offset still saves interest at the loan rate with no conditions.

Why bonus savings rates are not what they seem

Headline savings rates are often built from a base rate plus a bonus. Canstar’s savings account comparison shows accounts where the bonus depends on growing your balance by a set amount, such as $100 a calendar month, excluding interest, or where the bonus applies only for an introductory period. The October 2026 rate table at Bankmate reports that 108 of 153 tracked accounts ask something of you each month or carry an age limit.

That matters for two reasons. First, the bonus disappears the month you withdraw money or fail to deposit. Second, a rate that looks close to your mortgage rate becomes a poor comparison once tax comes off. An offset has no conditions: every dollar works at the loan rate every day.

Rates also move. The big banks reprice after Reserve Bank decisions, and CommBank, for instance, announced savings rate changes effective 9 October 2026. Check your lender’s current rates before you decide, and rerun the numbers each time your loan rate changes.

When a savings account is the better choice

An offset is not always the right home for your cash. A savings account makes more sense when:

  • You have no home loan, or you are on a fixed rate. Offset benefits only apply while the linked loan is variable with many lenders, and Moneysmart notes offsets are generally attached to variable loans. If your loan is fixed with no offset, the cash has nowhere to offset against.
  • Your offset balance would stay small. Moneysmart’s guidance is that an offset only pays if your balance is meaningful enough to justify any extra cost. If you would hold under about $10,000 and the package costs more, the saving may not cover the premium.
  • The offset loan carries a higher rate or annual fee. Loans with more features can come at a higher cost. A basic no-frills loan with a lower rate may beat a package loan with an offset, especially for small balances.
  • You want a deliberate separation. Some people prefer their emergency fund or a holiday fund to sit out of sight, where they will not spend it. A separate savings account can serve that purpose, though you can also open several offset accounts with some lenders. Check how many your lender allows.
  • Your loan is nearly paid off. When the balance is small, there is little interest left to offset.

The hidden cost: the rate premium

The offset itself is free or cheap. The loan that comes with it is where the cost can hide. Moneysmart’s guidance on offset accounts says to compare monthly or annual fees against the value of interest saved, and loans with an offset can carry higher rates than basic loans.

A quick test: take the extra interest you pay on the offset loan compared to the no-frills alternative, then compare it to the interest the offset saves.

Example: your offset loan costs 0.20 percentage points more on a $600,000 balance, which is $1,200 a year. Average offset balance is $30,000 at 6.00%, saving $1,800. Net benefit: $600 a year, before any annual package fee. If your average balance were $15,000, the saving would be $900 and the net benefit would be negative once a package fee of $395 is included.

Offset savings compared with loan costs and fees

This is why average daily balance matters more than the balance on the day you open the account. Interest is calculated daily on the net balance, so money that sits there between paydays counts, and so does a pay deposit that stays for a few days before bills go out.

Offset versus redraw is a different question

Many borrowers confuse an offset with a redraw facility. With redraw you pay extra into the loan, and later withdraw it, if your lender permits. With an offset, your money stays outside the loan. For a home you live in, that distinction is mostly about convenience and fees. For an investment property, it can change your tax position. Our guide on offset versus redraw covers it in detail.

Investment property: the deduction trade-off

If the loan is for an investment property, interest is generally deductible. That changes the maths. Money in an offset reduces the interest you pay, which also reduces the deduction. You still come out ahead in cash terms: saving $1 of non-deductible-equivalent interest is better than paying $1 of interest and getting back your marginal rate on it. But the saving is smaller after tax than the headline loan rate suggests.

A few points to keep straight:

  • Interest saved on an investment loan reduces your deductible expense, so compare after-tax outcomes, not just loan rates.
  • Withdrawing cash from an offset linked to an investment loan and using it for personal purposes does not change the purpose of the original borrowing, but withdrawing it to buy something else can matter for other loans. The ATO has published guidance on interest deductions after withdrawing from an offset account to buy shares.
  • Where your own home loan and investment loan both exist, the usual planning approach is to put spare cash against the loan that is not deductible, which is your home loan. Confirm this with a registered tax agent for your situation.

For property investors weighing yield, rates and cash flow together, this rental yield and ATO rules guide for Australian buyers gives useful context on the figures behind a purchase. For the offset mechanics specifically, see our offset account for investment property guide and the overview of investment property tax deductions.

Offset vs savings in retirement

For retirees and people planning an early exit from work, the comparison has an extra dimension: access and income.

An offset account gives you immediate access to your capital, without the withdrawal limits or bonus conditions that apply to some savings products. That makes it a handy place to hold a cash buffer while you still have a mortgage. It can reduce the interest you pay at a time when your pay has stopped. Because the benefit is not income, it also does not add to your assessable income. Savings interest does, and the ATO notes that interest must be included in your tax return. If you do not give your bank your Tax File Number, tax is withheld at the highest marginal rate.

Offset vs savings in retirement — overview diagram

Two cautions for people near retirement. First, if the mortgage will be cleared soon, whether from a lump sum or super, the offset’s benefit ends with the loan, so work out whether the cash is better kept in the offset until payout or moved elsewhere. Second, if you are retiring before preservation age, you may need a bridge of accessible money. Cash in an offset is accessible, but decide how much you can leave there without starving your bridge. For a deeper look, see our mortgage offset calculator guide for retirement.

A five-step way to decide

  1. Write down your loan rate and whether it is variable or fixed. If there is no offset on the loan, the choice is moot unless you refinance.
  2. Estimate your average daily balance. Use the last three months of statements, not your best day.
  3. Find your marginal tax rate including Medicare. Your payslip or last tax assessment shows your taxable income.
  4. Compute the break-even savings rate. Loan rate ÷ (1 minus marginal rate). Compare with the best savings rate you can sustain without conditions.
  5. Subtract the offset premium. Include any rate difference and annual package fee against a plain loan.

If the offset still wins after step 5, link your pay to it and keep only your bills buffer elsewhere.

Our perspective

We built Aerowealth because this question rarely has a one-line answer. The rule of thumb is sound: for most borrowers with a variable loan, offset beats savings after tax. But the size of the gap depends on four things that change over time: your loan rate, your marginal rate, your average balance and whether you are still working.

A single spreadsheet cell does not capture that. What we see in planning is that people compare today’s rates and ignore the long run. A $40,000 balance that sits in an offset for the next 12 years is worth far more to your retirement date than the same money earning taxable interest. The difference can move your mortgage-free date by months or years, and that shifts when you can stop working or draw on super.

That is why we model it as a scenario, not a calculation. You can set up one plan where cash sits in an offset and another where it sits in a savings account, then compare them side by side on retirement age, income and net worth. You can also stress test them: what happens if rates rise by two percentage points, or fall? Does your answer change if your income drops at 55?

Our view is simple. Use the quick break-even rule above to make a first decision. Then test it against the rest of your plan, because the real value of an offset shows up over decades.

— Aerowealth Team

Model your own numbers

The free plan on Aerowealth lets you start modelling your mortgage, super and investments in one place. If you want bridge-years modelling for early retirement, advanced mortgage features or a higher AI assistant quota, Pro is 7 AUD per month. See the plans and pricing, or start from the Aerowealth home page.

FAQ

Is an offset account better than a high-interest savings account?

Usually yes, if you have a variable-rate loan with an offset and a reasonable balance. Offset savings are measured at your loan rate and are not taxed, while savings interest is taxed at your marginal rate. A savings account only wins when your loan has no offset, the loan is fixed, or the offset package costs more than it saves.

Do I pay tax on the money I save with an offset account?

No. An offset reduces interest you would otherwise pay, so nothing is earned or derived, as Moneysmart explains. The exception to watch is an investment loan, where lower interest also means a smaller deduction.

How much do I need in an offset for it to be worth it?

There is no single threshold. It depends on the extra rate or fees you pay for the offset loan. Moneysmart’s guidance points to balances under about $10,000 as the zone where the saving may not justify a premium. Compare your annual interest saved against the annual cost.

Is an offset account the same as a redraw facility?

No. Redraw means paying extra into the loan and withdrawing it later, if your lender allows. An offset keeps your money in a separate account linked to the loan. Our offset vs redraw comparison explains how the two differ in access, fees and tax.

Sources

← Back to blog