Structuring Splits, Offsets and Redraw To Protect Tax-Deductible Debt

For Australian borrowers using debt recycling or gearing, the safest way to track deductible vs non‑deductible debt is: 1) separate loan splits by purpose (home, investment, business), 2) park surplus cash in an offset against the non‑deductible home split, and 3) avoid using redraw for mixed purposes. That combination keeps interest deductibility clear under ATO tracing rules and flexible as tax laws change.

Why tracking deductible vs non‑deductible debt is non‑negotiable now

Negative gearing and investment tax rules are tightening from 1 July 2027, especially for established properties bought after 12 May 2026. The ATO already focuses on purpose and tracing – what you borrowed for, and where repayments came from.

If you mix home and investment spending in one loan or redraw, you risk:

1. Losing interest deductions on the investment portion.
2. Facing messy, expensive accountant work every year.
3. Being stuck if you later want to refinance or sell just one asset.

Clean splits and smart use of offsets and redraw are now more important than squeezing an extra 0.20% off the rate.

Separate loan splits by purpose to keep deductible and non-deductible interest clear.

Core tools: splits, offsets and redraw – what they actually do

Loan splits – one facility, multiple clear purposes

A loan split is simply carving your total mortgage into separate accounts inside the one home loan contract – for example:

• Split A – $700,000 – home (non‑deductible)
• Split B – $200,000 – investment (deductible)
• Split C – $80,000 – business equipment (potentially deductible)

Each split has its own balance, repayment and sometimes different rate/term.

Key benefits:

• Clear tax tracing by purpose.
• Ability to pay down non‑deductible debt faster.
• Option to fix, refinance or close one split without disturbing the others.

This aligns with a core principle we use across guides like How to Restructure Property Loans Before Negative Gearing Shrinks: separate by purpose, not by property.

Offset accounts – cash parked beside the loan

An offset account is a transaction account linked to a loan split. The balance reduces interest charged, but does not reduce the legal loan balance.

Best practice for debt recycling:

• Link your main offset to the non‑deductible home split.
• Keep investment and business cash in separate offsets, not mixed with personal spending, as we discuss in Smartly coordinating home, investment and business loans across East and Inner South.

Redraw – money you’ve already repaid

Redraw lets you take back extra repayments made on a loan split. The tax danger is that every redraw changes the purpose of that part of the loan.

Use redraw cautiously:

• If you redraw from a home (non‑deductible) split to invest, that portion can become deductible.
• If you later redraw from the same split for a holiday, you have a mixed‑purpose loan that’s hard to trace.

The ATO guidance is clear: interest is deductible only to the extent the current use of the borrowed funds is income‑producing.

Offset vs redraw vs extra repayment: which to use when?

A general rule: offset preserves options; redraw rewrites history.

Worked example: clean vs messy debt recycling structure

Scenario

• Home value: $1.4m
• Existing home loan: $900,000 (one large split)
• Goal: start a simple debt recycling plan investing $200,000 into ETFs.

Messy approach – one big loan and redraw

1. You aggressively repay $200,000 into the single home loan.
2. You then redraw $200,000 and invest it.
3. A year later, you redraw another $50,000 for a car.

Result:

• You now have one $750,000 loan with two purposes: $200,000 investment, $50,000 car, the rest home.
• Every future repayment has to be split across three purposes to work out deductible interest.
• If you refinance or sell, tracing becomes a nightmare.

Cleaner approach – using splits and offsets

Instead, you restructure first (often as outlined in How to Refinance and Quarantine Deductible vs Non‑Deductible Debt Now):

1. Refinance into:
   • Split A – $700,000 – home (non‑deductible), with main offset.
   • Split B – $200,000 – investment (to be used for ETFs).
2. Park surplus cash in the offset linked to Split A.
3. Draw the $200,000 for ETFs from Split B only.

Now:

• Split A is always non‑deductible. You aim to drive this down with surplus cash.
• Split B is 100% investment purpose. All interest is potentially deductible while the investment is held.
• There is no redraw spaghetti. If you later need a car, you set up Split C – car/personal and keep it clearly non‑deductible.

Indicative numbers (P&I 25 years, 6.5% p.a., rounded):

• Split A – $700,000 → repayment ≈ $4,730/month.
• Split B – $200,000 → repayment ≈ $1,350/month.

Directing an extra $1,000/month via offset against Split A could save tens of thousands in non‑deductible interest over 10–15 years while leaving your deductible Split B intact.

Offsets preserve flexibility while redraw can create mixed-purpose, hard-to-trace debt.

Practical rules for using splits, offsets and redraw safely

1. One purpose per split

Where possible, each split should fund one clear purpose:

• Home to live in.
• Single investment property deposit and costs.
• Portfolio of shares/ETFs.
• Business equipment or working capital.

This mirrors the principles we use when consolidating debts in How To Consolidate Debts With Home Equity Without Restarting 30 Years.

2. Direct cash to non‑deductible debt first

In a higher‑rate world, and with negative gearing benefits shrinking for some properties, the priority order for most households is:

1. Build a modest cash buffer in the home offset (e.g. 3–6 months’ expenses).
2. Smash down the non‑deductible home split using offset + extra repayments.
3. Only then consider accelerating deductible investment splits.

Remember APRA’s 3% serviceability buffer – every extra dollar of non‑deductible debt you clear improves your borrowing flexibility.

3. Keep business and personal separate

If you’re self‑employed or a small business owner:

• Use separate splits and offsets for business purposes.
• Never treat your home loan redraw as a revolving overdraft.

This keeps both your ATO records and your bank’s credit view cleaner – a theme we expand on in How Small Business Owners Can Use Offset and Redraw Accounts Safely.

4. Redraw only from the right split, for the right use

If you must use redraw:

• Only redraw from a split whose purpose matches the withdrawal.
• Avoid reusing an investment split for private spending later.
• If you change purposes, consider setting up a new split, not reusing the old one.

Document every redraw: date, amount, purpose and supporting evidence.

One‑week action plan to clean up your structure

Day 1–2 – Map your current loans

• List each facility, balance, rate and what it actually funded.
• Highlight any loans or redraws with mixed purposes.

Day 3–4 – Design the target structure

• Decide the minimum set of splits: home, each investment, any business or consolidated debts.
• Choose which splits get offsets and which can stay simple.

Day 5 – Talk to your broker and accountant together

• Sense‑check deductibility under current ATO rules.
• Stress‑test under 2026–27 negative gearing changes (especially if buying established property).

Day 6–7 – Implement changes

• Request internal splits or a refinance into the new structure.
• Redirect salary and surplus cash into the home offset only.
• Stop using redraw for mixed spending.

FAQs

How do I know if my interest is tax‑deductible?

Interest is generally deductible where the borrowed funds are used to earn assessable income (for example, rent or business income). The ATO looks at how each dollar was used, not which property secures the loan. Keeping separate splits and clear records of drawdowns, repayments and redraws makes this tracing far easier and reduces the risk of deductions being denied.

Is an offset better than redraw for debt recycling?

For most debt recycling strategies, an offset linked to the non‑deductible home split is safer than heavy use of redraw. The offset reduces interest without changing the legal loan balance or its purpose, so you keep future deductibility options intact. Redraw, by contrast, changes the purpose of part of the loan each time you use it, which can quickly create mixed‑purpose, hard‑to‑trace debt.

Can I fix the rate on my investment split only?

Often yes, subject to lender policy. Many borrowers fix the investment split to give cashflow certainty while keeping the home split on variable with an offset for flexibility. Just remember that fixing can restrict extra repayments or access to offset, so match your choice to your 3–5 year plans and check break‑cost rules before locking in.

What if I’ve already mixed home and investment spending in one loan?

You may not be able to fully “unmix” it, but you can usually stop it getting worse. First, stop using redraw for new mixed purposes. Then, talk to your broker and accountant about refinancing into new splits that reflect the current balances by purpose. From there, direct extra repayments to the non‑deductible portions and keep new investment borrowing quarantined.

How often should I review my splits and offsets?

At least annually, and also when big life events happen – new property, renovations, major investments, business changes, or upcoming tax reforms. A short yearly check‑in lets you adjust splits, move offsets, and confirm that actual cashflows still match the tax story you and your accountant are relying on.

Key takeaways

• Use one clear purpose per split to keep deductible vs non‑deductible interest easy to trace.
• Park buffers and surplus cash in an offset linked to your non‑deductible home split, not in redraw.
• Avoid mixed‑purpose redraws; if you change purpose, create a new split instead.
• Review your structure before the 2026–27 negative gearing changes so your debt recycling plan stays ATO‑proof.

Next step: Want a 30‑minute structure check across your home, investment and business loans? Book a free strategy session at /book – one conversation covers your tax, your loans and your next moves with a CPA, Tax Agent and Broker in one.

General advice only.