How to Dispute an illion Default in Australia (Now Experian): Step-by-Step Guide

Quick Answer: illion is now part of Experian. Experian completed its acquisition of illion on 30 September 2024, and from 1 April 2026 the two operate as a single Experian credit reporting body, so a default that was on your illion file now appears on your Experian credit report. To dispute it, get your free Experian report, then lodge a dispute with Experian (and/or the credit provider that listed it). Under the Privacy (Credit Reporting) Code 2025, the credit reporting body must investigate within 30 days and correct the listing if it was recorded incorrectly. If the default is retained, you can escalate to external dispute resolution or the OAIC, or seek professional legal assistance under the Privacy Act 1988.

You've found a default that was listed on your illion credit file — or your lender has told you it saw a default on your "illion" report — and you don't recognise it, or you suspect it was listed without following the correct process. Maybe the amount is wrong, you never received notice before it appeared, or the debt was settled before the listing date. Whatever the case, you have the right to dispute it.

illion — formerly Dun & Bradstreet Australia — used to be a separate credit bureau. It is now part of Experian, and Experian says you now receive one credit report that includes all the information previously held by illion and Experian. Australia's credit reporting bodies are now Equifax and Experian. Defaults stay on your credit report for five years from the date they're listed. But if a default was recorded incorrectly or in breach of the rules under the Privacy Act 1988, the law requires it to be corrected.

Here is how to dispute a default that started on your illion file, what the law requires, and when a professional review of the file makes the difference.

What Happened to illion, and Where Is Your Default Now?

Experian completed its A$820 million acquisition of illion on 30 September 2024. From 1 April 2026, illion and Experian operate as a single Experian credit reporting body (CreditSmart, the consumer site of the Australian Retail Credit Association). The information previously held on your illion file, including any default, is now part of your Experian credit report.

CreditSmart notes that lenders may take some time to update their letters, so a reference to "illion" in something your lender sends you generally refers to the combined Experian report.

Under the Privacy (Credit Reporting) Code 2025, which commenced 25 March 2025, credit reporting bodies have strict obligations: they must only hold information that is accurate, up to date, and was reported by the creditor in compliance with the required process. If a creditor failed to follow the correct steps before listing, the listing is invalid and can be challenged.

Your Experian report is separate from your Equifax file. A default may appear on one or both — and each needs to be disputed independently. Understanding how credit files work across the two bureaus helps you know exactly where the listing sits.

When Is a Former illion Default Legally Challengeable?

A default that started on your illion file is challengeable where the listing breached the required process under the Privacy Act 1988, Part IIIA, or the Privacy (Credit Reporting) Code 2025. Four grounds account for most successfully removed listings:

A fifth ground covers identity errors — defaults listed in your name for a debt belonging to someone else, including identity fraud. If none of these apply, and the creditor followed every step correctly, the listing cannot be removed before the five-year retention period ends. Being honest about that is part of how we work. For a full breakdown, see what are valid grounds to dispute a default in Australia.

How to Get Your Credit Report (Formerly Your illion File)

Before you can dispute, you need the report in front of you. Request your free Experian credit report at experian.com.au/consumer/order-credit-report. It includes the information previously held by illion. You're entitled to it free every 3 months, and also free if you've been refused credit in the past 90 days or had information corrected.

To access your report:

1. Go to experian.com.au/consumer/order-credit-report
2. Verify your identity
3. View and save your report

Review every listing carefully — the creditor name, the listed amount, and the date. Screenshot or download the default entry before you begin the dispute process. It's also worth getting your Equifax report, because the same default may appear there too.

How to Lodge a Formal Dispute

Once you've identified the error, you can ask Experian to correct the information, or raise it with the credit provider that listed the default. The process is free. You don't need to pay a third party to submit a dispute on your behalf.

Step by step:

1. Use Experian's correction process (via experian.com.au), or write to the credit provider that listed the default
2. Describe the specific error in writing — be precise: "The listed amount is $X; the correct outstanding amount was $Y at the time of listing" or "I did not receive a Section 21D pre-listing notice at my address before this default appeared"
3. Attach supporting evidence — bank statements showing payment, proof of your correct address at the relevant time, correspondence with the creditor, any notice you received (or evidence you didn't receive one)
4. Submit the dispute
5. Keep a copy including the date lodged — you'll need this if you escalate

If you have questions about a report that used to be your illion file, the Experian contact for Experian and illion credit report enquiries is 1300 784 134.

How Long Does an Investigation Take?

Under the Privacy (Credit Reporting) Code 2025, which commenced 25 March 2025, the credit reporting body must complete its investigation within 30 days of receiving your correction request. This is a legal obligation — not a service target.

During that window, the bureau contacts the credit provider (the creditor that reported the default) and asks it to verify the accuracy of the listing. If the creditor cannot substantiate the listing, the bureau is required to correct it.

At the end of the investigation, you're notified in writing of the outcome: whether the listing has been corrected, removed, or retained as originally recorded.

What Happens If the Default Isn't Removed?

If the investigation concludes with the default retained, and you still believe it was listed incorrectly, two further paths remain.

Ask for a statement to be associated with the listing. A note recording your position doesn't remove the default, but it puts your version of events on record.

Escalate to external dispute resolution or the OAIC. Under the Privacy Act 1988, you have the right to escalate an unresolved complaint to external dispute resolution. The OAIC (Office of the Australian Information Commissioner) can also investigate a potential breach of the Privacy Act where the bureau or the creditor failed to meet their obligations — see how to escalate a default dispute to the OAIC in Australia for the step-by-step process.

If the default relates to a debt you're still struggling with, the National Debt Helpline on 1800 007 007 offers free financial counselling — independently of any credit repair process.

If the creditor itself is the source of the breach — for example, it listed the default without a valid Section 21D notice — the dispute is really a challenge of the creditor's conduct. That's where the investigation often needs to go deeper than a standard bureau form.

When a Lawyer-Led Dispute Gets Further

A bureau investigation relies on what the creditor reports back. If a creditor responds and says "the listing is correct," the bureau will typically retain it — even where the underlying listing process was technically flawed. That's a question of legal leverage.

Australian Credit Solutions holds Australian Credit Licence ACL 532003 and operates under the Privacy Act 1988. Our solicitor reviews the original creditor file — the Section 21D notice itself, the dispatch address, the listed date, the amount recorded — against the legal requirements of Part IIIA and the Privacy (Credit Reporting) Code 2025. Where a breach is found, a formal legal submission to the creditor and the bureau carries different weight to a self-lodged consumer dispute.

If you've already submitted a dispute (with illion before the merger, or with Experian since) and it was rejected, that doesn't close the matter. It means the evidence on the table at the time wasn't sufficient. Our default removal services involve reviewing the original submission and rebuilding the case before re-engaging.

Frequently Asked Questions

Can I still dispute an illion default? Yes. illion is now part of Experian, so a default that was on your illion file now appears on your Experian credit report. You can ask Experian to correct it, or raise it with the credit provider that listed it. Disputing is free, and the credit reporting body must investigate within 30 days under the Privacy (Credit Reporting) Code 2025.

Can I dispute a former illion default for free in Australia? Yes — disputing is entirely free. Credit reporting bodies are required by the Privacy Act 1988 (Cth) to provide a correction process at no cost to consumers. No paid intermediary is required to submit the initial dispute.

How long does an investigation take? The credit reporting body must complete its investigation within 30 days of receiving your request under the Privacy (Credit Reporting) Code 2025. In straightforward cases the outcome may come sooner. If you don't receive a response within that window, contact the OAIC.

What are valid grounds to dispute a default that was on my illion file? The most common valid grounds under the Privacy Act 1988 are: the creditor did not send a valid Section 21D pre-listing notice; the listed amount is incorrect; the default was listed before the debt was 60 days overdue; the debt was paid before the listing date; or the listing belongs to someone else. For the full breakdown, see our guide on valid grounds to dispute a default in Australia.

Does disputing a default affect my credit score? Lodging a dispute does not itself reduce your credit score. If the dispute succeeds and the listing is removed or corrected, your score may improve, but that depends on the rest of your file.

What if the bureau says the default is correct but I still believe it was listed unfairly? You can: (1) ask for a statement recording your position; (2) escalate to external dispute resolution or the OAIC under the Privacy Act 1988; or (3) seek a professional legal review of the original listing — a rejected self-dispute doesn't preclude a lawyer-led challenge if a technical breach in the creditor's process exists.

How is disputing a former illion default different from disputing with Equifax or Experian? It isn't a separate process any more. Both credit reporting bodies — Equifax and Experian (illion is now part of Experian) — operate under the same Privacy Act 1988 framework and the Privacy (Credit Reporting) Code 2025. A former illion default is now on your Experian report, so you dispute it through Experian or the credit provider. If the same default also appears on Equifax, dispute it there too. Compare the process with how to dispute an Equifax default and how to dispute an Experian default.

What evidence do I need? The evidence needed depends on the grounds. For a Section 21D notice challenge: proof of your correct address and any change-of-address notifications to the creditor. For an amount dispute: bank statements and the original account balance showing the correct figure. For a paid-debt dispute: payment receipts, bank transactions, or a settlement confirmation showing the debt was cleared before the listing date. Specific, documentary evidence is what causes a creditor to concede.

What was illion formerly known as? illion was formerly known as Dun & Bradstreet (Australia). It is now part of Experian: Experian completed its acquisition in September 2024, and from 1 April 2026 illion and Experian operate as a single Experian credit reporting body.

How do I know if my default is on Experian or Equifax? Get your free credit report from each bureau separately: Experian at experian.com.au/consumer/order-credit-report (which includes the former illion information) and Equifax at equifax.com.au. A default may appear on one or both, depending on which bureau the creditor reported to. A dispute with one bureau has no effect on a listing of the same debt at the other.

What to Do Next

If you've found a default that started on your illion file, the first step is to determine whether it was listed correctly. Get your Experian and Equifax reports, review the listing against the Section 21D notice rules under the Privacy Act 1988 and the Privacy (Credit Reporting) Code 2025, and gather your evidence.

If you believe a breach occurred, lodge a dispute with Experian or the credit provider directly — it's free. If the dispute is rejected or the matter requires a closer legal review, Australian Credit Solutions can assess the full picture.

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Australian Credit Solutions Pty Ltd holds Australian Credit Licence ACL 532003. Credit repair services are subject to individual assessment. Results may vary. This article provides general information only and does not constitute legal or financial advice.

Sources: Experian plc, "Experian completes A$820m acquisition of illion" (1 October 2024); CreditSmart (ARCA), "Changes to the Experian and illion credit reporting bodies"; Experian Australia, "Order your free credit report"; OAIC, "Access your credit report".

Related reading: How to Dispute an Equifax Default → | How to Dispute an Experian Default → | Valid Grounds to Dispute a Default →