Tax Mistake Discovered: Correct It Now or Wait for an Audit?

Discovering a tax mistake can be stressful. Whether it involves omitted rental income, undeclared business income or an error in a previously filed tax return, one question usually follows: should the taxpayer make a voluntary disclosure to LHDN now, or wait until the matter is discovered during a tax audit?

The answer depends on the amount, the years involved, the records, and whether LHDN has already started looking.

What Most Taxpayers Get Wrong

Many taxpayers assume the moment they find an error, they should write to LHDN immediately. That is usually not the right first step.

There are three distinct correction routes, and they are not interchangeable:

• Amended return under s.77B ITA 1967 — generally available within six months of the original filing due date. Corrects an assessment within the statutory window.
• Voluntary disclosure before audit action — used when the s.77B window has closed, or when the correction spans multiple years. The taxpayer initiates before LHDN has opened any file.
• Response after LHDN has commenced action — once LHDN has issued an audit notice, information request or any other form of contact, neither of the above applies cleanly. The taxpayer is responding to LHDN, not initiating.

A landlord with three years of unreported rental income cannot correct all three years with a single amended Form BE. That is the fork many taxpayers miss.

In our files, once an audit has started the conversation is about explaining non-compliance that LHDN has already found. Before that, there is time to establish the years, the tax, and the explanation.

Common Tax Errors We See

The situations that lead to this conversation vary. Some of the more common ones:

• Rental income not reported for one or more years
• Commission or freelance income omitted from personal tax returns
• Deductions claimed without supporting documentation
• Historical accounting errors carried forward across multiple years
• Business income understated due to a misunderstanding of what is taxable

These are not always deliberate. In many cases, the taxpayer did not know the income was taxable, received incorrect earlier advice, or inherited a filing position from a previous accountant. The reason an error occurred is important. But once the taxpayer becomes aware of it, the focus shifts to how it should be corrected.

How We Evaluate a Tax Error Before Any Disclosure

When a client comes to us with a potential tax error, we work through a structured assessment before any decision is made:

On penalty: voluntary disclosure before audit action is generally treated more lightly than an error found during audit. In practice, the rate LHDN commonly applies to voluntary disclosure before audit action is 15%, compared to 45% during audit procedures and 60% or higher during investigation. Under the Tax Audit Framework, penalties also step up with the number of prior offences and with whether the omission is found to be deliberate. Wilful cases sit in a different category entirely. The actual rate in any individual case remains LHDN’s assessment on the facts — we do not quote a number until we have reviewed the file.

Three Scenarios We Handle Regularly

A Situation We Encounter Regularly

One situation we handle regularly involves rental income omitted over multiple years. The taxpayer owns a property, collects rental, but did not report it — sometimes because they were unaware it was taxable, sometimes because the omission was not corrected in subsequent years after it started.

Rental income is an area where many taxpayers still underestimate the risk of detection. Tenancy agreements, stamp duty records, bank transactions and other data sources increasingly allow information to be cross-checked against tax returns. Errors that may have gone unnoticed years ago are becoming easier for LHDN to identify.

In cases like these, we work through the full assessment above before any approach to LHDN. We quantify the shortfall across all affected years, review what rental documentation is available, assess the applicable penalty provisions, and prepare a complete explanation of the circumstances.

In one recent case of this nature, the taxpayer decided to regularise the position before any enforcement action commenced. The eventual outcome reflected factors including the voluntary nature of the disclosure, the taxpayer’s cooperation, the quality of supporting documentation, and the specific circumstances of the case. We prepare the file so LHDN can assess it on the facts.

Why Professional Representation Changes Outcomes

At the same National Tax Conference 2026, LHDN shared a case study that illustrated this point. Two companies faced penalty issues. One appealed directly, without professional assistance. The other engaged a tax agent to manage the appeal. The outcomes differed — despite the underlying issues being of similar nature.

This was not presented as a guarantee. It was an illustration of what professional representation typically brings:

• Facts presented clearly and in the right sequence
• Commercial background and business circumstances explained in context
• Relevant tax provisions and LHDN guidelines cited correctly
• Supporting documents organised and complete before submission
• Communication with LHDN officers in appropriate technical language

LHDN officers deal with a high volume of cases. A well-prepared, clearly explained submission allows the officer to understand the facts more quickly and assess the matter on its merits.

The Cost of Waiting

LHDN’s visibility into taxpayer income is increasing. Under the MITRS framework (s.82B, Income Tax Act 1967), tax agents now submit supporting documents directly to LHDN alongside Form C. Rental income, commission receipts and bank credits that appear in those documents but not in the tax return are easier to identify than they were before. We discussed how this affects income tax exposure in our earlier articles on MITRS and LHDN financial disclosure under s.82B and how MITRS increases tax risk visibility in Malaysia.

When LHDN initiates an audit and finds an error the taxpayer already knew about, the conversation starts from a different place. The penalty discussion usually starts higher, and the file is no longer treated as a voluntary regularisation. The relationship with LHDN — which matters across future filings, audit risk, and any subsequent dealings — is harder to rebuild from an enforcement encounter than from a cooperative disclosure.

If the error is real and LHDN has not opened the file, the usual better sequence is: understand it, quantify it, then decide how to regularise.

Frequently Asked Questions

What is voluntary disclosure to LHDN?

Voluntary disclosure is when a taxpayer approaches LHDN on their own initiative to report omitted income or correct a filing error — before LHDN has commenced any audit or investigation. The taxpayer initiates, not LHDN. It is separate from any government-run special voluntary disclosure programme (SVDP).

Does voluntary disclosure guarantee a penalty waiver?

No. Penalty remains LHDN’s discretion. What voluntary disclosure generally does is position the file differently from one where LHDN found the error during audit. The penalty discussion usually starts from a lower base when the taxpayer comes forward first and the disclosure is supported by complete records and a clear explanation.

What is the difference between a voluntary disclosure and an amended return under s.77B?

An amended return under s.77B ITA 1967 is generally available within six months of the original filing due date. A voluntary disclosure before audit action is a separate route used when the s.77B window has closed or when the correction involves multiple years. Once LHDN has opened the file, neither applies cleanly.

What happens if LHDN finds the error before the taxpayer discloses?

Once LHDN has opened the file — through an audit notice, an information request or any other contact — it is no longer a clean voluntary disclosure. The file is treated as an audit finding. Penalties under the Tax Audit Framework step up based on the number of prior offences and whether the omission is found to be deliberate.

How does LHDN detect undeclared rental income?

Tenancy agreements, stamp duty records, bank transactions and data submitted under the MITRS framework (s.82B ITA 1967) allow LHDN to cross-check declared income against third-party sources. Rental income that appears in supporting documents but not in a tax return is becoming easier to identify.

Should I approach LHDN directly or engage a tax agent?

At the National Tax Conference 2026, LHDN shared a case study involving two companies with similar penalty issues. One appealed directly. The other engaged a tax agent. The outcomes differed. Professional representation affects how facts are presented, how commercial background is explained, and how documents are organised before submission.

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