Form C Malaysia: The Ultimate Guide for LHDN Tax Filing

Form C must be filed within 7 months of your Financial Year End and requires reconciling your audited revenue with e-invoice data and submitting technical documents via the MITRS portal within 30 days post-filing.

In the old days, you could scramble at the 11th hour, but e-Invoicing and MITRS mean the “anyhow-fill” method is a one-way ticket to a desk audit. The truth is this, if your revenue figures don’t match your e-invoice trail, that RM20,000 penalty is an automated invoice waiting to happen.

Today, our accounting services guide will break down the updated 2026 filing calendar, the technical nuances of the new MITRS requirements, and how to protect your SME’s 15% tax rate in an era of total transparency.

Form C Quick Comparison (YA 2025/2026)

Before all else, use this table to ensure you are filing the correct form for your entity type.

Filing Deadlines: The 7-Month Rule

The deadline for Form C is relative to your Financial Year End (FYE). Missing this window results in an immediate 10% surcharge on tax payable.

“The e-filing grace period is a lifeline, but the MyTax portal often experiences heavy traffic on the final day of the month. Aim to submit at least 72 hours before the deadline to avoid system timeouts.” — Mrs Lim, Senior Accountant from Accounting.my

What is MITRS and Why Is It Mandatory?

Under Section 82B of the Income Tax Act, you are now required to “show your work” digitally. The MITRS is the portal where these documents live.

The 30-day window for MITRS is calculated from your statutory due date, not your actual submission date.

• Audited Financial Statements: Must include the Directors’ Report and detailed P&L.
• Tax Computation: A step-by-step breakdown of how accounting profit became taxable income.
• Capital Allowance Schedules: Detailed lists of assets (laptops, machinery) and their depreciation rates.

For example, if your FYE is 31 Dec 2025, your e-filing deadline is 31 August 2026. Your MITRS documents must be uploaded by 30 September 2026, even if you submitted your Form C early in July. 

Failing to upload these PDFs (max 20MB) triggers an automatic non-compliance flag in LHDN’s system, this is different from form CP204 which we have a whole guide on.

SME Tax Rates: Protecting Your 15% Tier

In Malaysia, qualifying as a SME gives you significant financial advantages.The difference between the SME rate and the standard corporate rate can save a business up to RM45,000 in taxes annually.

The Three-Tiered SME Tax Scale

If your company qualifies, your taxable income is calculated using a “staircase” model rather than a flat fee:

The “Golden Rules” of SME Eligibility

To claim these lower rates, LHDN enforces strict “anti-fragmentation” rules to prevent large corporations from spinning off smaller units just for tax breaks. 

Your Sdn Bhd must meet these three criteria at the start of the basis period:

• Paid-up Capital: Must be RM2.5 million or less.
• Gross Business Income: Total turnover from all business sources must not exceed RM50 million.
• The Ownership Clause: The company cannot be part of a group where a related company (with >50% shareholding) has a paid-up capital exceeding RM2.5 million. Additionally, no more than 20% of the paid-up capital can be owned by foreign companies or non-Malaysian citizens.

Scenario: Consider two companies with RM500,000 in profit.

• Standard Company: Pays a flat 24% = RM120,000.
• Qualifying SME: (15% of 150k) + (17% of 350k) = RM82,000.

The Result: The SME saves RM38,000,capital that can be reinvested into hiring or scaling operations.

“According to LHDN’s 2025 enforcement data, over 1,000 companies were flagged for additional tax assessments totaling RM15.2 billion. A significant portion of these adjustments came from companies wrongly claiming SME status despite being part of a larger corporate group.”

e-Invoicing: The New Audit Frontier

By July 1, 2026, every business in Malaysia must be fully operational on the e-Invoicing system. 

For your Form C submission, this creates a “Data Mirror” effect: LHDN now sees your sales data in real-time, leaving no room for manual “adjustments” at year-end.

Mandatory Individual e-Invoices (The RM10k Rule)

While LHDN allows consolidated e-invoices (grouping multiple small receipts into one monthly submission) for many retail transactions, a new restriction kicks in starting January 1, 2026:

• Individual Validation Required: Any single transaction exceeding RM10,000 must be issued as an individual e-invoice.
• No Consolidation: You are not allowed to include these high-value transactions in your monthly consolidated summary, even if the buyer does not request an invoice.

Employee Benefits & Staff Claims

One of the biggest “leakage” points in Form C deductions is staff reimbursements. For YA 2026, the rules are clearer:

• Proof of Expense: To remain tax-deductible, staff claims (petrol, parking, medical) should ideally be backed by e-invoices issued in the company’s name.
• The Employee Exception: If an e-invoice is issued in the employee’s name, it can still be accepted as a deductible expense if it aligns with a formal written Employer Policy and is justifiable as a business expense.
• Self-Billed e-Invoices: In certain cases, such as payments to foreign suppliers or specific local service providers, the employer may need to issue a self-billed e-invoice to validate the deduction.

Note: LHDN’s AI is now programmed to flag “Round Numbers” in staff claim categories. If your travel and entertainment expenses in Form C are exactly the same every month but lack a corresponding e-invoice trail, expect an inquiry.

How to Submit Form C via MyTax (Step-by-Step)

As of 2024, LHDN has made e-Filing mandatory for all companies. Manual paper submissions are no longer accepted for Form C. Follow this workflow to ensure a successful submission on the MyTax Portal.

Step 1: Access the MyTax Portal

Visit mytax.hasil.gov.my. Log in using the Director’s NRIC or the designated Tax Agent’s credentials. Ensure your digital certificate is active.

Step 2: Role Selection

Once logged in, look for the “Role Selection” dropdown at the top. You must switch your role from “Individual” to “Company Director” or “Employer” to see corporate tax options.

Step 3: Select e-Form C

• Navigate to ezHasil Services > e-Filing.
• Select e-Form and then choose e-C.
• Select the Year of Assessment (e.g., 2025).

Step 4: Fill and Verify Information

The form is divided into sections:

• Company Particulars: Pre-filled from SSM data; check for accuracy.
• Statutory Income: Enter figures from your audited accounts.
• Deductions & Incentives: Claim your capital allowances and SME-specific rebates here.
• Tax Payable: The system will automatically calculate your balance or refund.

Step 5: Sign and Submit

Click “Sign and Send.” You will be prompted to enter your NRIC/Passport number and your MyTax password as a digital signature.

Step 6: The MITRS Trigger

Crucial: After submission, do not close the browser. Look for the MITRS link or notification. You now have 30 days to upload your:

1. Audited Accounts (PDF)
2. Tax Computation (PDF)
3. Explanatory Notes

Note: Always download and save the Acknowledgement Receipt (Pengesahan) and the e-C PDF copy immediately. These are required by banks for loan applications and by LHDN during future audits.

Penalties for Non-Compliance in 2026

LHDN’s enforcement for Year of Assessment 2026 is increasingly automated through the MyTax portal. If your Form C data does not align with your e-Invoicing records or if deadlines are missed, the system triggers penalties under the Income Tax Act (ITA) 1967 without manual intervention.

Enforcement Triggers 

• The 60-Day Incremental Surcharge: Under Section 103, if the tax remains unpaid for 60 days after the initial 10% penalty is imposed, an additional 5% surcharge is levied on the remaining balance.
• MITRS Non-Compliance: Failure to upload your audited accounts and tax computation within the 30-day post-filing window is now considered an incomplete return.
• e-Invoicing Discrepancy: For YA 2026, if the revenue reported in your Form C is lower than the total validated e-Invoices in the MyInvois system, LHDN’s AI will flag the account for an immediate “Desk Audit” to request reconciliation.

Recommendation: If you discover an error after filing, make a Voluntary Disclosure before an audit begins. LHDN typically offers a lower penalty rate (often 10% to 15%) for self-corrections compared to the standard 100%–200% levied during an official investigation.

Conclusion: Master Your Form C Compliance

By staying ahead of the 7-month deadline and verifying your SME eligibility, you protect your company from unnecessary scrutiny and maximize your tax efficiency.

With the automation of LHDN’s enforcement, the margin for error has vanished. One mismatched e-invoice or a forgotten MITRS attachment can trigger a desk audit that consumes months of your time.

At Accounting.my, we specialize in navigating the complexities of the 2026 tax landscape so you don’t have to. Our Tax Service is designed to act as your company’s shield, ensuring that your Form C is not just “filed,” but strategically optimized.

How we help companies and directors:

• MITRS Management: We handle the end-to-end digital submission of your audited accounts and tax computations within the strict 30-day window.
• e-Invoice Reconciliation: We cross-verify your revenue against LHDN’s MyInvois data to flag discrepancies before they reach the tax office.
• SME Rate Optimization: We review your shareholding and capital structure to ensure you legally qualify for the 15%–17% tiered tax rates.
• Deadline Monitoring: We manage your filing calendar to ensure you never face the automatic 10% late payment surcharge.

Don’t leave your corporate compliance to chance. Let us handle the technical heavy lifting while you focus on growing your business.

Disclaimer: The information provided in this article is for general informational purposes only and does not constitute formal tax, legal, or professional advice.  Readers are advised to consult with a qualified tax professional or licensed auditor at Accounting.my before making any financial decisions or filing submissions based on this content.