What This LHDN Announcement Means
LHDN is giving taxpayers advance notice that, from 15 August 2026 onwards, the MyInvois production system will strictly enforce format validation for 10 specific data fields in every e-Invoice submission.
Right now, submissions with format irregularities in these fields may still slip through.
After 15 August 2026, they will be rejected at the validation stage — meaning your e-Invoice won't get its Unique Identifier Number (UIN), won't get its QR code, and technically won't exist for tax purposes.
Why It Matters
Any ERP or accounting system that generates e-Invoices must be audited and reconfigured before 15 August 2026 to ensure the 10 fields comply.
Submissions that fail validation will need to be corrected and re-submitted, which delays revenue recognition, buyer downloads, and month-end closing.
For taxpayers who are only going live on 1 July 2026 (the concessionary implementation date), this leaves you roughly six weeks to test your system before strict validation kicks in — so the timing is tight.
The 10 Fields, Explained One by One
Field 1 — Supplier's Business Activity Description (max 300 characters).
This is the free-text field where the supplier describes what the business does (for example, "Wholesale of construction materials and hardware").
Going forward, it must be kept concise and within 300 characters.
Field 2 — e-Invoice Code / Number (max 50 characters).
This is your internal invoice reference number, such as "INV-2026-000123".
If your ERP generates invoice numbers longer than 50 characters — some legacy systems still do — you'll need to shorten the format before 15 August 2026.
Field 3 — e-Invoice Date (YYYY-MM-DD format, e.g. 2026-07-01).
This must follow the ISO 8601 date format.
No more DD/MM/YYYY, no more free-text like "1 July 2026".
Systems that send dates in local Malaysian format (DD-MM-YYYY or DD/MM/YYYY) will fail validation from that date onward.
Field 4 — Frequency of Billing (max 50 characters).
This describes how often billing occurs — "Monthly", "Quarterly", "Per delivery", and so on.
It should not be long paragraphs of explanation.
Field 5 — Unit of Measurement / UoM (must follow the provided unit codes).
LHDN publishes a standardised UoM code list — for example, "KGM" for kilogram, "LTR" for litre, "H87" for piece.
Free-text units will fail validation.
Your product master data likely needs to be mapped to the official codes, and this mapping exercise is usually where most Malaysian businesses will hit their biggest problem.
Field 6 — Supplier's Bank Account Number (max 150 characters).
This is the seller's bank account for payment purposes.
150 characters is generous — most bank accounts are far shorter — but the limit exists to prevent oversized payloads.
Field 7 — Payment Terms (max 300 characters).
A free-text field like "Net 30 days from invoice date" or "50% deposit, 50% on delivery".
Anything longer than 300 characters — such as pasting an entire contract clause — will fail.
Field 8 — Prepayment Reference Number (max 150 characters).
This is a reference to any prepayment or deposit already made by the buyer, tying the current invoice back to an earlier payment.
Field 9 — Incoterms (max 3 characters).
This is a strict format field. Incoterms are the standard 3-letter international trade codes — CIF, FOB, EXW, DDP, DAP, and so on.
Anything longer than 3 characters will fail.
That means you can no longer spell out "Cost, Insurance and Freight" — it must be shortened to just "CIF".
Field 10 — Authorisation Number for Certified Exporter (max 300 characters).
This is used only for taxpayers holding a Certified Exporter status, which is relevant for Free Trade Agreement preferential origin declarations.
Most taxpayers won't touch this field, but if you do, keep it under 300 characters.
What You Should Do Now
Start by auditing your existing ERP or e-Invoice middleware to check what each of these 10 fields currently outputs.
Then cross-check against the MyInvois SDK by downloading the latest version from the MyInvois developer portal to confirm each field's specification.
Fix the UoM mapping first — this is the most likely field to fail because most Malaysian businesses still use casual unit labels.
Fix the date format next; changing DD/MM/YYYY to YYYY-MM-DD is usually a straightforward ERP setting change.
And finally, test everything in the SDK sandbox environment well before 15 August 2026 — don't wait until the day of enforcement to discover that half your invoices are being rejected.
Malaysia