Hong Kong profits tax filing deadline of 2 October 2026 is approaching for D-code companies with a December 2025 year-end that are filing electronically through a tax representative. This checklist covers eligibility for the extension, required documents, iXBRL preparation, e-filing procedures, and key compliance steps before submission.

The Inland Revenue Department (IRD) extended the 2025/26 Profits Tax filing deadline for “D” code companies (i.e., those with a December accounting year-end) under a circular letter issued on 14 July 2026. Paper filing moved from 17 August to 31 August 2026. Electronic filing moved further still, from 17 September to 2 October 2026.

That’s a genuine extension, not a standard block extension scheme date and with the e-filing deadline approaching, this checklist sets out exactly what December year-end companies with a tax representative still need to confirm before filing.

Who does this extension actually apply to?

This deadline applies specifically to companies with:

• An accounting year-end falling between 1 and 31 December 2025 (Accounting Date Code “D”)
• A properly appointed tax representative under the Inland Revenue Ordinance
• An intention to file electronically rather than on paper

If any of those three don’t apply to your company, this specific 2 October date isn’t yours. Companies filing on paper faced the earlier 31 August deadline. Companies without a tax representative were never on the block extension timetable at all. Their deadline was one month from the return’s original issue date, back in early May.

See also: Hong Kong Profits Tax Filing Guide 2026: Deadlines, Requirements and Preparation

Why this extension happened

The IRD doesn’t extend Block Extension Scheme deadlines lightly, and this year’s D-code extension reflects the broader shift toward mandatory and voluntary e-filing across the 2025/26 filing cycle, including new iXBRL requirements and the first year of mandatory e-filing for Hong Kong entities within large multinational groups meeting the BEPS 2.0 Pillar Two EUR 750 million threshold. Whatever the precise reasoning, D-code companies filing electronically have five extra weeks they didn’t have in the prior cycle, and tax representatives are being encouraged not to treat that as a licence to delay.

The filing checklist

Before you start

1. Confirm your company is actually a D-code case. Verify your accounting year-end falls within 1-31 December 2025 for this filing cycle. Don’t assume based on last year’s code if your company’s financial year-end has ever changed.
2. Confirm your tax representative appointment is current and on file with the IRD. The extended deadline only applies to represented cases. An appointment that’s lapsed or was never properly registered puts you back on the standard one-month timetable.
3. Confirm you’re filing electronically, not on paper. The 31 August paper deadline has already passed. If paper filing was your intention and you missed it, electronic filing under the extended 2 October date may now be your only compliant route forward. Raise this with your tax representative immediately if it applies to you.

Documents to prepare

1. Finalise audited financial statements. Since the 2022/23 year of assessment, corporations with gross income must submit audited accounts alongside the return. The former small-corporation concession no longer applies, except for formally dormant companies.
2. Complete the tax computation. This should reconcile accounting profit to assessable profit, reflecting any adjustments, allowances, and elections relevant to the 2025/26 year of assessment.
3. Prepare iXBRL-format financial statements if e-filing. The IRD’s Taxonomy Package and Data Preparation Tools were updated on 1 April 2026. You are advised to confirm you or your tax representative are working from the current version, not a prior year’s tools.
4. Gather supporting documentation for any claimed deductions or allowances. This includes documentation for R&D expenditure, IP-related deductions, or any preferential regime claims relevant to your business, filed using the correct supplementary forms.
5. Confirm your MNE group status. If your company belongs to a multinational group with consolidated revenue of EUR 750 million or more in at least two of the past four years, mandatory e-filing and iXBRL submission apply, and you should already be filing electronically regardless of this extension.

During the e-filing process

1. Verify your Business Tax Portal (BTP) or Tax Representative Portal (TRP) access is active. Paper-based block extension requests are no longer accepted, and portal access issues discovered close to the deadline leave little room to resolve them.
2. Submit supplementary forms electronically, even if any portion of your filing is otherwise on paper. This requirement applies regardless of your primary filing method.
3. Retain the Control List (Form IR1477) confirmation issued once your electronic forms are uploaded and ensure it’s signed by the same person signing the Profits Tax return itself.
4. Build in time for a final review before submission. Rushing a submission in the final days of an already-extended deadline defeats the purpose of having the extra time in the first place.

After filing

1. Confirm receipt of your filing acknowledgment from the IRD or portal and keep it with your records.
2. Note your provisional tax payment dates. Filing the return doesn’t end your obligations for the year. Provisional tax instalments tied to the following assessment will still fall due on their own schedule once your assessment notice is issued.
3. Review whether next year’s filing needs to start earlier. If this year’s preparation felt rushed even with the extension, that’s a signal to move audit and tax computation work earlier in the cycle next year rather than assuming another extension will materialise.

What happens if you miss 2 October?

The consequences follow the same structure as any other late Profits Tax filing: a fixed penalty typically starting at HK$1,200 for a first late return, escalating for continued non-compliance, alongside the possibility of an estimated assessment and additional tax of up to three times the amount undercharged in serious cases. Given that this deadline is already an extension on top of the original Block Extension Scheme date, there’s little practical basis to expect further leniency if it’s missed. You are advised to treat 2 October as firm.

Frequently asked questions (FAQs)

Does this 2 October deadline apply to every Hong Kong company?

No. It applies specifically to companies with a December 2025 accounting year-end (Code D) that have a tax representative and are filing electronically. Other accounting year-end codes, and companies without a tax representative, follow entirely different deadlines.

Is this extension a permanent change to the Block Extension Scheme calendar?

No. This is a specific extension for the 2025/26 filing cycle, announced by IRD circular letter on 14 July 2026. In the prior filing cycle, the equivalent D-code e-filing deadline was 15 September, not 2 October. This year’s date should not be assumed to repeat automatically next year.

What if my tax representative appointment isn’t currently registered with the IRD?

Then the extended block extension dates, including this one, don’t apply to you. Your deadline reverts to one month from your return’s original issue date. This is worth confirming urgently rather than assuming representation is in place.

I already missed the 31 August paper filing deadline—what are my options?

Electronic filing under the extended 2 October deadline may still be available depending on your circumstances. This should be raised with your tax representative immediately rather than waiting, since the options available narrow the longer it’s left unaddressed.

Does filing electronically by 2 October also cover my supplementary forms?

Supplementary forms must be filed electronically regardless of whether your main return is paper or electronic. If you’re using this extension for your main return, confirm your supplementary forms are being handled through the same process rather than assumed to follow automatically.

How Dezan Shira & Associates can help

Meeting the extended 2 October deadline requires more than simply submitting a return on time. Companies must ensure that their audited financial statements, tax computations, supplementary forms, and iXBRL submissions are prepared accurately and in accordance with the latest IRD requirements.

Dezan Shira & Associates assists businesses with profit tax return preparation and review, tax computation and supporting schedules, iXBRL reporting, e-filing compliance, and communication with the Inland Revenue Department. We also help companies assess their filing obligations under evolving digital reporting requirements, including mandatory e-filing rules for qualifying multinational groups, helping reduce compliance risks and avoid last-minute filing challenges. Contact us for customised support.