December 2026 Tax Deadlines: Advance Tax, Belated ITR & GST Due Dates in Punjab

Reviewed by Kinsmen Corporate Advisory Group · Published 10 November 2026

Quick Answer (Executive Summary):
December 2026 is the most concentrated compliance month of Financial Year 2026–27. Business owners, partnership firms, and private limited companies in Punjab must navigate four major statutory cut-offs: the 15 December 2026 deadline for the third advance tax instalment (75% cumulative liability), and the 31 December 2026 hard stop for belated/revised ITRs (AY 2026–27), annual GST returns (GSTR-9 and GSTR-9C for FY 2025–26), and the FAST-DS foreign asset disclosure window. Missing these deadlines triggers daily late fees, mandatory interest under Section 234B/234C, and forfeiture of tax refunds.

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Key Takeaways

• 15 December 2026: Third instalment of Advance Tax due for FY 2026–27; cumulative payment must reach at least 75% of estimated net tax liability.
• 31 December 2026: Final statutory deadline to submit belated or revised Income Tax Returns for Assessment Year 2026–27 under Section 139(4) and Section 139(5).
• 31 December 2026: Statutory due date for annual GST returns GSTR-9 and self-certified reconciliation statements GSTR-9C for Financial Year 2025–26.
• 31 December 2026: Closure of the Foreign Asset Disclosure Scheme (FAST-DS 2026) for resident individuals with undisclosed foreign savings or shares.
• Immediate Financial Penalty: Missing 31 December ITR filing cuts off standard refund processing and forces taxpayers into ITR-U with a 25% to 50% additional tax surcharge.
• Punjab Focus: Commission agents, rice millers, and industrial units across Patiala, Ludhiana, Sangrur, and Malerkotla can coordinate integrated filings through Kinsmen’s Amargarh desk.

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What Are the Major Tax Compliance Deadlines in December 2026?

December is historically demanding for corporate finance desks and business owners because direct tax requirements and indirect tax annual reconciliations coincide within a two-week period.

Here is the statutory master schedule for December 2026:

Date	Statutory Provision	Target Taxpayer Group	Primary Legal Form	Governing Authority
07 Dec 2026	TDS / TCS Deposit	All deductors & collectors	Challan ITNS 281	Income Tax Department
10 Dec 2026	GSTR-7 & GSTR-8	TDS deductors & e-commerce operators	Portal Filing	GSTN / CBIC
11 Dec 2026	GSTR-1 (Monthly)	Regular taxpayers (Monthly outward supplies)	Form GSTR-1	GSTN / CBIC
13 Dec 2026	IFF (QRMP Scheme)	Quarterly filers (November B2B invoices)	Invoice Furnishing Facility	GSTN / CBIC
15 Dec 2026	Advance Tax (3rd Tranche)	Companies, LLPs, firms, individuals (>₹10,000 tax)	Challan ITNS 280 / e-Pay	Income Tax Department
20 Dec 2026	GSTR-3B (Monthly)	Regular taxpayers (November tax settlement)	Form GSTR-3B	GSTN / CBIC
31 Dec 2026	Belated & Revised ITR	Non-audit & audited assesses for AY 2026–27	ITR-1 to ITR-6	Income Tax Department
31 Dec 2026	GSTR-9 / GSTR-9C	Registered regular taxpayers (FY 2025–26)	GSTR-9 / GSTR-9C	GSTN / CBIC
31 Dec 2026	FAST-DS 2026	Resident individuals with foreign assets	Disclosure Form	CBDT / Black Money Act

Explore our dedicated Advance Tax Calculation service for advance tax scheduling.

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Who Must Pay the Third Instalment of Advance Tax by 15 December 2026?

Every taxpayer whose estimated net income tax liability for the financial year after deducting TDS/TCS exceeds ₹10,000 must pay advance tax in four quarterly tranches.

By 15 December 2026, non-corporate taxpayers, partnership firms, and companies must have discharged at least 75% of their total projected tax liability for FY 2026–27.

Key calculation checkpoints:

1. Gross Revenue Estimation: Estimate operational revenue and book profits up to 30 November 2026, projecting reasonable inflows for the remaining four months.
2. Factoring TDS Credits: Deduct TDS reflected in the Annual Information Statement (AIS) and Form 26AS.
3. Presumptive Tax Exemption: Small business owners opting for the presumptive taxation scheme under Section 44AD or professionals under Section 44ADA are exempt from the 15 December instalment; they pay 100% of advance tax in a single tranche on or before 15 March 2027.
4. Senior Citizen Relief: Resident individuals aged 60 years or older who do not derive any income from business or profession are entirely exempt from advance tax under Section 207(2).

Failure to pay at least 75% triggers mandatory interest at 1% per month for three months under Section 234C of the Income-tax Act, 1961 (carried into the Income-tax Act, 2025; most published concordance tables map old 234C to Section 425).

Learn more about managing return deadlines on our Income Tax Return Filing desk.

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Why Is 31 December 2026 the Hard Deadline for Belated and Revised ITRs?

Under Section 139(4) and Section 139(5), taxpayers who missed the primary July or October return deadlines have until 31 December 2026 to file their belated return or correct omissions in their original filing.

Consequence of Missing 31 December 2026:

• No More Revisions: You cannot revise your return under Section 139(5) after 31 December 2026. Errors discovered later cannot be corrected through a standard revision.
• Forfeiture of Losses: Business losses (speculative, non-speculative, or F&O derivative losses) cannot be carried forward to subsequent years if the return is filed belatedly, although unabsorbed depreciation can still be carried forward.
• Interest Under Section 234A: Accumulates at 1% per month on outstanding tax dues calculated from the original due date.
• Late Filing Fees Under Section 234F: ₹5,000 for total income exceeding ₹5 Lakh; ₹1,000 for total income up to ₹5 Lakh.
• ITR-U Burden: Any subsequent filing must follow the Updated Return route under Section 139(8A). An ITR-U requires paying an additional statutory penalty of 25% within 12 months, or 50% within 24 months, on aggregate tax plus interest.

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GSTR-9 and GSTR-9C Annual Return Rules for FY 2025-26

Financial Year 2025–26 annual GST filings close on 31 December 2026. Businesses registered under regular GST must reconcile their monthly filings with audited financial statements.

       [Aggregate Annual Turnover in FY 2025-26]
                          |
        -------------------------------------
        |                                   |
   Up to ₹2 Crore                      Above ₹2 Crore
        |                                   |
  GSTR-9 is EXEMPT                     GSTR-9 is MANDATORY
  (Filing is Optional)                      |
                                   -------------------
                                   |                 |
                             ₹2 Cr to ₹5 Cr     Above ₹5 Cr
                                   |                 |
                             Only GSTR-9        GSTR-9 + GSTR-9C
                                              (Self-Certified)

Critical Reconciliation Traps in GSTR-9:

1. GSTR-1 vs GSTR-3B Turnovers: Unreconciled outward supplies where tax was reported in GSTR-1 but not discharged in GSTR-3B must be paid through Form DRC-03 with 18% interest under Section 50.
2. Table 8D ITC Mismatch: Inward supplies reflected in Form GSTR-2B that were not claimed in monthly GSTR-3B before the statutory cut-off (30 November 2026) lapse permanently.
3. Credit Notes Accounting: Credit notes issued for sales return or post-sale volume discounts must be verified against recipient declarations.

View our comprehensive GSTR-9 Annual Return Filing advisory to coordinate reconciliation.

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Comparison: Regular vs Belated vs Updated Returns (ITR-U)

Understanding the legal differences between return categories helps business proprietors avoid unnecessary penalty surcharges:

Parameter	Original Return (Sec 139(1))	Belated Return (Sec 139(4))	Updated Return (Sec 139(8A))
Filing Window	Up to 31 July / 31 Oct 2026	Up to 31 December 2026	Up to 31 March 2029
Late Fee u/s 234F	₹0	₹1,000 or ₹5,000	₹1,000 or ₹5,000 + Surcharge
Additional Tax Penalty	Nil	Nil	25% or 50% extra tax
Carry Forward of Losses	Allowed for all business & capital losses	Loss lapsed (except depreciation)	Loss adjustment strictly restricted
Refund Eligibility	Fully processed with 0.5%/mo interest	Fully processed with reduced interest	No refund can be claimed
Deed & Remuneration Audit	Standard filing proof	Scrutiny review trigger	High-frequency verification

For related corporate compliance requirements, see our guide on Section 194T Partner TDS & Remuneration Rules.

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Step-by-Step December Compliance Action Plan for Punjab Enterprises

To complete all statutory requirements before the portal servers experience end-of-year traffic spikes, follow this sequential schedule:

1. Week 1 (1–7 December 2026): TDS & Accounting Close
   Audit vendor ledgers, compute Section 194C, 194J, and 194T withholding, and remit monthly TDS by 7 December via Challan ITNS 281.
2. Week 2 (8–14 December 2026): Advance Tax Computation
   Reconcile eight-month book profits with Tally or ERP statements. Project March 2027 closing numbers and calculate 75% tax dues.
3. Mid-Month (15 December 2026): Remit Advance Tax
   Pay advance tax through official bank net banking or the Income Tax e-Pay Tax portal to avoid Section 234C penal interest.
4. Week 3 (16–22 December 2026): GSTR-9 Turnover & ITC Mapping
   Run GSTR-2B vs purchase register comparisons. Identify any ineligible ITC claimed under Section 17(5) and compute DRC-03 settlements.
5. Week 4 (23–31 December 2026): Final Portal Filings
   Submit pending belated personal ITRs, upload GSTR-9/9C forms, and finalize FAST-DS applications before 31 December midnight.

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Local Advisory for Enterprises in Patiala, Ludhiana, Sangrur & Malerkotla

Business clusters across Punjab have sector-specific regulatory priorities in December:

• Grain Mandi Commission Agents (Arhtiyas) in Malerkotla & Sangrur: Reconcile APMC market fees and dami commission ledgers. Check that cash turnover respects Section 40A(3) limits before filing belated ITRs.
• Rice Millers in Nabha & Dhuri: Paddy procurement advances must be matched with bank stock statements and CC limit CMA projections for upcoming bank reviews.
• Textile & Hosiery Manufacturers in Ludhiana: Inverted duty structure ITC claims must be validated in annual GSTR-9 Table 6 to avoid audit requisitions from the Punjab state tax circle.
• Startups & Tech Firms in Mohali: File pending director KYC (DIR-3 KYC) and resolve corporate advance tax liabilities.

Kinsmen Corporate Services operates from our central office in Amargarh, providing direct in-person advisory for Malerkotla, Patiala, and Sangrur, and secure digital processing across Punjab.

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Frequently Asked Questions

What are the major tax deadlines falling in December 2026?

The four critical tax deadlines in December 2026 are: 15 December 2026 for the 3rd instalment of advance tax (75% cumulative liability); 31 December 2026 for belated and revised Income Tax Returns (ITR) for AY 2026–27; 31 December 2026 for annual GST returns GSTR-9 and reconciliation statement GSTR-9C for FY 2025–26; and 31 December 2026 for the FAST-DS foreign asset disclosure scheme window.

What happens if I miss filing my belated ITR before 31 December 2026?

After 31 December 2026, you permanently forfeit the statutory right to file a regular belated or revised return under Section 139(4) or 139(5). The only remaining remedy is an Updated Return (ITR-U) under Section 139(8A), which mandates paying an additional punitive tax penalty of 25% or 50% above your regular tax and interest liabilities.

Is GSTR-9 mandatory for all GST taxpayers in Punjab by 31 December 2026?

No. Small taxpayers with aggregate annual turnover up to ₹2 Crore in FY 2025–26 are exempt from mandatory GSTR-9 annual filing. For taxpayers with aggregate turnover exceeding ₹2 Crore, GSTR-9 is mandatory. For businesses exceeding ₹5 Crore, a self-certified GSTR-9C reconciliation statement is also required.

How much advance tax must be deposited by 15 December 2026?

All corporate entities and individual taxpayers (other than those opting for presumptive taxation under Section 44AD or 44ADA) must pay at least 75% of their total estimated net tax liability for FY 2026–27 cumulatively by 15 December 2026. Presumptive scheme taxpayers pay 100% by 15 March 2027.

Can a partnership firm revise its ITR after 31 December 2026?

No. Revisions under Section 139(5) close strictly on 31 December 2026 for Assessment Year 2026–27. While ITR-U permits reporting previously omitted income later, it does not permit reducing reported taxable profit, increasing carry-forward losses, or claiming higher refund amounts.

What is the penalty for missing the GSTR-9 deadline on 31 December 2026?

Under Section 47 of the CGST Act, late filing of GSTR-9 attracts a daily late fee of ₹50 per day (₹25 CGST + ₹25 SGST) for taxpayers with turnover up to ₹5 Crore, subject to a maximum statutory cap of 0.04% of turnover in the state. For turnover above ₹5 Crore, the fee is ₹200 per day up to 0.5% of turnover.

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Official Government Portals & Statutory Sources

• Income Tax Department Portal: incometax.gov.in — Advance tax calculation, e-Pay Tax, and ITR filing utility.
• Goods and Services Tax Portal (GSTN): gst.gov.in — GSTR-9 annual return and GSTR-9C reconciliation gateway.
• Central Board of Indirect Taxes and Customs (CBIC): cbic-gst.gov.in — Statutory GST notifications and turnover exemption circulars.
• Department of Revenue (CBDT): incometaxindia.gov.in — Circulars on Section 139(4), 139(8A) and FAST-DS guidance.

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Consult a Senior Tax Partner at Kinsmen

Avoid last-minute server congestion and statutory penalties. Speak directly with our tax advisory desk in Amargarh to prepare your advance tax computations, belated returns, and GSTR-9 reconciliations.

• Direct Phone: +91 99143-14949
• WhatsApp Consultation: Direct WhatsApp Consultation
• Office Location: Shop No. 1, Nabha Malerkotla Road, Amargarh – 148022, District Malerkotla, Punjab
• Online Form: Schedule a Consultation via Contact Desk