Tax Compliance Tracker: Sep 2023

Tax Compliance Tracker: September 2026

September 2026 is the single most compliance-dense month in the Indian financial year. By 30 September, you must file the tax audit report (Form 3CA/3CB/3CD) for AY 2027-28, deposit the second advance tax instalment covering 45% of your annual liability, complete DIR-3 KYC for every active DIN, file AOC-4 within 180 days of FY close, and shut the ITC window for FY 2025-26. Miss any one of these and penalties begin the next morning. Miss two and a cascade forms that disrupts October, November, and your statutory audit schedule.

The Complete September 2026 Deadline Calendar at a Glance

Before diving into each workstream, pin this master list. Every date below assumes the deadline falls on a working day; if a deadline falls on a Sunday or public holiday, it shifts to the next working day — but do not rely on that; file early.

Direct Tax Deadlines — Depth and Penalties

7 September: TDS and TCS Deposit

TDS deducted from payments made in August 2026 must reach the government account by 7 September 2026 (for non-government deductors). Government deductors who deduct and deposit on the same day use the 7th-of-following-month rule where challan is not involved.

Late deposit attracts interest under Section 201(1A) at 1.5% per month (or part thereof) from the date of deduction to the date of actual deposit — not merely from the due date. That distinction matters: if you deducted on 1 August and deposited on 20 September, the delay is two months, not one.

Worked figure: TDS of Rs. 5,00,000 deducted on 10 August and deposited on 20 September = 1.5 months (rounded to 2 months for interest). Interest = Rs. 5,00,000 × 1.5% × 2 = Rs. 15,000. If the delay exceeds the threshold, prosecution under Section 276B becomes a risk.

14 September: Issuing TDS Certificates

Form 16A (contract, professional fees, rent, interest), 16B (sale of property), 16C (rent paid by individuals under Section 194-IB), and 16D (fees to contractors/professionals by certain individuals) for TDS deducted in July 2026 must be issued to deductees by 14 September.

Download these from TRACES (tdscpc.gov.in) after the Q1 return (Form 24Q/26Q) is filed. Failure to issue certificates attracts Rs. 100 per day under Section 272A(2)(g), subject to a maximum equal to the TDS amount.

Practical check: Verify that the quarterly TDS return (Form 26Q for non-salary) for Q1 (April–June 2026) was filed and processed before you attempt to download Form 16A. A rejected or unprocessed 26Q blocks the certificate generation.

15 September: Second Advance Tax Instalment

Under Section 211 of the Income-tax Act 1961, advance tax for AY 2027-28 is due in four cumulative instalments:

• 15 June 2026: 15% of estimated annual tax
• 15 September 2026: 45% of estimated annual tax (cumulative)
• 15 December 2026: 75% (cumulative)
• 15 March 2027: 100%

The 15 September instalment is effectively 30% of annual tax if you paid the correct 15% in June. Assessees under presumptive taxation schemes (Sections 44AD, 44ADA) who opt in pay 100% in one shot by 15 March — they are not bound by the September date.

Interest for shortfall — Section 234C: If cumulative tax paid by 15 September falls short of 45% of assessed tax, interest accrues at 1% per month for 3 months on the shortfall.

Worked example: Your estimated annual income-tax liability for AY 2027-28 is Rs. 12,00,000. Cumulative advance tax paid by 15 September = Rs. 3,60,000 (only 30%, not the required 45% = Rs. 5,40,000). Shortfall = Rs. 1,80,000. Interest u/s 234C = Rs. 1,80,000 × 1% × 3 = Rs. 5,400. That is the floor; if total taxes paid by 31 March are still short, Section 234B interest layers on top.

Recalculate your projection before 15 September using actual H1 figures — do not use the prior-year tax as a proxy if business conditions have changed materially.

30 September: Tax Audit Report — Form 3CA/3CB/3CD

Section 44AB mandates a tax audit if your turnover exceeds:

• Rs. 1 crore (business) — raised to Rs. 10 crore where at least 95% of receipts and payments are through banking/digital channels
• Rs. 50 lakh (professional receipts)
• Certain deemed income cases under Sections 44AD(4) and 44ADA(4) where assessee opts out of presumptive scheme

The Chartered Accountant uploads Form 3CA (where accounts are already audited under another law, e.g., the Companies Act) or Form 3CB (where no prior statutory audit exists), together with Form 3CD (the 44-clause statement of particulars) on the income-tax e-filing portal at incometax.gov.in.

Penalty for non-filing: 0.5% of turnover or gross receipts, or Rs. 1,50,000, whichever is lower, under Section 271B. However, reasonable cause (e.g., hospitalisation of the auditor, genuine dispute on accounting treatment) can provide relief.

Form 3CD's high-risk clauses for September review: Clause 21 (cash payments above Rs. 10,000 u/s 40A(3)); Clause 34 (TDS compliance, including the often-missed Section 194Q for purchase of goods where turnover > Rs. 10 crore); Clause 26 (amount inadmissible under Sections 40 and 40A); Clause 44 (GST compliance summary — must agree with GSTR-9 data).

30 September: ITR for Audited Assessees

For AY 2027-28, assessees required to get accounts audited under Section 44AB must file their Income Tax Return by 30 September 2026 (subject to any CBDT extension). Transfer pricing cases have a separate 31 October deadline.

Applicable forms: ITR-3 (individual/HUF with business/professional income), ITR-5 (firms, LLPs, AOP), ITR-6 (companies). Late filing fee under Section 234F: Rs. 5,000 (Rs. 1,000 if total income ≤ Rs. 5 lakh). Additionally, filing after the due date converts a return from "original" to "belated," restricting carry-forward of most losses.

GST Deadlines — The ITC Cutoff Is the Sleeper Risk

Most teams focus on GSTR-3B and ignore the 30 September ITC hard stop. That is the most expensive mistake in the GST compliance calendar.

GSTR-1, GSTR-7, GSTR-8

GSTR-7 (TDS deductors under GST — government entities, PSUs) and GSTR-8 (TCS by e-commerce operators) for August 2026 are due 10 September. Late fee: Rs. 50 per day (Rs. 20 for nil returns), capped at Rs. 10,000.

GSTR-1 for monthly filers (August 2026 outward supplies) is due 11 September. File it on time — every invoice you upload becomes visible in your buyers' GSTR-2B for August, enabling them to claim ITC. A delayed GSTR-1 breaks the ITC chain for your customers.

QRMP-scheme taxpayers use the IFF (Invoice Furnishing Facility) by 13 September to upload B2B invoices for August. This is optional but essential if your buyers are monthly GSTR-3B filers — uninvoiced supplies will appear only in October's quarterly GSTR-1, which may cause ITC timing mismatches.

GSTR-3B and PMT-06

GSTR-3B for August 2026 is due 20 September for taxpayers with aggregate annual turnover above Rs. 5 crore. For others, the date is staggered to 22 or 24 September based on state category (as notified under Rule 61). Interest on late or short payment: 18% p.a. under Section 50 of the CGST Act, calculated from the due date to the actual date of payment.

QRMP taxpayers deposit August GST via PMT-06 by 25 September — either via the Fixed Sum Method (35% of last quarter's net tax) or the Self-Assessment Method (actual August liability computed from books).

30 September: The ITC and Credit Note Hard Cutoff

This is the deadline most businesses under-prepare for.

Section 16(4) of the CGST Act: ITC for invoices relating to FY 2025-26 cannot be availed after the earlier of (a) the due date of the September 2026 GSTR-3B return, or (b) the date of filing the annual return (GSTR-9).

Section 34(2): Any credit note issued by your supplier for FY 2025-26 supplies must be declared in GSTR-1 by 30 September 2026.

This means: if you missed claiming ITC on any FY 2025-26 vendor invoice — whether due to a late bill, a 2B mismatch, or simply oversight — and you do not claim it in the August 2026 GSTR-3B (due 20 September), that ITC is permanently lost under current law.

Action before 20 September: Reconcile your GSTR-2A/2B with your purchase register for all of FY 2025-26. Identify any unclaimed or mismatched ITC. Chase suppliers who have not filed their GSTR-1 to upload the invoice. Claim the balance in your August GSTR-3B.

MCA and Corporate Compliance — AOC-4 and DIR-3 KYC

AOC-4 Filing — 27 September 2026

Under Section 137 of the Companies Act 2013, every company must file its financial statements (Balance Sheet, P&L, Directors' Report, Auditors' Report) with the Registrar of Companies within 180 days of the financial year close. For FY 2025-26 (ending 31 March 2026), the deadline is 27 September 2026.

Forms required:

• AOC-4: All companies (standalone financials)
• AOC-4 CFS: Where consolidated financial statements are mandatory (Section 129(3))
• AOC-4 XBRL: Listed companies and certain unlisted companies as notified (use the current Ind AS XBRL taxonomy on MCA V3 portal at mca.gov.in)

Late filing fee: Rs. 100 per day per form — no cap, no maximum ceiling, effective from the day after the due date. File AOC-4 and AOC-4 CFS separately if applicable; each attracts its own late fee.

The practical sequence: Board approves draft financials → AGM adopts them → auditors sign off → AOC-4 filed within 30 days of AGM. Given AGM must happen by 30 September, and AOC-4 is due by 27 September, plan your AGM for mid-to-late September at the latest.

DIR-3 KYC — 30 September 2026

Every director who held an active DIN (Director Identification Number) as on 31 March 2026 must complete DIR-3 KYC by 30 September 2026. This is annual — it is not a one-time exercise.

Two filing modes:

1. DIR-3 KYC (full eForm): Required for first-time filers or where mobile number or email has changed since last KYC. Requires OTP verification on both mobile and email, plus a valid DSC.
2. DIR-3 KYC-Web: Web-based confirmation at mca.gov.in for directors with no changes to contact details. Takes under five minutes.

Consequence of non-filing: DIN is marked "Deactivated due to non-filing of DIR-3 KYC" with effect from 1 October 2026. A deactivated DIN means the director cannot sign any MCA e-form, board resolution, AOC-4, or annual return until the DIN is reactivated — which requires filing the DIR-3 KYC-Web form and paying a reactivation fee of Rs. 5,000 (as notified by MCA).

Annual General Meeting — 30 September 2026

Section 96 of the Companies Act 2013 requires every company (except a One Person Company) to hold its AGM within six months of the financial year end — i.e., by 30 September 2026.

Minimum notice period: 21 days' clear notice to members (Section 101). Shorter notice is valid only if at least 95% of shareholders consent in writing. An AGM held with 18 days' notice (a common shortcut) is procedurally invalid, which in turn invalidates the adoption of financial statements, stalling AOC-4.

Payroll and Labour Compliance — 15 September and State Layers

EPFO and ESIC: August 2026 contributions are due 15 September. EPFO damages for late deposit range from 5% to 25% per annum under Para 32B of the EPF Scheme based on delay duration. ESIC interest runs at 12% p.a. simple.

Professional Tax: Varies by state. Maharashtra: monthly payment by 15th for employers with more than 20 employees. Karnataka: slab-based monthly deposit for employers with more than five employees. West Bengal: operates on a half-yearly cycle.

Multi-state businesses should maintain a state-by-state compliance matrix updated each quarter, with a designated regional owner for each cluster of states. Central compliance discipline frequently masks a missed PT return in a branch state — which then surfaces as a notice in Q3.

Worked Example: The Cascade of Three Missed Deadlines

Entity: ABC Consulting LLP. Two designated partners. Annual professional receipts: Rs. 80 lakh (AY 2027-28). GST-registered monthly filer. Net GST payable for August 2026: Rs. 2,00,000.

Scenario: The LLP's CA firm is overloaded in September. Three things slip.

Miss 1 — Tax audit report filed 20 October (20 days late) Penalty u/s 271B = 0.5% of Rs. 80 lakh = Rs. 40,000. (Below the Rs. 1,50,000 cap, so the full Rs. 40,000 applies.)

Miss 2 — DIR-3 KYC not filed for both partners DINs deactivated from 1 October 2026. Reactivation fee = Rs. 5,000 × 2 = Rs. 10,000. Partners cannot sign ITR verification (Form ITR-V) or any MCA form until reactivated — this pushes the ITR filing further into November, attracting a late filing fee of Rs. 5,000 u/s 234F.

Miss 3 — GSTR-3B filed 25 September (5 days late) Late fee = Rs. 50 × 5 = Rs. 250. GST interest = Rs. 2,00,000 × 18% × 5/365 = Rs. 493.

Total direct penalties: Rs. 40,000 + Rs. 10,000 + Rs. 5,000 + Rs. 250 + Rs. 493 = Rs. 55,743

The indirect costs are harder to quantify but more damaging: statutory auditor displeasure, disrupted Q2 filings for the partnership, and a GSTIN flagged for late filing which can affect e-way bill generation.

Common Mistakes That Recur Every September

1. Form 3CD filed with stale Clause 34 data. TDS compliance under Section 194Q (purchase of goods where buyer's turnover > Rs. 10 crore) is routinely missed because it was introduced relatively recently and many preparers still overlook it in the clause-by-clause review.

1. ITC reconciliation left to October. The 30 September cutoff for FY 2025-26 ITC means reconciliation must be complete by 18–19 September. Teams that start in October find the door permanently closed.

1. DIR-3 KYC assumed to be one-time. Directors who filed their first DIR-3 KYC years ago often receive a deactivation notice with no warning because no reminder was set.

1. AOC-4 XBRL submitted with wrong taxonomy version. MCA V3 uses the current Ind AS XBRL taxonomy; using outdated tools generates validation errors and portal rejections. File by 22 September to allow three working days for corrections before the 27th.

1. Advance tax not recalculated post-H1. Using prior-year tax as the benchmark ignores material swings in FY 2026-27 profitability — particularly relevant after GST demand notices, contract wins, or asset sales in H1.

1. AGM notice period cut short. Sending notice on 12 September for an AGM on 29 September gives only 17 clear days. This invalidates the meeting under Section 101.

1. Missed unclaimed ITC from October 2025–March 2026 period. Bills received late from vendors are often posted in the following month and can slip out of GSTR-2B matching. Run a line-by-line GSTR-2B vs. books reconciliation — not just a summary check — before the September GSTR-3B.

Building Your September War Room — Step by Step

Step 1 — Entity mapping (by 20 August) List every legal entity you manage: companies, LLPs, proprietorships, trusts, each GST registration separately. Map each entity to each September deadline. Some entities have three or four applicable deadlines; others may have only advance tax and TDS.

Step 2 — Assign single-point ownership (by 25 August) One named person owns each workstream — direct tax, indirect tax, corporate MCA, payroll. For multi-entity practices, build an entity × deadline matrix in Excel or a dedicated compliance tool. Shared ownership = no ownership.

Step 3 — Pre-flight checks (1–10 September)

• Reconcile GSTR-2B vs. purchase register for all of FY 2025-26
• Run Form 3CD pre-check across Clauses 12, 16, 21, 26, 34, 44
• Verify all DINs are active on MCA V3 portal — do not wait for the 30th to discover deactivations
• Confirm advance tax computation reflects revised H1 2026-27 projections
• Issue AGM notice by 8 September (for a 29 September AGM with 21 clear days)

Step 4 — Filing sprint with buffer dates (10–30 September)

• 10 Sep: GSTR-7, GSTR-8
• 11 Sep: GSTR-1
• 13 Sep: GSTR-1 IFF
• 14 Sep: TDS certificates
• 15 Sep: Advance tax, PF, ESI, Professional Tax
• 20 Sep: GSTR-3B (or staggered date)
• 22 Sep: Internal AGM
• 24 Sep: AOC-4 submission (3 working days before 27th)
• 25 Sep: PMT-06
• 27 Sep: DIR-3 KYC-Web for all directors (3 days before deadline)
• 28 Sep: Tax audit report signed and uploaded
• 29 Sep: ITR filed for audited assessees

Step 5 — Daily standup (last 10 working days) Fifteen minutes at 9 a.m.: what was submitted yesterday, what is due today, any blockers. Single traffic-light dashboard — green (filed), amber (in progress), red (not started) — visible to every team member and the partner-in-charge.

Key Takeaways

• 30 September is a five-deadline day: tax audit report, ITR for audited assessees, DIR-3 KYC, AGM, and GST ITC cutoff all converge. Build in a 3-day buffer for each.
• The ITC cutoff is permanent. Any unclaimed FY 2025-26 ITC not reflected in the August GSTR-3B is lost; reconcile by 18 September.
• DIR-3 KYC is annual, not one-time. A deactivated DIN cascades into ITR delays, MCA filing blocks, and Rs. 5,000-per-director reactivation fees.
• Advance tax shortfall compounds. Interest u/s 234C accrues at 1% per month for 3 months on the September shortfall — recalculate using actual H1 numbers before the 15th.
• AOC-4 XBRL rejection costs 3–5 working days. File by 22–24 September on MCA V3 with the current taxonomy to allow correction time before the 27th.
• The Rs. 100/day MCA penalty has no ceiling. A 60-day AOC-4 delay costs Rs. 6,000 per form — trivial compared to the disruption of deactivated DINs or lapsed ITC.
• War-room discipline pays for itself. A structured September close — mapped deadlines, named owners, daily standup — costs a few hours of planning; one missed September deadline costs multiples of that in penalties and cascading delays.