60 Days to Year-End: Is Your Compliance Calendar Ready?

Open your calendar and count forward from today. There are roughly 60 days left in 2026. It sounds like plenty, yet December has a way of disappearing: year-end holidays, closing stock counts, client deadlines and a team that is half on leave.

Meanwhile, the tax and GST departments do not slow down. A single month now holds an advance tax instalment, the last date for a belated income tax return and the annual GST return for FY 2025-26, along with the usual monthly filings. Miss one and you pay interest, late fees or both. Miss several and you spend January cleaning up.

This guide is a practical year-end compliance calendar for Indian businesses, professionals and salaried taxpayers with other income. You will find the dates that matter, a 60-day plan you can hand to your team, and the mistakes that most often lead to avoidable penalties.

The Short Version

15 December: Third advance tax instalment (75 percent of your estimated annual liability, cumulative).
31 December: Last date for a belated income tax return for AY 2026-27, and for the GST annual return (GSTR-9) and reconciliation statement (GSTR-9C) for FY 2025-26.
Revised returns: Revised returns now have a longer window under the Finance Act 2026. You can file one without a fee up to 31 December 2026, and with a fee until 31 March 2027.
Start the cleanup now. Reconciliation takes longer than filing.

Your December 2026 Date Map

Here are the main dates for the coming weeks. Confirm each one on the official portal before you file, because extensions and notifications can change them.

Date	What is due	Who it affects
7 December	Deposit of TDS and TCS deducted or collected in November	Businesses and anyone who deducts tax at source
11 December	GSTR-1 for November (monthly filers)	GST-registered businesses on monthly filing
13 December	Invoice Furnishing Facility (IFF) for QRMP taxpayers	Small taxpayers on the quarterly scheme
15 December	Third advance tax instalment (75 percent cumulative); PF and ESI contributions for November	Taxpayers with liability of ₹10,000 or more; employers
20 December	GSTR-3B for November (monthly filers)	GST-registered businesses on monthly filing
31 December	Belated ITR for AY 2026-27; end of the fee-free window for revised returns	Anyone who missed the original ITR date or needs to correct a filed return
31 December	GSTR-9 (annual return) and GSTR-9C (reconciliation) for FY 2025-26	GSTR-9 for turnover above ₹2 crore; GSTR-9C for turnover above ₹5 crore
Early 2027	Revised ITR with fee (until 31 March 2027); TDS returns for the October to December quarter, usually due by 31 January	Taxpayers revising returns; deductors

Your 60-Day Year-End Compliance Plan

Break the work into four short phases. Each one has a clear output, so nothing is left to the last week.

Phase 1: Now to 15 November, clean up the books

Update bookkeeping through October. Match bank statements with your ledgers.
Clear pending vendor and customer entries, and tag expenses correctly.
List every GSTIN, TAN and PAN you operate, with the person responsible for each.
Pull your Annual Information Statement (AIS) and Form 26AS and compare them with your books.

Phase 2: 16 to 30 November, reconcile and estimate

Reconcile purchase invoices with GSTR-2B and check that input tax credit claims are supported.
Compare GSTR-1, GSTR-3B and your books for FY 2025-26. Resolve differences before they appear in the annual return.
Estimate your income for the year and work out the advance tax due on 15 December.
Check TDS deducted and deposited against vendor and employee records.

Phase 3: 1 to 15 December, pay and file

Deposit TDS by 7 December and file GSTR-1 by 11 December.
Pay the third advance tax instalment and PF/ESI contributions by 15 December.
Have the draft GSTR-9 and GSTR-9C figures ready for review.

Phase 4: 16 to 31 December, close the year

File GSTR-3B by 20 December.
Finalise and file GSTR-9 and GSTR-9C. Aim to submit by 24 December, so any portal trouble does not hit the last day.
File any pending income tax return, or a revised return if you found an error, before 31 December.
Keep copies of all acknowledgements and challans in one shared folder.

Advance Tax: The 15 December Instalment

Advance tax is meant to spread your tax payment across the year. If your tax liability after TDS and TCS is expected to be ₹10,000 or more, you generally need to pay in instalments: 15 percent by 15 June, 45 percent by 15 September, 75 percent by 15 December and 100 percent by 15 March. Taxpayers under the presumptive scheme for small businesses and professionals are generally allowed to pay in a single instalment by 15 March, but confirm this for your own case.

Why it matters in December: missing an instalment attracts interest under sections 234B and 234C, and the cost builds up month by month. It is also a good moment to correct course. If business has been stronger than expected, your first two instalments may have fallen short, and paying the gap now reduces further interest.

Practical tip: estimate income for the full year, not just the months gone by. Include interest, rent, capital gains and any one-time receipts. Then subtract TDS you expect to be credited and pay the balance due as per the cumulative percentage.

GST Annual Return: GSTR-9 and GSTR-9C for FY 2025-26

The GST portal opened GSTR-9 and GSTR-9C for FY 2025-26 on 8 October 2026, according to a GSTN advisory dated 13 October 2026. The due date is 31 December 2026, and no extension had been announced at the time of writing. Do not plan around a hoped-for extension.

Businesses with turnover above ₹2 crore are required to file GSTR-9, and those above ₹5 crore must also submit the GSTR-9C reconciliation statement. The portal enables the annual return tile only once all GSTR-1 and GSTR-3B returns for the year have been filed, so clear any pending monthly returns first.

What to check before you file

Do your sales in GSTR-1, tax paid in GSTR-3B and your books agree? Differences between GSTR-1 and GSTR-3B are a common source of departmental queries.
Is every input tax credit claim supported by an invoice in GSTR-2B and a matching entry in your purchase register?
Have credit notes, debit notes and amendments been reported in the correct period?
Do HSN summaries, reverse charge entries and exempt supplies match your records?

Late filing of the annual return attracts a daily late fee, so filing on time saves money and avoids scrutiny. Smaller businesses below the turnover limits may be exempt from filing GSTR-9, but it is worth confirming with your advisor.

Income Tax Returns: Belated, Revised and Updated

If you missed the original due date for AY 2026-27, you can still file a belated return by 31 December 2026, with a late filing fee of ₹5,000 (reduced to ₹1,000 if your total income is up to ₹5 lakh) and interest on any tax unpaid. Delay also affects your ability to carry forward certain losses, which can be expensive for business owners and investors.

Up to 31 December 2026: Revise without any additional fee.
1 January to 31 March 2027: Revise with a fee of ₹1,000 if total income is up to ₹5 lakh, otherwise ₹5,000.

That longer window is useful, but it is not a reason to wait. Revising before 31 December costs nothing, and an early correction also reduces the interest that may build up.

If both the belated and revised windows are missed, an updated return (ITR-U) is available for up to 48 months from the end of the assessment year, but it comes with additional tax. Treat it as a last resort.

One more point: from 1 April 2026, income for the new tax year falls under the Income-tax Act, 2025, which uses the term “tax year” and renumbers many sections. Returns for FY 2025-26 (AY 2026-27) are still governed by the earlier Act, so older section numbers still apply to them.

TDS, Payroll and PF/ESI: The Small Dates That Cause Big Penalties

Large deadlines get attention, while small monthly ones quietly slip. Late TDS deposit attracts interest every month it stays unpaid, and failing to deduct tax where required can lead to a disallowance of the related expense. PF and ESI contributions, due by the 15th of each month, affect employees directly and invite penalties when delayed.

Set a recurring reminder for the 7th and the 15th, and assign one named person to each. Before the Q3 TDS return is filed in January, check that every deductee’s PAN is correct and that challans match the statement.

Companies and LLPs: Do Not Forget the Corporate Side

If you run a company or LLP, confirm that annual filings with the Registrar of Companies (such as financial statements and the annual return) are complete, that director KYC is current and that statutory registers and minutes are updated. These are easy to postpone because they sit outside the tax portal, yet late fees here are charged per day.

Looking Ahead: Your Year-End Tax Planning Window

Once December’s filings are done, you still have about three months until the financial year closes on 31 March 2027. Use this window to review your expected income, check whether your chosen tax regime still suits you, plan eligible investments and expenses, and settle outstanding receivables and payables on the right side of the year-end. Decisions made in January are harder to undo than decisions made now.

Seven Year-End Compliance Mistakes to Avoid

Planning around an extension. Extensions are never guaranteed. Work to the statutory date.
Filing GSTR-9 before reconciling. Errors in the annual return are hard to correct later.
Paying advance tax on past income. Estimate the full year, including one-time gains.
Ignoring AIS and Form 26AS. Mismatches with the department’s records trigger notices.
Leaving everything to the last week. Portal slowdowns peak on the final days.
No single owner. If everyone is responsible, nobody is. Assign each date to a named person.
Not saving acknowledgements. You will need them for audits, loans and visa or tender applications.

Your Year-End Compliance Checklist

Books updated and bank reconciled through the latest month
GSTR-2B reconciled with purchase records for FY 2025-26
GSTR-1, GSTR-3B and books compared, with differences explained
Advance tax estimated and paid by 15 December
TDS and TCS deposited by the 7th of each month
PF and ESI paid by the 15th of each month
GSTR-9 and GSTR-9C drafted and reviewed before 24 December
Pending or incorrect income tax returns filed or revised before 31 December
AIS and Form 26AS checked against your books
Acknowledgements, challans and working papers saved in one folder

Frequently Asked Questions

What is the deadline to deposit advance tax in December 2026?

The third advance tax instalment is due on 15 December 2026. By this date, you should have paid 75 percent of your estimated annual advance tax liability, counting earlier instalments.

What is the last date to file a belated ITR for AY 2026-27?

The last date is 31 December 2026. You will pay a late fee and interest on any unpaid tax. Missing this date leaves only the updated return (ITR-U) route, which carries additional tax.

Can I still revise my income tax return after 31 December 2026?

For AY 2026-27, the Finance Act 2026 extended the revised return window to 31 March 2027. Revising before 31 December 2026 has no additional fee, while later revisions carry a fee of ₹1,000 or ₹5,000 depending on total income.

When are GSTR-9 and GSTR-9C due for FY 2025-26?

Eligible taxpayers must complete and submit their GSTR-9 annual return and GSTR-9C reconciliation statement for FY 2025-26 on or before 31 December 2026 to avoid late fees and statutory penalties.

What happens if I miss an advance tax instalment?

You may owe interest under sections 234B and 234C. The amount depends on the shortfall and the number of months it stays unpaid, so paying the gap early limits the cost.

Should I hire a professional for year-end compliance?

If your business has multiple GST registrations, TDS obligations or a tax audit, professional support usually pays for itself through fewer errors and notices. At a minimum, have an expert review your reconciliations before the annual returns are filed.

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