TL;DR
Before 31 March 2026, ensure you:
- Start new GST invoice series from 1 April
- File revised TDS returns (last chance)
- Apply for LUT (exporters)
- Review AIS & Form 26AS
- Pay advance tax shortfall
- Complete GST reconciliation
- Verify stock, bank & loan balances
- File ITR-U (final deadline for AY 2021-22)
Miss this window → penalties, interest & compliance risks
Why 31 March 2026 is a Hard Deadline
This is not just year-end—it is a regulatory cut-off where:
- Tax benefits expire
- Correction windows close
- Compliance mismatches trigger notices
A single oversight can result in interest, disallowances, or scrutiny.
13 Critical Compliance Actions Before 31 March 2026
1. New GST Invoice Series for FY 2026-27
From 1 April 2026, businesses must:
- Start a fresh invoice numbering sequence
- Ensure no duplication or overlap
Non-compliance can lead to GST audit issues
2. Revised TDS Return – Final Opportunity
Deadline: 31 March 2026
Applicable for:
- FY 2018-19 (Q4)
- FY 2019-20 to 2023-24 (Q1–Q3)
This is the last correction window
After this → errors become permanent
3. Apply for LUT for FY 2026-27
Exporters must file Letter of Undertaking (LUT) to:
- Export without IGST
- Supply to SEZ without tax payment
Without LUT → cash flow blockage due to IGST
4. Review AIS and Form 26AS
Critical verification includes:
| Area | What to Check |
|---|---|
| TDS/TCS | Matches with books |
| SFT Transactions | Property, mutual funds |
| Bank Data | Cash deposits |
Mismatch = Income tax notice risk
5. Advance Tax Payment
If unpaid/shortfall exists:
- Pay before 31 March 2026
- Reduce interest under:
- Section 234B
- Section 234C
6. GST Reconciliation (GSTR-1 vs GSTR-3B vs GSTR-2B)
Must reconcile:
- Outward supplies
- ITC claims
- Books of accounts
This is one of the most scrutinized areas in GST audits
7. Closing Stock Verification
- Conduct physical stock check
- Match with books
Mismatch → affects:
- Profit calculation
- Tax liability
8. Bank & Loan Reconciliation
Ensure:
- All bank balances match books
- Loan interest recorded correctly
Errors impact financial statements and tax reporting
9. Updated Return (ITR-U) for AY 2021-22
Deadline: 31 March 2026
Use case:
- Missed income
- Incorrect reporting
This is the last chance ever to correct FY 2020-21 returns
10. Investment for Deductions Under Chapter VI-A
For taxpayers opting for the old tax regime, ensure investments are completed before 31 March 2026:
| Section | Investment Type | Limit |
|---|---|---|
| 80C | ELSS, PPF, LIC, FD | ₹1.5 lakh |
| 80D | Health Insurance | ₹25,000–₹50,000 |
| 80G | Donations | As applicable |
| 80CCD(1B) | NPS (National Pension System) | ₹50,000 (additional) |
Strategic Insight:
- NPS provides extra deduction over 80C, making it one of the most underutilized tax-saving tools
- Ideal for long-term retirement planning + immediate tax benefit
Missing this = direct tax outflow increase
11. Applicability of TDS & TCS
If turnover exceeds:
| Category | Threshold |
|---|---|
| Business | ₹1 crore |
| Profession | ₹50 lakh |
Then:
- TDS/TCS becomes mandatory
Plan systems now to avoid future penalties
12. TDS on Salary
Employees must:
- Submit investment proof
- Declare tax regime
Employers must:
- Deduct correct TDS in March
Common Errors That Trigger Notices
- GST mismatch (GSTR vs books)
- Ignoring AIS data
- Missing TDS corrections
- Wrong ITC claims
- No LUT filing
Final Week Execution Plan
| Timeline | Action |
|---|---|
| Day 1–2 | Tax planning + investments |
| Day 3–4 | GST & AIS reconciliation |
| Day 5–6 | TDS & bank review |
| Day 7 | Final compliance audit |
13. PTEC Payment (₹2500)
- Deadline: 31 March 2026
- Applicable for professionals in Maharashtra
Step-by-Step Year-End Closing Strategy
- Start with reconciliation (GST + bank)
- Review tax exposure (advance tax + TDS)
- Validate compliance documents
- Execute tax-saving investments
- Finalize books & audit trail
Common Mistakes to Avoid
- Ignoring AIS mismatches
- Late advance tax payments
- Missing LUT renewal
- Incorrect GST reconciliation
- Skipping stock verification
Conclusion
March ending is a compliance battlefield—not just a deadline.
Businesses and individuals who act early:
- Save tax
- Avoid penalties
- Stay audit-ready
For end-to-end GST, TDS, and tax compliance support, consult CAK & Associates LLP—your strategic CA partner in Pune.
6. FAQ SECTION
1. What is the last date for revised TDS return filing?
31 March 2026 is the final deadline for eligible financial years. No corrections allowed after this.
2. Is LUT mandatory for exporters every year?
Yes. A fresh LUT must be filed annually to export without paying IGST.
3. Why should AIS and Form 26AS be reviewed?
To ensure all reported income, TDS, and transactions match your records and avoid notices.
4. Can advance tax be paid after 15 March?
Yes, but paying before 31 March helps reduce interest under Sections 234B & 234C.
5. What happens if GST reconciliation is not done?
It can lead to ITC denial, penalties, or GST notices.
6. Who is liable for TDS/TCS from April 2026?
Individuals/HUFs exceeding ₹1 crore (business) or ₹50 lakh (profession) turnover.
