📅
FY 2025-26 closes on March 31 — don’t get caught off guard Every GST-registered business — exporter, MSME, startup, or trader — has specific year-end actions to complete. This checklist covers all 8 of them with exact forms, deadlines, and steps to follow.
8
GST Actions Before Mar 31
₹1.5Cr
Composition Scheme Turnover Limit
₹5Cr
E-Invoice Mandatory Threshold

As FY 2025-26 draws to a close, GST-registered businesses face a series of critical compliance deadlines — all converging on March 31, 2026. Whether you’re an exporter, an MSME owner, or a regular taxpayer, at least one of these 8 actions applies to you. Here’s a complete, plain-language guide to every action, every form, and every deadline.

1

LUT Renewal for Exporters

Form GST RFD-11 | Deadline: March 31, 2026 | Who: Exporters & SEZ suppliers

If your business exports goods or services, or supplies to SEZ units, you must file a fresh Letter of Undertaking (LUT) in Form GST RFD-11 before March 31, 2026 for FY 2026-27.

✅
What is an LUT and why does it matter?

An LUT is a declaration that allows you to export goods/services without paying IGST upfront. Without it, you must pay IGST on every export invoice and then claim a refund — which can lock up your working capital for months.

📌 Key Facts About LUT

  • LUT is valid for one financial year only (April 1 to March 31) — must be renewed every year
  • File on the GST portal: Services → User Services → Furnish Letter of Undertaking (LUT)
  • Eligibility: Any registered person making zero-rated supplies, provided they have not been prosecuted for tax evasion exceeding ₹2.5 crore
  • If you export SaaS, IT services, or any service to foreign clients — this applies to you
🚨
Miss the LUT Deadline?

If you don’t file by March 31, you must pay IGST on every export invoice from April 1 onwards and then wait months for a refund. This directly impacts your working capital and cash flow.

2

Composition Scheme Opt-In

Form CMP-02 | Deadline: March 31, 2026 | Who: Businesses with turnover under ₹1.5 Cr

Businesses with aggregate turnover up to ₹1.5 crore (₹75 lakhs for special category states) can opt into the GST Composition Scheme for FY 2026-27 by filing Form CMP-02 before March 31, 2026.

💰 Composition Scheme Tax Rates

Instead of filing monthly returns and charging full GST rates, composition dealers pay a simple flat rate:

1%
Manufacturers
(of goods)
5%
Restaurants
(food services)
6%
Service Providers
(mixed suppliers)

✅ Benefits of Composition Scheme

  • Much lower tax rates vs regular GST
  • File returns quarterly, not monthly
  • Dramatically reduced paperwork and compliance burden
  • No invoice-level detail required in returns

⚠️ Restrictions to Know

  • Cannot collect GST from customers
  • Cannot claim Input Tax Credit (ITC)
  • Cannot make inter-state supplies
  • Must reverse existing ITC if switching from regular scheme

⚠️ Switching from Regular → Composition? ITC Reversal Required

  • If you switch to the Composition Scheme from the regular scheme, you must reverse all ITC claimed on inputs (including WIP and finished goods stock) and capital goods
  • This reversal must be filed in Form ITC-03 by May 30, 2026
  • To exit the scheme in future, file Form CMP-04
3

ITC Reversal — Unpaid Vendor Invoices (Rule 37)

CGST Rule 37 | Deadline: March 31, 2026 | Who: All regular GST taxpayers

This is a very commonly missed year-end action. Under Rule 37 of the CGST Rules, if you have not paid a vendor within 180 days of the invoice date, you must reverse the ITC (Input Tax Credit) you already claimed on that invoice.

💡
Simple Example

You received a vendor invoice of ₹1,00,000 + GST ₹18,000 in September 2025. You claimed ITC of ₹18,000 in your GSTR-3B. But if you haven’t paid this vendor by March 2026 (180 days later), you must reverse that ₹18,000 ITC and pay interest on it.

✅ Steps to Follow for Rule 37 Compliance

  1. 1
    Run an aging analysis of all vendor payablesIdentify all outstanding invoices as of March 31, 2026. Flag every invoice that is more than 180 days old and unpaid.
  2. 2
    Check if ITC was claimed on those invoicesCross-reference with your GSTR-2B and GSTR-3B filings to see which of these invoices had ITC claimed.
  3. 3
    Reverse the ITC in your GSTR-3BShow the reversal in Table 4(B)(2) of GSTR-3B. Calculate and pay interest from the date ITC was originally availed.
  4. 4
    Reclaim ITC once you pay the vendorGood news — once you actually make the payment to the vendor, you can reclaim the ITC in the month of payment. It’s not lost forever, just deferred.
4

ITC Reversal — Exempt Supplies (Rule 42)

CGST Rule 42 | Deadline: March 31, 2026 | Who: Businesses with both taxable & exempt supplies

If your business makes both taxable and exempt supplies (for example, a hospital that provides both GST-taxable services and exempt medical services), Rule 42 requires you to reverse the portion of ITC that is attributable to exempt supplies.

📌 What You Need to Do

  • Calculate the proportion of exempt supplies vs total supplies for FY 2025-26
  • Apply this proportion to common ITC (ITC on inputs/input services used for both taxable and exempt supplies)
  • Reverse the proportionate ITC in your annual reconciliation before March 31
  • This is separate from Rule 37 — apply both checks independently
5

GSTR-2B Reconciliation with Your Books

GST Portal | Deadline: March 31, 2026 | Who: All GST-registered businesses

Before closing the financial year, you must reconcile your GSTR-2B auto-populated data with your books of accounts and GSTR-3B filings. Mismatches between GSTR-2B and GSTR-3B are the #1 trigger for ITC blocking and GST notices.

📋 GSTR-2B Reconciliation Checklist

  1. 1
    Match ITC: Books vs GSTR-2B (month by month)Go through April 2025 to February 2026 — for each month, compare ITC as per your purchase records with ITC visible in GSTR-2B. Note every mismatch.
  2. 2
    Identify unclaimed credits and file amendmentsIf your GSTR-2B shows ITC that you didn’t claim in GSTR-3B, claim it now (before the September 2027 deadline for FY 2025-26 credits).
  3. 3
    File all pending GSTR-1 and GSTR-3B returnsEven one unfiled return blocks your ITC for that month. Clear all pending filings before March 31.
  4. 4
    Chase vendors for missing invoicesIf a vendor hasn’t uploaded their invoice in GSTR-1, it won’t appear in your GSTR-2B. Contact them to upload it so you get the credit.
🚨
Important: ITC Lapse Deadline

ITC for FY 2025-26 that is not claimed by the time you file your September 2027 GSTR-3B return is permanently lost. Don’t leave unclaimed credits on the table.

6

Invoice Numbering Series Reset

CGST Rule 49 | Effective: April 1, 2026 | Who: All GST-registered businesses

As per Rule 49 of the CGST Rules, 2017, GST taxpayers should start a fresh invoice number series at the beginning of each financial year. Configure your billing software to reset or begin a new unique series from April 1, 2026.

⚠️ Why This Matters

  • Continuing the old series into FY 2026-27 can cause duplicate invoice number issues in GSTR-1 filing
  • It can also create complications in e-way bill generation where invoice numbers are validated
  • Simply inform your accounting team / billing software vendor to reset the series to INV/2026-27/001 or any fresh series from April 1
7

E-Invoicing Registration (₹5 Crore Threshold)

E-Invoice Portal | Deadline: March 31, 2026 | Who: Businesses crossing ₹5 Cr turnover

If your aggregate PAN-level turnover exceeded ₹5 crore in FY 2025-26, e-invoicing becomes mandatory for you from April 1, 2026. You must register on the e-invoice portal and integrate your billing system before the deadline.

✅ Steps to Register for E-Invoicing

  • Visit einvoice1.gst.gov.in
  • Register using your GSTIN credentials
  • Configure your billing/ERP software to generate IRN (Invoice Reference Number)
  • Test with a few invoices before April 1
  • Confirm your registration status is active

⚠️ What Happens If You Don’t Register

  • Invoices without IRN are invalid under GST law
  • Your customers cannot claim ITC on such invoices
  • You face penalty of ₹10,000 per invoice or 100% of tax amount
  • E-way bills cannot be generated for non-e-invoiced supplies
8

Additional Year-End GST Actions

Various | Deadline: March 31, 2026 | Who: As applicable

✅ GTA Forward Charge Declarations

  • If you use Goods Transport Agencies (GTAs) for transport, obtain fresh forward charge election declarations for FY 2026-27
  • These declarations document which party is responsible for paying GST on freight — critical for your ITC eligibility
  • GTAs must file their option on the portal by March 31 for it to apply from April 1

📌 Bank Account & Authorized Signatory Verification

  • Bank account on GST portal: Confirm your active bank account details are correct and updated — this is required for GST refund processing
  • Authorized signatory: Verify your signatory is still active and Aadhaar-authenticated. If there has been any change in company personnel, file Form GST REG-14 for the update
  • A mismatch or inactive signatory can block refunds and return filing

⚠️ QRMP Scheme — Opt-In or Exit by April 30, 2026

  • Taxpayers with aggregate turnover up to ₹5 crore can opt into or exit the Quarterly Return Monthly Payment (QRMP) scheme for FY 2026-27
  • Under QRMP: file GSTR-1 and GSTR-3B quarterly, but pay GST monthly using the IFF (Invoice Furnishing Facility)
  • Deadline to opt-in or exit: April 30, 2026 (one month after year-end, but plan your decision now)

📌 Complete GST Year-End Deadline Summary

# Action Required Form / Rule Deadline Who Must Act
1 LUT Renewal for FY 2026-27 Form GST RFD-11 March 31, 2026 Exporters, SEZ suppliers
2 Composition Scheme Opt-In Form CMP-02 March 31, 2026 Businesses under ₹1.5 Cr turnover
3 ITC Reversal — Unpaid Invoices (180+ days) Rule 37, CGST March 31, 2026 All regular GST taxpayers
4 ITC Reversal — Exempt Supplies Rule 42, CGST March 31, 2026 Mixed supply businesses
5 GSTR-2B Reconciliation with Books GST Portal March 31, 2026 All GST-registered businesses
6 Invoice Number Series Reset Rule 49, CGST April 1, 2026 All GST-registered businesses
7 E-Invoice Registration E-Invoice Portal March 31, 2026 Businesses with turnover above ₹5 Cr
8 GTA Declarations + Signatory Check Form GST REG-14 March 31, 2026 Businesses using GTA, changed signatories
+ ITC Reversal (Composition Switch) Form ITC-03 May 30, 2026 Those switching to Composition Scheme
+ QRMP Scheme Opt-In / Exit GST Portal April 30, 2026 Businesses with turnover under ₹5 Cr

🧑‍💼 What This Means for You

📊
CA / Tax Professional
  • Send advisory to all GST clients by March 25
  • Prioritise LUT renewals for export clients
  • Run ITC aging analysis for all clients
  • Reconcile GSTR-2B vs books for each client
  • Flag e-invoice requirement for clients crossing ₹5 Cr
💻
IT / SaaS Startup
  • File LUT renewal before March 31 — mandatory for zero-rated exports
  • Check if turnover crossed ₹5 Cr for e-invoicing
  • Reconcile GSTR-2B with books for FY 2025-26
  • Reset invoice series from April 1
🏭
MSME / Trader
  • Review Composition Scheme — does it make sense for FY 2026-27?
  • Run aging analysis — identify unpaid vendor invoices beyond 180 days
  • Clear all pending GSTR-1 / 3B returns immediately
  • Verify bank account details on GST portal are correct

💡 Don’t Wait Until the Last Week of March

Year-end GST compliance involves multiple actions across different portals — GST portal, TRACES, e-invoice portal. Each takes time. Start your reconciliation and filings this week so you’re not scrambling on March 29-31 when the portals are congested.

  • File LUT today if you’re an exporter — takes 5 minutes on the GST portal
  • Send aging report to your CA this week for Rule 37 review
  • Confirm e-invoicing readiness if your turnover is near ₹5 Cr
  • Check all pending returns — one unfiled return blocks your entire ITC chain

Need Help With GST Year-End Compliance?

Our GST experts at TaxServiceMitra.com can handle your LUT filing, ITC reconciliation, GSTR-2B matching, and e-invoicing setup — all before March 31. Don’t leave compliance to the last minute.

📞 Get Expert Help Now →

Disclaimer: This article is for informational purposes only and does not constitute legal or tax advice. GST rules and thresholds referenced are as per CGST Act, 2017 and applicable notifications. Please consult a qualified GST practitioner or CA for advice specific to your situation. Information is current as of March 2026 and published on TaxServiceMitra.com.