Urgent GST Compliance Checklist: What You Must Do Before March 31 2026

The clock is ticking for businesses across India to meet critical GST compliance deadlines by March 31, 2026. Missing these deadlines can lead to unnecessary tax burdens, penalties, and loss of valuable Input Tax Credit (ITC). This post highlights the absolute must-do tasks every business should complete before the deadline to stay compliant and avoid financial setbacks.

GST compliance form being filled out with calculator and pen

File the Letter of Undertaking (LUT) in Form RFD-11

Exporters and suppliers to Special Economic Zones (SEZ) must file the Letter of Undertaking (LUT) in Form RFD-11 for the upcoming financial year by March 31, 2026. This filing allows businesses to export goods or services without paying Integrated GST (IGST) upfront.

• Who should file: Exporters and SEZ suppliers who want to avoid paying IGST on exports.

• Why it matters: Without a valid LUT, exporters must pay IGST upfront and claim refunds later, which impacts cash flow.

• How to file: Submit Form RFD-11 online through the GST portal with accurate details.

• Example: A textile exporter who files LUT on time can ship goods without paying IGST immediately, improving working capital.

  
  

Failing to file LUT means exporters will face upfront IGST payments, increasing operational costs and delaying refunds.

Opt into the Composition Scheme Using Form CMP-02

Small businesses with turnover up to ₹1.5 crore can opt for the Composition Scheme, which simplifies GST compliance and reduces tax rates. The deadline to opt in for the financial year 2026-27 is March 31, 2026.

• Who should consider: Eligible small taxpayers looking for simpler tax filing and lower tax rates.

• Benefits: Quarterly returns instead of monthly, lower tax rates, and less paperwork.

• How to opt in: File Form CMP-02 on the GST portal before the deadline.

• Example: A small restaurant with ₹1 crore turnover can reduce tax burden and compliance effort by opting for the Composition Scheme.

  
  

Missing this deadline means businesses must continue under regular GST rules, which involve more frequent filings and higher tax rates.

Complete Vendor Reconciliation to Secure Input Tax Credit

Businesses must verify that their suppliers have uploaded all invoices correctly in the GST system to ensure they can claim full Input Tax Credit (ITC). This reconciliation is crucial before March 31, 2026.

• Why it matters: ITC claims depend on supplier invoice uploads. Missing invoices mean lost credits.

• How to reconcile: Compare purchase records with GSTR-2B auto-drafted data and communicate discrepancies to suppliers.

• Example: A manufacturer finds missing invoices from a supplier and requests them to upload the invoices to avoid ITC loss.

  
  

Regular vendor reconciliation prevents surprises during audits and improves cash flow by maximizing ITC claims.

Reset Invoice Numbering Starting April 1, 2026

GST rules require businesses to start a new sequential invoice numbering series from April 1 each financial year. This reset ensures clear audit trails and compliance.

• What to do: Begin invoice numbering at 1 or a new series on April 1, 2026.

• Why it matters: Continuous invoice numbers across years can cause confusion and non-compliance.

• Example: A retailer starts invoice numbers at 1 on April 1, making it easier to track transactions for the new financial year.

  
  

Ignoring this rule can lead to penalties and difficulties during GST audits.

Final Checklist Before March 31, 2026

• File LUT in Form RFD-11 if you export goods or supply to SEZ.

• Opt into Composition Scheme by filing Form CMP-02 if eligible.

• Complete vendor reconciliation to ensure all supplier invoices are uploaded.

• Reset invoice numbering to start fresh from April 1, 2026.

  
  

Meeting these deadlines protects your business from unnecessary tax payments, penalties, and ITC losses. Act now to secure your GST compliance and maintain smooth operations in the new financial year.

Take immediate action today to avoid last-minute rush and complications. Check your GST portal, communicate with your suppliers, and prepare your invoices for the new financial year. Staying ahead on GST compliance saves money and stress.