GSTR-1 Table Wise Details Explained: The Definitive Compliance Guide for 2026

GSTR-1 Table Wise Details Explained: The Definitive Compliance Guide for 2026

By CA Devesh Thakur

Introduction

As India moves deeper into the digital taxation era, accurate and compliant GST reporting has become essential for every business — whether micro, SME, or enterprise-level.
Among all GST returns, GSTR-1 is the backbone of the outward supply reporting system. Every detail you file here impacts:

• Your buyer’s ITC reflection in GSTR-2A/2B
• Your own GSTR-3B liability
• E-commerce reconciliations
• GST departmental scrutiny
• Annual returns under GSTR-9/9C

However, with the 2026 compliance updates and increased system validations, even small mistakes inside GSTR-1 can trigger notices, mismatches, penalties, or ITC disputes.

This guide is the most comprehensive and updated explanation of every GSTR-1 table, written exclusively for the 2026 compliance landscape — ensuring you file error-free returns and stay fully protected.

What is GSTR-1? (2026 Update)

GSTR-1 is a mandatory GST return filed by registered taxpayers to disclose all outward supplies for a tax period. This includes:

• Regular sales (B2B/B2C)
• Export supplies
• SEZ supplies
• Credit/Debit Notes
• E-commerce sales
• Advance received and adjustments
• Document summary
• Amendments from previous periods

As GSTN strengthens AI-driven validations in 2026, the accuracy of table-wise reporting becomes more crucial than ever.

Why GSTR-1 Accuracy Matters in 2026

Filing GSTR-1 properly ensures:

✔ Correct ITC reflection for your customers

Buyers rely on your GSTR-1 for claiming Input Tax Credit. Any error affects their compliance.

✔ Avoidance of GST Department Notices (DAX, ASMT, DRC)

Mismatch between GSTR-1 vs GSTR-3B or over-reporting now triggers automated scrutiny.

✔ Smooth export & refund processing

Zero-rated supplies must match across tables to avoid delays.

✔ Accurate e-commerce tax compliance

Especially for Amazon, Meesho, Flipkart, and 9(5) category services.

✔ Clean annual return under GSTR-9 & audit readiness under GSTR-9C

GSTR-1 Table-Wise Explanation (2026 Professional Edition)

Below is the enhanced, updated, and compliance-focused breakdown of every table in GSTR-1, written with CA-level precision.

Table 4A – B2B Outward Supplies (Registered, Non-RCM)

This is the core of GSTR-1.
It includes all taxable supplies made to registered buyers under normal GST.

Purpose (2026)

To report invoice-level details of outward supplies where:

• Recipient is registered
• Tax is payable by the supplier
• Supplies are made directly or via e-commerce operators

Importance:

This table directly auto-populates the buyer’s GSTR-2B ITC. Errors here = disputes + notices.

Table 4B – B2B Reverse Charge Supplies (Supplier → RCM)

Report supplies where the recipient is liable to pay GST under reverse charge.

Examples:

• Transportation (GTA) services
• Legal services
• Sponsorship to body corporate

2026 Compliance Note:

Misclassification here triggers RCM liability notices under Section 9(3).

Table 5 – B2CL (Inter-State Supplies > ₹1,00,000)

High-value inter-state unregistered sales belong here.

Purpose:

To ensure visibility of large unregistered outward supplies for compliance tracking.

Table 6A – Export Supplies (Zero-Rated)

Applicable for exports:

• With payment of IGST
• Without payment of IGST under LUT

2026 Update:

Export mismatches now undergo automated validation with ICEGATE data.

Table 6B – Supplies to SEZ (With/Without IGST)

Zero-rated supplies made to:

• SEZ Units
• SEZ Developers

Key Requirement:

Invoice must be endorsed by SEZ authority.

Table 6C – Deemed Exports

Supplies notified as deemed export under GST, such as:

• EOU units
• AA license holders
• EPCG holders

Note:

Recipient often claims refund of tax paid.

Table 7 – B2C (Others) – Small Unregistered Supplies

The summary of all retail & consumer-level outward supplies.

Includes:

• Cash sales
• POS-based outward supplies
• E-commerce low-value orders

2026 Compliance Risk:

Wrong POS classification triggers IGST vs CGST/SGST mismatch notices.

Table 8 – Nil-Rated, Exempted & Non-GST Supplies

This table ensures tax-free supplies are properly declared.

Include:

• Nil-rated goods
• Exempt services
• Petroleum products, liquor (Non-GST)

Purpose:

GSTN uses this for turnover risk analysis.

Table 9A – Amendments to Previous Period Invoices

Correct any past errors in:

• B2B supplies
• B2CL
• Exports
• SEZ
• Deemed exports

Pro Tip 2026:

Ensure amendment month matches actual invoice correction month, not invoice date.

Table 9B – Credit/Debit Notes (Registered)

Report:

• Reduction in taxable value (Credit Note)
• Increase in taxable value (Debit Note)

Key Impact:

Affects both seller’s liability and buyer’s ITC.

CDNUR – Credit/Debit Notes for Unregistered Buyers

Used for adjusting B2C sales.

2026 Note:

E-commerce B2C adjustments must match operator TCS data.

Table 9C – Amendments to CDN / CDNUR

Corrections to previously issued credit/debit notes.

Table 10 – Amendments in B2C (Others)

Fix earlier period B2C entries.

Table 11A – Advances Received (Invoice Not Issued)

Applicable mostly for SERVICE providers.

Purpose:

Tax must be paid on advances for services.

Table 11B – Adjustment of Advances

When invoice is later issued, adjust the advance tax paid earlier.

Table 12 – HSN Wise Summary of Outward Supplies

This table is highly scrutinized in 2026.

Purpose:

Helps GSTN compare:

• Sectoral tax trends
• Rate-wise turnover
• High-risk classification mismatches

Mandatory:

Even small taxpayers must furnish 6-digit HSN for top commodities.

Table 13 – Documents Issued Summary

Includes:

• Tax invoices
• Credit Notes
• Debit Notes
• Refund Vouchers
• Delivery Challans

Why Important:

System matches document count with declared outward supplies.

Table 14 – E-Commerce Operator (ECO) Transactions

Applies if supplies are made through platforms such as:

• Amazon
• Meesho
• Flipkart
• Zomato
• Uber/Ola (for transport services)

Sections Covered:

• Section 52 – TCS by operator
• Section 9(5) – Operator pays GST instead of supplier

2026 Update:

High mismatch detection via TCS 52 report integration.

Table 15 – Supplies Under Section 9(5)

Operator pays GST on behalf of suppliers for specific services.

Examples:

• Restaurant services by non-AC outlets
• Housekeeping services
• Certain notified online services

Common Errors in GSTR-1 (2026 Focus)

Avoid these to stay fully compliant:

❌ Reporting B2C invoices in B2B
❌ Wrong GSTIN of recipient
❌ Incorrect POS leading to IGST/CGST+SGST mismatch
❌ Missing HSN details
❌ Not reporting credit notes
❌ Amendment entries in wrong table
❌ E-commerce supplies not matching TCS reports
❌ Duplicate invoice entries

Expert Tips to File Error-Free GSTR-1 in 2026

✔ Reconcile data with books every month

✔ Match E-commerce operator reports (TCS, Settlement)

✔ Verify GSTINs using GST Search

✔ Ensure e-invoice and GSTR-1 data sync

✔ Maintain rate-wise summary

✔ Check auto-populated data before filing

Conclusion

GSTR-1 is no longer just a monthly compliance requirement — it’s a powerful document that determines:

• Your tax liability
• Your buyer’s ITC
• Your annual return accuracy
• Your risk rating under GST

With the 2026 compliance enhancements, businesses must adopt precise, table-wise reporting. By understanding each table in GSTR-1 and filing it accurately, you ensure:

✔ Zero notices
✔ Clean ITC flow
✔ Full compliance
✔ Better financial health
✔ Strong GST credibility

As a GST practitioner, I always advise:
“A perfectly filed GSTR-1 is the foundation of your entire GST compliance ecosystem.”