GSTR-2A, GSTR-2B, and GSTR-3B: Complete Blueprint

Every GST-registered business in India must navigate three closely connected government statements each month: GSTR-2A, GSTR-2B, and GSTR-3B. Understanding the difference between them — and the precise sequence in which they interact — is the foundation of accurate Input Tax Credit (ITC) management and audit-proof monthly compliance.

Getting this wrong is costly. Claiming ITC from the wrong source, missing the 14th-of-month cutoff, or failing to reconcile your purchase register against GSTR-2B can lead to excess ITC demands, interest under Section 50, and show-cause notices from the tax department.

Understanding GSTR-2A: The Dynamic, Auto-Populated Statement

GSTR-2A is a read-only, auto-populated purchase statement generated by the GST portal for every registered taxpayer. It is populated automatically from the data that your suppliers upload when they file their outward supply returns — primarily GSTR-1, GSTR-5 (for non-resident taxpayers), and GSTR-6 (for Input Service Distributors).

The defining characteristic of GSTR-2A is that it is dynamic: it updates continuously throughout the year. If your supplier files an amended GSTR-1 in December to correct an invoice from July, that amendment will appear in your GSTR-2A in December. There is no month-end cutoff for GSTR-2A.

GSTR-2A is useful for tracking the overall compliance behavior of your suppliers — it gives you a running picture of which vendors are filing on time and which invoices they have declared. However, since the Finance Act 2021, GSTR-2A is not the valid basis for ITC claims. That role now belongs exclusively to GSTR-2B.

Understanding GSTR-2B: The Static Monthly Statement and the Legal Basis for ITC

GSTR-2B is a static, auto-drafted ITC statement generated on the 14th of every month. It is a frozen snapshot that captures all invoices uploaded by your suppliers in their GSTR-1 filings between the 14th of the previous month and the 13th of the current month.

Unlike GSTR-2A, once GSTR-2B is generated on the 14th, it does not change. A supplier filing their GSTR-1 on the 15th or later will not appear in the current month's GSTR-2B — their invoice will instead appear in the next month's GSTR-2B.

Section 16(2)(aa) of the CGST Act, 2017 (inserted by the Finance Act 2021 and made effective from 1 January 2022) explicitly mandates that ITC can only be availed for invoices or debit notes that are reflected in the taxpayer's GSTR-2B. This makes GSTR-2B the only legally valid and statutory basis for ITC availing under Rule 36(4). Reconciling your books against GSTR-2B before filing GSTR-3B is not optional — it is a legal requirement.

Understanding GSTR-3B: The Monthly Self-Assessment Summary Return

GSTR-3B is the monthly summary return where registered taxpayers declare their outward tax liability, claim eligible ITC, and pay the net tax due to the government. It is a self-assessment return — the taxpayer calculates and reports figures without waiting for a government assessment.

In GSTR-3B, Table 3 reports outward taxable supplies (sales), and Table 4 reports eligible ITC claims. The GST portal auto-populates Table 4 using the GSTR-2B figures. The taxpayer then:

1. Verifies the auto-populated ITC against their own purchase register.
2. Reverses any ineligible or blocked credits under Section 17(5) (e.g., motor vehicles, club memberships, food and beverages).
3. Computes the net tax payable (Output Tax – Eligible ITC).
4. Pays the balance through the Electronic Cash Ledger using NEFT/RTGS or UPI.
5. Files the return by the 20th of the following month.

The Complete Monthly GST Compliance Cycle

The three forms work in a strict chronological sequence each month. Here is the complete workflow:

Key Differences: GSTR-2A vs GSTR-2B vs GSTR-3B

Section 16(2)(aa): Why GSTR-2B Is Now Legally Mandatory for ITC

Before the Finance Act 2021, Rule 36(4) allowed provisional ITC claims of up to 5% over what was reflected in the supplier's filed returns. The Finance Act 2021 replaced this with the much stricter Section 16(2)(aa), which states:

"The details of the invoice or debit note referred to in clause (a) have been furnished by the supplier in the statement of outward supplies and such details have been communicated to the recipient of such invoice or debit note in the manner specified under section 37."

In practice, this means that if a supplier has not uploaded an invoice in their GSTR-1 by the 13th of the month, it will not appear in your GSTR-2B, and you cannot legally claim ITC on that invoice for that month — even if you hold the physical invoice and have already paid the supplier.

This makes supplier compliance monitoring a critical part of the purchase management function. Businesses should actively chase non-compliant vendors before the 13th of each month.

How to Download GSTR-2B JSON and Import It to Tally Prime

To reconcile your purchase register against GSTR-2B, follow these steps:

1. Log into the GST Portal: Go to gst.gov.in and navigate to Services → Returns → GSTR-2B.
2. Select the Tax Period: Choose the month for which you want to download GSTR-2B (e.g., June 2026). Click Generate GSTR-2B if not already generated (only available after the 14th).
3. Download the JSON File: Click Download JSON. The portal may split large files into multiple zipped JSON parts. Download all parts.
4. Import into Tally Prime: In Tally Prime, go to Gateway of Tally → Display More Reports → GST Reports → GSTR-2B. Click Import on the right panel and select the downloaded JSON file. Tally will display the GSTR-2B invoices alongside your purchase vouchers for side-by-side comparison.
5. Reconcile and Mark: Tally Prime will auto-match invoices by GSTIN and invoice number. Unmatched invoices (present in books but absent in GSTR-2B, or vice versa) are flagged for resolution.

Monthly Filing Deadlines: A Quick Reference

Best Practices for Monthly ITC Reconciliation

• Monitor vendor compliance weekly: Do not wait until the 14th to discover that key suppliers have not filed. Use the GST portal's supplier-wise GSTR-2A view mid-month to identify non-filers and send reminders before the 13th cutoff.
• Reverse blocked credits before filing: Section 17(5) blocks ITC on motor vehicles, works contracts, food and beverages, club memberships, and personal expense items. These must be identified in your purchase register and reversed in Table 4D of GSTR-3B before filing.
• Never claim more than GSTR-2B allows: The portal marks excess ITC claims in red. Filing with such discrepancies increases audit risk and may attract demand notices under Section 73/74.
• Maintain invoice-level purchase records: The foundation of any GSTR-2B reconciliation is an accurate, invoice-level purchase register in your accounting system. Each purchase voucher must carry the correct supplier invoice number, date, GSTIN, and tax split.

Automate Purchase Invoice Entry with TrulyInvoice

The accuracy of GSTR-2B reconciliation depends entirely on the quality of your purchase data in Tally Prime. If even one vendor invoice is entered with the wrong invoice number, date, or GSTIN, the reconciliation will produce mismatches that take hours to investigate.

TrulyInvoice eliminates manual data entry errors at the source. Here is how it works:

• Upload your supplier invoice PDFs to TrulyInvoice.
• TrulyInvoice's layout-aware OCR engine reads the invoice — extracting the supplier name, GSTIN, invoice number, date, HSN codes, line-item taxable values, and CGST/SGST/IGST amounts with high accuracy.
• The extracted data is mapped to Tally Prime's F9 Purchase Voucher format and synced directly into your company data — no copy-pasting, no typing errors.
• When you download GSTR-2B and run the reconciliation in Tally, the match rate is dramatically higher because the supplier invoice numbers and GSTINs in your books exactly match what appears on the portal.

TrulyInvoice is available at a flat subscription of plans starting at ₹399/month. For businesses that process tens or hundreds of purchase invoices per month, this is the single most impactful step you can take to make your GST compliance faster and more accurate.