Published 12 October 2026
The purchase register and GSTR-2B describe the same purchases from two ends. The register is what the business recorded when bills arrived. GSTR-2B is what its suppliers reported, cut off on fixed dates and shaped by the business’s own actions in the Invoice Management System. They rarely agree line for line, and every line that does not agree means something different for the credit. Some differences are only timing. Some mean credit cannot be taken yet, and some mean it can never be taken. Reconciliation is the work of telling them apart before GSTR-3B is filed, not after a DRC-01C arrives.
This guide covers what a reconciliation compares, the kinds of mismatch, how IMS actions change GSTR-2B, and how a missing invoice is followed up. The mechanics of IMS and the generation of GSTR-2B are in The Invoice Management System and GSTR-2B, and the conditions for credit in Input Tax Credit: the Conditions in Section 16(2).
Why GSTR-2B is the reference
Since 1 January 2022, section 16(2)(aa) makes credit depend on the supplier having furnished the invoice or debit note and on its communication to the recipient. Rule 36(4) names the communication: no credit is availed unless the details have been furnished in GSTR-1, “as amended in FORM GSTR-1A if any”, or the IFF, and the credit has been “communicated to the registered person in FORM GSTR-2B”. GSTR-2B is therefore the ceiling on what can be claimed for a supplier-reported document. It is not proof that the credit is due. The other conditions of section 16(2), the blocks in section 17(5) and the time limit in section 16(4) still apply.
GSTR-2A, the running view of supplier filings under rule 60, is useful for tracing when a supplier filed. It is not the statement under rule 36(4).
Periods before 2022. Before 1 January 2022 credit was not tied to GSTR-2B in this way. For differences between GSTR-3B and GSTR-2A in those years, CBIC issued Circular No. 183/15/2022-GST (2017-18 and 2018-19) and Circular No. 193/05/2023-GST (1 April 2019 to 31 December 2021). Circular No. 183/15/2022-GST directs the proper officer to verify the invoice, the receipt and payment to the supplier. Where the difference for a supplier exceeds Rs 5 lakh for the year, it calls for a certificate from a chartered accountant or cost accountant that the supplies were made and the tax paid. Below that, a certificate from the supplier is called for. Circular No. 193/05/2023-GST applies the same guidelines to the later period, but from 9 October 2019 limits credit on unreported invoices to the percentage then allowed by rule 36(4): 20, 10 and 5 per cent in successive periods to 31 December 2021. Both circulars apply only to proceedings still open.
What to have ready
| Item | Where it comes from |
|---|---|
| Purchase register for the period, at document level: supplier GSTIN, document type, number and date, taxable value, tax by head, place of supply | Books |
| Goods receipt and service completion records | Books and stores records |
| The draft GSTR-2B, downloaded in Excel or JSON, with its cut-off dates | Portal, returns dashboard; cut-offs under “View Advisory” on the GSTR-2B page |
| The IMS dashboard, with pending records from earlier periods | Portal, Services > Returns > Invoice Management System |
| GSTR-2A for tracing supplier filing dates | Portal |
| Bills of entry not yet in GSTR-2B | Customs records; the portal’s search for bills of entry from ICEGATE |
| The previous period’s reconciliation, with open items carried forward | Books |
What a reconciliation compares
The fields that matter are the ones that decide whether a record is the same document. GSTN’s advisory of 18 September 2020 on its Matching Offline Tool lists the fields the tool matches on: “GSTIN, Document type, Document number, Document date, taxable value, total tax amount and tax amounts head wise”. The tool reports each record as an exact, partial or probable match, or unmatched. Any reconciliation, by the tool or by a spreadsheet, does the same thing: it pairs each register line with a GSTR-2B record, and lists what is left on each side.
Three features of GSTR-2B shape the result.
- Cut-off by filing date, not document date. A document goes into the GSTR-2B open when the supplier files it, whatever its date. The GSTR-2B FAQs give the example of an invoice dated 15 May 2021, reported in the July GSTR-1 filed on 11 August, which appears in the July GSTR-2B and not in May’s.
- Sections. GSTR-2B separates credit available (table 3, Part A), credit notes to be netted off (Part B), credit not available (table 4), the rule 37A reversal (table 5, in September only) and records rejected in IMS.
- What is not there. Imports of services, and reverse charge purchases from unregistered persons, never appear in GSTR-2B. Their credit rests on the recipient’s own documents and payment.
The kinds of mismatch, and what each means
| Mismatch | What it usually means | Effect on the claim |
|---|---|---|
| In both, matching | Supplier reported correctly | Credit may be claimed, if the other conditions are met |
| In the register, not in GSTR-2B | Supplier has not reported it, reported it late, reported it to a wrong GSTIN, or reported it as a B2C supply | No credit now (rule 36(4)). The supplier is followed up, below. Credit is taken in the period in which the record reaches GSTR-2B, within section 16(4). |
| In GSTR-2B, not in the register | Bill not yet received or booked; goods in transit; a document that is not the recipient’s | Not claimed until the goods or services are received (section 16(2)(b)). In IMS the record is kept pending or rejected, below. |
| In both, values or tax differ | Wrong rate, value or document number in GSTR-1, or a debit or credit note not reflected in one place | Credit is limited to the lower of the document and GSTR-2B, until the supplier amends. A higher GSTR-2B figure is not claimed above the document. |
| In both, wrong tax head (integrated instead of central and State, or the reverse) | Place of supply wrongly reported | The record goes to GSTR-2B as reported. Where the supplier’s GSTIN and the place of supply are in the same State and the recipient is in another, GSTR-2B shows it as “ITC Not Available”. The supplier corrects the place of supply through an amendment. |
| In “ITC Not Available”, for section 16(4) | Supplier reported the document after the recipient’s time limit | No credit. Shown in table 4(D)(2) of GSTR-3B. |
| In table 5 of the September GSTR-2B | Supplier has not filed GSTR-3B for the period by 30 September | Reverse under rule 37A by 30 November; reclaim when the supplier files. See Rule 37A. |
| A credit note in GSTR-2B not in the register | Supplier has reduced its price or tax | Credit reduces on acceptance in IMS, by the amount the recipient declares, below. |
The GSTR-2B FAQs add a caution. The “ITC Not Available” table covers only two scenarios, section 16(4) and the place-of-supply case. “There may be other scenarios for which Input Tax Credit may not be available”, and those are for the recipient to “self-assess & reverse” in GSTR-3B. Blocked credit and credit for exempt use are the main examples.
How IMS actions change GSTR-2B
The draft GSTR-2B generated on the 14th includes every record accepted, or not acted on, by then. Records with no action are “deemed accepted” (IMS FAQs). After the 14th, actions can still be changed until GSTR-3B is filed, and GSTR-2B is then recomputed. The IMS FAQs say there is no limit on the number of recomputations before filing, and that recomputing is needed for later actions to reach GSTR-3B.
What each result of the reconciliation calls for in IMS:
- Matched, and goods or services received. Accept, or leave for deemed acceptance. The record goes to “ITC Available”.
- In GSTR-2B but goods not yet received. Keep pending. A pending record stays out of GSTR-2B and on the dashboard until it is acted on or until the section 16(4) date, after which it is removed (IMS FAQs, question 21).
- Not the recipient’s document, or wrong in its details. Reject. The record goes to the “ITC Rejected” section and does not flow to GSTR-3B. Rejecting an invoice does not reduce the supplier’s tax. The supplier sees the rejection in its view of IMS and corrects the record.
- Credit notes. Since the October 2025 period, a credit note may be kept pending for one tax period only. On acceptance the recipient says whether credit is to be reduced and by how much: “No” where the credit on the original invoice was never taken, “Yes” for full reduction, or “Yes” with a lower amount for partial reduction, with a mandatory remark. Rejecting a credit note adds the tax back to the supplier’s next return. This follows the proviso to section 34(2), in force from 1 October 2025, under which a supplier’s credit note reduces its tax only if the registered recipient has reversed the credit. The detail is in the IMS guide linked above.
GSTN’s FAQ on IMS (question 31) warned, when IMS began, that an invoice of a closing year rejected in the last month before the section 16(4) date loses that credit unless the action is changed before GSTR-3B is filed. The same applies every year in October and November.
Following up a missing invoice
Where an invoice is in the register but not in GSTR-2B, the remedy lies with the supplier. What the supplier can do depends on how far its own filing has gone.
- The supplier has not filed GSTR-1 for the period. It adds the invoice before filing.
- The supplier has filed GSTR-1 but not its GSTR-3B for the period. It can add or correct the record in FORM GSTR-1A. A proviso to rule 59(1) allows this after GSTR-1 “but before filing of return in FORM GSTR-3B for the said tax period”. GSTR-1A cannot change the recipient’s GSTIN. Details added in GSTR-1A go to the recipient’s next open GSTR-2B (rule 60(7)(iia)).
- The supplier has filed GSTR-3B for the period. It reports the invoice in a later GSTR-1 or IFF, or amends a wrongly reported record in table 9A. A record reported to a wrong GSTIN is corrected by amendment in a later GSTR-1, not in GSTR-1A.
The supplier’s own window closes on 30 November after the year, or on its annual return if earlier, under the proviso to section 37(3). The recipient’s credit window under section 16(4) closes on the same date for the recipient’s year. A record that reaches GSTR-2B after the recipient’s section 16(4) date is shown as “ITC Not Available”. GSTN’s advisory of 17 October 2021 described this for 2020-21: records reported after the deadline “will not reflect as ‘ITC Available’”. A supplier who reports in November therefore leaves its customer very little time, and one who reports in December leaves none.
The supplier’s procedure is in Filing GSTR-1, and Correcting It in GSTR-1A and Correcting Mistakes in Returns.
Records rejected by mistake
Once GSTR-3B has been filed, an IMS action cannot be changed. GSTN’s advisory of 19 June 2025 sets out the remedy. The recipient asks the supplier to report the same record, unchanged, in GSTR-1A for the period or in the amendment table of a later GSTR-1 or IFF. Because the amendment tables carry only the difference, the supplier’s tax does not rise. The recipient accepts the record and recomputes GSTR-2B, and gets the credit only in the GSTR-2B of the period in which the record is re-reported. For a credit note rejected by mistake, the supplier’s liability is first added back and then reduced again, so the net effect counts once.
Time limits
| What | Limit | Provision |
|---|---|---|
| IMS actions for a period | Until GSTR-3B for that period is filed | IMS FAQs |
| Credit note kept pending | One tax period; the due date of the next GSTR-3B | GSTN advisories of September and October 2025 |
| Invoice or debit note kept pending | The section 16(4) date | IMS FAQs |
| Supplier’s correction of GSTR-1 | 30 November after the year, or annual return if earlier | Section 37(3) proviso |
| Recipient’s credit | 30 November after the year of the document, or annual return if earlier | Section 16(4) |
| DRC-01C reply | Seven days | Rule 88D |
Consequences of claiming above GSTR-2B
Credit claimed in GSTR-3B above GSTR-2B, beyond the limit recommended by the Council, triggers an intimation in Part A of FORM GST DRC-01C under rule 88D. The recipient pays the excess with interest through DRC-03, or explains the difference, within seven days. GSTN’s advisory of 6 October 2023 states that without a reply in Part B, the next GSTR-1 or IFF cannot be filed. The procedure is in Answering a DRC-01C. Credit wrongly availed and utilised carries interest under section 50(3).
What can still be put right
- Credit not claimed because a record was missing. It is claimed in the GSTR-3B of the period in which the record reaches GSTR-2B, within section 16(4).
- Credit claimed on a record that was then found wrong. It is reversed in table 4(B)(2) of a later GSTR-3B. Where the defect is cured, for example on receipt of the goods, it is reclaimed in 4(A)(5) and shown in 4(D)(1). See Reporting Credit in GSTR-3B Table 4.
- A mistaken IMS action after filing. It is cured by the supplier re-reporting the record, as above.
The routes are mapped in Correcting Mistakes in Returns and Late Returns.
The procedure in order
- Download the draft GSTR-2B and the IMS records for the period, and note the cut-off dates.
- Pair each register line with a GSTR-2B record on GSTIN, document type, number, date, value and tax by head.
- Classify every unmatched line on each side, using the table of mismatches above.
- Accept matched records for goods or services received; keep pending those not yet received; reject those that are not the recipient’s or are wrong.
- On each credit note, declare the credit to be reduced, with a remark for a partial or nil reduction.
- Recompute GSTR-2B after any change, and take the result into GSTR-3B.
- Ask suppliers to report missing invoices in GSTR-1A or a later GSTR-1, well before 30 November.
- Carry open items to the next period’s reconciliation, and answer any DRC-01C within seven days.
The next guide covers how the reconciled figures are reported in table 4 of GSTR-3B, and the two portal statements that track reversals, reclaims and reverse charge credit.