By CA Surekha Ahuja
From legal framework to utility workflow — covering the offline JSON tool, LUT compliance, GSTR-2B reconciliation, common errors and their remedies, and building an audit-proof refund file.
Effective May 2026 ·
Exports · SEZ · Inverted Duty
· Consultancy ·
Section 54(3) CGST Act · Rule 96A
|
10,000 Line items per JSON file |
25 Max files per application |
5 Duplicate validation parameters |
54(3) CGST Act — ITC refund right |
From May 2026, GST refund filing under accumulated ITC claims has become more structured, more automated, and far less forgiving of mismatch. GSTN has migrated Annexure-B for covered refund categories to a standardised offline utility that generates JSON for upload — with invoice-wise, HSN/SAC-wise reporting, duplicate validation, and GSTR-2B matching now built directly into the process. The refund right under law remains unchanged. The proof standard has become substantially stricter.
1. The Legal Foundation
Statutory
framework: Section 54(3) and Rule 96A
The
substantive right to refund of unutilised ITC arises under Section 54(3) of the
CGST Act. For zero-rated supplies without payment of tax, the operating
compliance route is Rule 96A of the CGST Rules read with the Letter of
Undertaking (LUT) in Form GST RFD-11. The formal refund application is filed in
Form RFD-01, to which Annexure-B is a mandatory statement providing an
invoice-wise summary of the claim.
Rule
96A requires the LUT to be furnished prior to export. If export services are
not paid in foreign exchange within the prescribed period, tax with interest
becomes payable — failing which the permission to export without payment of tax
may be withdrawn and recovery can follow.
LUT
timing is not a procedural afterthought. It is a legal pre-condition for the
export-without-payment route, and the new utility enforces that linkage
automatically.
|
The compliance chain — zero-rated refunds |
|
Valid
LUT →
Invoice on or after LUT date
→ Correct outward reporting in
GSTR-1 → ITC reflected in GSTR-2B →
Reconciled Annexure-B → Refund application in RFD-01. Any broken link weakens the entire claim. |
2. What Changed in Annexure-B from May 2026
From PDF annexure to structured offline utility
Until recently, taxpayers prepared Annexure-B in a workbook and submitted a PDF copy alongside the refund application. The adjudicating officer then verified and evaluated its correctness manually. That process is now closed.
From May 2026, Annexure-B cannot be filed manually. The GST portal has implemented a mandatory offline utility — a tool that taxpayers use to enter invoice details, compute the eligible refund amount, and generate a structured JSON file for upload. The portal validates the data on receipt. The utility enforces structure, consistency, and completeness that a PDF could not.
Core technical requirements
→ Invoice-wise data.
The utility requires granular,
invoice-by-invoice inward supply data — not a loose summary format.
→ HSN/SAC-wise classification. Each
entry must carry the correct HSN or SAC code for the supply. Codes must be 4,
6, or 8 digits. Codes beginning with '0' or mismatched to the nature of supply
are rejected.
→ Category segregation.
Inputs, input services, and
capital goods must be classified separately. Eligible and ineligible ITC must
be bifurcated correctly. Blocked credit under Section 17(5) must be excluded.
→ Splitting of mixed invoices. Where
one invoice contains multiple HSN/SAC codes or mixed categories, it must be
split into separate line items with proportionate allocation of tax and value.
→ Duplicate validation.
The portal validates each entry
across five parameters simultaneously: supplier GSTIN, invoice number, invoice
date, category of input supply, and HSN/SAC code. Identical entries under the
same parameters are rejected outright — there is no override.
→ GSTR-2B validation.
For invoices from November 2024
onward, mismatches appear in the invalid documents report. Older periods may
show a generic non-validation message, which should not be treated as an error.
Reconciliation must happen before filing, not after.
→ File capacity. The utility accepts up to 10,000 line items per file and
25 files per refund application. Remaining invoices may be submitted as PDF
supporting documents.
→ ITC reversals. ITC reversed under GSTR-3B must be reported in Annexure-B
only as per the reversal made in Table 4B(i) or Table 4B(ii) of GSTR-3B. No
other reversal basis is accepted.
→ Upload sequence. Annexure-B must be uploaded after Statement 3 (for ITC
refunds on exports against LUT) or after Statement 1A (for refunds under
Inverted Duty Structure), as applicable. Uploading out of sequence will cause
processing errors.
→ Automated credit utilisation order. Once the utility is validated, the portal automatically computes the order of utilisation of CGST, SGST, and IGST credit under Section 54 of the CGST Act read with Rule 89 and Circular No. 125/44/2019.
3. Using the Offline Utility: Step-by-Step
Five steps
from download to submission
The
process must be followed in the correct sequence. Skipping or reordering steps
— particularly generating the JSON before validation — is a common cause of
avoidable errors.
Step 1 Download
the latest version
Navigate
to the GST portal (www.gst.gov.in) → Downloads → Offline Tools → Refund Offline
Tool. Always download the most recent version. Using an outdated utility is one
of the most common causes of filing errors. Before opening the new download,
ensure that any previously open version of the utility is fully closed —
running two versions simultaneously causes issues with copy-paste and
validation functionality.
Step 2 Enter
invoice details
Open
the utility and enter: GSTIN, tax period, invoice numbers, invoice dates,
taxable values, and applicable tax amounts (IGST, CGST, SGST). All entries must
match exactly with what was reported in GSTR-1 and GSTR-3B returns.
|
Data entry discipline |
|
· Date format must be dd-mm-yyyy only.
The system sometimes changes this automatically — verify before proceeding.
· Decimal values must be restricted to
2 digits. · Enter tax values only in
applicable columns. For interstate supplies where IGST applies, leave CGST
and SGST blank. Use F2 + Enter in the Cess field to populate the Total Tax
column. · For copy-paste: use
right-click paste, not Ctrl+V. Ensure the pasted value matches the exact
dropdown option — any leading or trailing space causes a validation error. Do
not paste into frozen or protected fields. |
Step 3 Validate
the data
Use
the in-built Validate button within the utility before generating the file. The
utility flags missing fields, format errors, and obvious mismatches. Resolve
all errors shown at this stage. Do not proceed to file generation until
validation passes cleanly.
Step 4 Generate
the JSON file
Once
validation is successful, use the Generate File option to produce the JSON. Do
not open, edit, or rename the JSON file after generation — any modification
breaks the portal's ability to read it. If corrections are needed, make them in
the utility, revalidate, and generate a fresh JSON.
Step 5 Upload via
Form RFD-01
Upload the JSON file on the GST portal while filing Form RFD-01. Confirm the upload sequence — Statement 3 or Statement 1A must be uploaded first. After upload, verify that all invoices appear correctly in the portal view before submitting the refund application.
4. Common Errors: Causes and Remedies
Ten errors
practitioners encounter most frequently
The
table below covers every significant error category encountered in the
Annexure-B utility, their technical cause, and the correct remedy. In all
cases, the governing principle is the same: correct the underlying data in the
utility, revalidate, generate a fresh JSON, and refile. Never attempt to edit
the JSON file directly.
|
Error
message |
What it
means |
How to fix
it |
|
Duplicate
data validation error |
Hidden spaces,
copied values, or formatting issues in the utility. |
Re-enter data
carefully. Avoid copy-paste from external sources. Remove extra spaces before
generating the JSON. Use right-click paste rather than Ctrl+V. |
|
Document
date cannot be greater than return period |
The tax period
selected does not match the data available on the portal, or the refund
period is outside the permissible range. |
Verify that
the refund period is correct and falls within the allowed window. Correct the
invoice date or increase the selected return period. |
|
JSON has no
data / at least one invoice should be present |
The portal
cannot read the generated JSON file properly. |
Check that
invoice details are correctly saved in the utility. Regenerate the JSON file
before uploading. Do not manually edit or rename the JSON file after
generation. |
|
GSTIN of
supplier not matching with GSTR-2B |
Wrong supplier
selected, or extra spaces or hidden characters in the GSTIN field. |
Verify the
supplier GSTIN and all invoice details against GSTR-2B. Re-enter manually if
copy-paste introduced hidden characters. |
|
Invoice not
appearing after upload |
Incorrect
mapping or incomplete entry in the offline utility. |
Verify that
the invoice is entered in the correct section and all mandatory fields are
completed. Re-generate and re-upload. |
|
Wrong ITC
classification |
Eligible and
ineligible ITC not bifurcated correctly. |
Recheck the
ITC classification. Ensure blocked credit under Section 17(5) is excluded.
Confirm that reversals match what was reported in GSTR-3B Table 4B(i) or
4B(ii). |
|
GSTR-2B
mismatch |
Invoice period
or credit mapping is incorrect. |
Match the
invoice with the correct GSTR-2B period before generating the file. Classify
the mismatch — supplier-side, period, duplicate, or internal — and resolve
before refiling. |
|
Utility
version mismatch |
An outdated
version of the offline utility is being used, which may not be compatible
with the current portal. |
Always
download the latest version from the GST portal (Downloads > Offline Tools
> Refund Offline Tool). Delete old versions to avoid confusion. |
|
HSN/SAC
code invalid |
Code does not
match the nature of goods or services, or the code begins with '0'. |
Ensure HSN/SAC
code matches the supply type. Remove any leading zero. HSN codes must be 4,
6, or 8 digits only. |
|
Incorrect
demand or order reference |
Demand ID,
order number, or refund-linked balance is not aligned with portal records. |
Re-verify the
selected demand, the relevant order, and the amount eligible for refund
before submission. |
5. GSTR-2B Reconciliation Before Filing
Reconcile
first, generate JSON second, file third
Refund
filing has become a reconciliation-led compliance exercise. A refund claim that
is not reconciled at source is vulnerable even when the underlying supply is
entirely genuine. The new utility makes this explicit — mismatches surface
during validation and block generation of a clean JSON.
Classifying
the mismatch
Before
reacting to a rejection or validation error, classify the mismatch precisely.
The category determines the remedy:
→ Supplier-side non-reporting: The
supplier has not filed or has filed the relevant outward supply incorrectly.
Request correction and check the updated GSTR-2B in the next GSTR-1 cycle.
→ Wrong GSTIN or invoice number: Internal
data entry error. Correct in the utility, revalidate, regenerate.
→ Wrong period: Invoice matched to the incorrect GSTR-2B period. Identify
the correct period and remap.
→ Duplicate entry: The same invoice entered more than once across the five
validation parameters. Remove the duplicate from the utility.
→ Blocked credit under Section 17(5): Credit
claimed that should have been excluded. Remove and document in the blocked
credit note.
→ Classification error:
Wrong category assigned in the
utility — input vs input service vs capital goods. Correct the category
mapping.
|
Not every mismatch is fatal |
|
Supplier-side
errors can often be corrected in the next GSTR-1 cycle and the refund refiled
or defended thereafter. The critical requirement is that the mismatch is
identified, documented with a clear reconciliation note, and resolved
proactively — not explained vaguely after rejection. A proactive
reconciliation note filed alongside the refund is far stronger than a
post-rejection defence. |
6. LUT Compliance and Consultancy Export Risk
Delayed LUT:
the exposure and the correct response
For
consultancy and professional services, there is no goods movement — the primary
compliance issues are service date, invoice date, and LUT timing. If an invoice
was raised before LUT filing, the correct professional response is not to
backdate the invoice but to preserve the actual chronology and evaluate lawful
remedies.
The
safest principle throughout is factual accuracy: keep the real invoice date,
keep the real LUT date, and resolve the exposure through lawful tax treatment —
not by altering the documentary trail.
|
Worked Example — The April Invoice / May LUT
Problem |
|
A
consultancy firm issues an export-service invoice on 20 April 2026 for
strategic advisory services rendered to a foreign client. The LUT for FY
2026-27 is filed on 15 May 2026. The invoice pre-dates the LUT by 25
days and is included in an Annexure-B refund claim. The firm is considering
changing the invoice date to 16 May 2026 to bring it within LUT cover. |
|
Do not change the
date. Leave the invoice at 20 April 2026. Evaluate whether
IGST must be paid with interest for the pre-LUT period. Changing the date
creates a four-way mismatch across books, GSTR-1, GSTR-2B, and Annexure-B —
the very data sources the new utility cross-validates simultaneously. The
risk of manipulation exceeds the risk of honest regularisation. |
If
LUT was filed in May 2026 and consultancy invoices were raised in April 2026
without payment of tax, the April period may not be fully protected by Rule
96A. In that scenario, the question to assess is whether voluntary IGST payment
with interest is safer than advancing a weak retrospective argument.
|
Critical rule — do not manipulate dates |
|
The
Annexure-B utility cross-validates four independent data sources
simultaneously: books of account, GSTR-1, GSTR-2B, and the refund annexure.
Any artificial date correction creates mismatches that an assessing officer
can identify across all four. The risk of manipulation almost always exceeds
the risk of honest regularisation. |
Credit and
debit notes: purpose and limits
Credit
and debit notes exist for genuine adjustments in supply value, quantity, or tax
— not as devices to alter invoice dates or create retrospective LUT coverage.
Each note must reference the original invoice, state the reason for adjustment,
and document the tax effect clearly.
The governing test: ask whether there is a genuine commercial or tax adjustment that warrants the note. If yes, proceed with proper documentation and maintain a reconciliation note showing the adjustment, the tax effect, and the reporting period. If the primary purpose is to alter a date, the note is not a legitimate remedy and creates additional audit exposure.
7. Building an Audit-Ready Refund File
Assemble the
file as if audit begins on the day of filing
A
well-assembled refund file reduces adjudication time, supports the claim at the
first instance, and provides a complete defence if the matter is questioned
later. The minimum documentation set divides into two tiers.
Core documents
— all refund categories
→ Tax invoices — all inward supplies in the claim
→ Purchase register — reconciled to Annexure-B
→ GSTR-2B extract — period-wise, with reconciliation note
→ GSTR-3B working — showing ITC claimed, reversed, and net
eligible
→ Refund calculation — formula-based, traceable to inputs
→ Blocked credit note — Section 17(5) exclusions documented
→ Reversal note — Rule 42/43 proportionate reversals with
working
→ Annexure-B JSON and portal acknowledgment — filed version
Additional
documents — exporters and consultancy service providers
→ LUT acknowledgment — Form GST RFD-11, pre-export date
confirmed
→ Contract or engagement letter — establishing export
status and service scope
→ Deliverable trail — reports, software, correspondence
establishing performance
→ Foreign exchange realization — FIRC or bank certificates
covering all invoices
Where invoices have been split, credits excluded as blocked or ineligible, or reversals applied, add a short explanatory note showing how the treatment flows through books, GSTR-1, GSTR-2B, and the refund annexure consistently. Consistency across all four sources is the strongest form of audit defence.
8. Zero-Rated vs Inverted Duty: A Structural
Distinction
Different in
law, logic, formula, and documentation
These
two refund categories are frequently conflated, and that conflation causes
errors in calculation, legal positioning, and documentation. They differ at the
root. Never apply zero-rated refund logic to an inverted duty claim, or vice
versa.
|
Parameter |
Zero-rated
supply refund |
Inverted
duty refund |
|
Basis |
Export / SEZ
supply — policy: exports carry no domestic tax burden |
Input tax
rate higher than output tax rate — structural ITC accumulation |
|
Legal
anchor |
Section 16,
IGST Act · Rule 96A CGST Rules |
Section
54(3)(ii) CGST Act · Rule 89(5) CGST Rules |
|
Key
pre-condition |
Valid LUT
before export; foreign exchange realization |
Rate
differential on inputs vs outputs — no LUT requirement |
|
Formula
basis |
ITC on
inputs, input services, capital goods attributable to exports |
Narrower
formula; input services excluded per VKC Footsteps (SC) |
|
Primary
risk |
LUT timing,
export realization, GSTR-2B mismatch |
Formula
computation, input service inclusion errors, rate classification |
|
Documentation
priority |
LUT,
contract, deliverables, FIRC, GSTR-2B reconciliation |
Rate
structure analysis, input-output mapping, refund formula working |
The Supreme Court's ruling in VKC Footsteps India Pvt. Ltd. v. Union of India upheld the exclusion of input services from the Rule 89(5) formula and is directly relevant to all inverted duty refund claims. Applying the broader zero-rated formula to an inverted duty claim is a calculation error that will survive scrutiny only until the assessing officer checks the formula basis.
9. Frequently Asked Questions
Questions practitioners ask most
Can invoice dates be changed on the GST portal because LUT was filed late?
No. The invoice should reflect the actual transaction date. Backdating to fit LUT creates audit, return, and refund mismatch risk across four independently cross-validated data sources — books, GSTR-1, GSTR-2B, and Annexure-B.
What is the best remedy if LUT was filed after consultancy services were invoiced?
File LUT immediately for the current year and all future zero-rated supplies. Preserve the actual invoice trail without alteration. Assess on the facts whether the pre-LUT period must be treated as taxable, and consider voluntary IGST payment with interest if the exposure is significant or audit risk is elevated.
How should refund rejections due to GSTR-2B mismatch be handled?
Classify the mismatch first — supplier-side, period, duplicate, blocked credit, or internal error. Correct the underlying data or request supplier correction in the next GSTR-1 cycle. Regenerate the Annexure-B JSON from clean data and refile with a reconciliation note. If a deficiency memo has been issued, assemble the full documentary defence before responding.
What documents are essential for audit?
Invoices, purchase register reconciled to Annexure-B, GSTR-2B extract with reconciliation note, GSTR-3B working, refund calculation, blocked credit note, reversal note, Annexure-B JSON with acknowledgment, LUT acknowledgment, contract or engagement letter, deliverable trail, and foreign exchange realization certificates.
What specifically changed in Annexure-B from May 2026?
Filing moved from a PDF annexure prepared manually to an offline utility generating a structured JSON file uploaded to the portal. The utility now enforces invoice-wise and HSN/SAC-wise reporting with category segregation, duplicate controls across five parameters, GSTR-2B validation, reversal treatment, and file limits of 10,000 line items per file and 25 files per application.
Are inverted duty and zero-rated refunds the same?
No. Zero-rated refunds are export or SEZ linked and require LUT compliance and foreign exchange realization. Inverted duty refunds arise from structural accumulation where input tax rates exceed output tax rates — a different legal basis, different formula under Rule 89(5), and different documentation requirements. The VKC Footsteps Supreme Court ruling specifically excludes input services from the inverted duty formula.
Can credit or debit notes be used to fix invoice date issues?
Only if there is a genuine underlying commercial or tax adjustment. A credit or debit note must not be used as a device to backdate a transaction or create retrospective LUT coverage — that misuse creates additional audit risk and does not cure the original timing exposure.
Is every GSTR-2B mismatch fatal to a refund claim?
No. Many mismatches are curable — supplier-side errors can be corrected in the next GSTR-1 cycle and the refund refiled or defended thereafter. What matters is that the mismatch is identified, documented with a clear reconciliation note, and resolved proactively rather than explained vaguely after rejection.
What are the most common utility data entry mistakes?
Using an outdated version of the utility; copy-pasting data with hidden spaces or using Ctrl+V instead of right-click paste; entering values in the wrong tax column (e.g. CGST/SGST on an interstate supply); using incorrect date format (must be dd-mm-yyyy); and manually editing or renaming the JSON file after generation.
Can the refund amount be reduced from the utility's automated calculation?
Yes. Once the utility validates and computes the eligible refund automatically, taxpayers may manually reduce the Net ITC figure to arrive at a lower refund amount if appropriate. The portal's automated utilisation order of CGST, SGST, and IGST credit cannot be overridden — it follows Section 54 of the CGST Act and Rule 89.
Concluding Principle
Evidence
discipline is now the core of refund compliance
The
new GST refund framework demands structured invoice data, GSTR-2B validation,
reversal reporting, and duplicate-proof filing — while LUT compliance remains a
hard pre-condition for zero-rated supplies, and utility discipline is the first
line of defence against processing errors. The safest professional strategy is
factual accuracy first, tax treatment second, and documentation throughout.
|
Keep the real invoice date |
File LUT on time |
Reconcile GSTR-2B before filing |
Use notes for genuine adjustments only |
