GST refunds that get blocked: the procedural failures that delay claims

An exporter waits six months for a GST refund that should have arrived in sixty days. A SaaS firm supplying to overseas clients has three quarters of accumulated input-tax credit sitting in the electronic credit ledger with no refund in sight. A manufacturer who applied before the last date of the relevant period gets a deficiency memo three months later saying the application was filed under the wrong category.

These are not disputes about whether the refund is owed. In every case above, the refund was legitimate. The problem was procedural. The application had a defect, a mismatch, or a missing document that the department was not only entitled to reject but required to. The money was not gone. The timeline was.

We handle GST refund work for exporters, SaaS companies with cross-border revenue, and manufacturers with inverted-duty structures. The same five procedural failures show up repeatedly. Each one is avoidable. Each one has a concrete fix.

Failure one: the LUT is in the wrong state or expired

Letter of Undertaking is the document that allows exporters to supply goods or services without paying IGST at the point of export, preserving the right to claim a refund of accumulated input credit. It sounds administrative. In practice it is the single most common reason export refund applications get returned.

Three versions of the LUT problem appear regularly. First, the LUT was filed in a prior financial year and the firm did not renew it before the export invoices were raised. The export happened in April, the LUT was valid through March. Every invoice raised after renewal lapsed is treated as a supply without a valid LUT, which means IGST should have been paid at the point of export. The refund of input credit for those invoices becomes contested.

Second, the LUT was filed in the wrong GSTIN jurisdiction. A firm operating across multiple states sometimes files the LUT in the head-office state while exports were invoiced out of a different state registration. Refund applications from the second registration have no LUT backing them.

Third, the firm exported on payment of IGST instead of under LUT, then applied for a refund of IGST paid rather than a refund of unutilised input credit. These are two different refund categories, processed differently, with different documentary requirements. Applying under the wrong category triggers an automatic deficiency memo.

The fix is straightforward: file the LUT for the new financial year in the first week of April, before any export invoice is raised. Do it in every GSTIN that exports. Maintain a calendar entry because the department does not send reminders.

Failure two: invoice data does not match across GSTR-1, GSTR-3B, and the shipping bill

A GST refund for an exporter depends on the department being able to trace a chain from the input invoices in GSTR-2A, through the output invoices in GSTR-1, to the corresponding shipping bills filed with Customs. If any number in that chain does not match exactly, the system throws an error and the refund application stalls.

The mismatches we see most often are not large. The invoice number in GSTR-1 has a slash where the shipping bill has a hyphen. The taxable value in GSTR-1 is in rupees; the invoice used a slightly different exchange-rate rounding. The shipping bill was filed before the GST invoice was uploaded to the portal, so the department's system cannot reconcile them sequentially.

These look trivial. To the refund-processing system they are hard stops.

Cleaning the data before applying

The right approach is to run a three-way reconciliation before submitting the refund application, not after getting a deficiency memo. Pull the GSTR-1 data, the shipping bill data from the ICEGATE portal, and the inward invoice data from GSTR-2A. Map every export invoice to its corresponding shipping bill. Flag every field where there is any difference, however small, including case differences in invoice numbers.

Where a mismatch can be corrected before the return period closes, correct it. Where the return period is closed, file the refund with a covering note explaining the discrepancy and attaching both documents side by side. The covering note does not guarantee approval, but it converts a blind rejection into something the processing officer can actually review.

For SaaS firms billing in foreign currency, the exchange-rate difference is predictable. Use the RBI reference rate for the invoice date and document that choice explicitly in the refund application. Consistency across invoices matters more than the specific rate used.

Failure three: incorrect or missing HSN/SAC codes

HSN codes for goods and SAC codes for services are the classification spine of GST. Refund eligibility, rate applicable to the supply, and the correct refund category all flow from getting these right. Getting them wrong is more common than it should be.

For exporters of goods, the problem is often HSN at the four-digit level in the invoice when the shipping bill requires the eight-digit code. The four-digit code is accepted for tax purposes but the Customs system requires eight digits for the shipping bill, so the two documents are never matched correctly by the department's reconciliation engine.

For SaaS and other service exporters, the SAC code applied to the invoice determines whether the supply qualifies as an export of service under Section 2(6) of the IGST Act. A wrong SAC code can mean the supply is classified as a domestic taxable service, which removes the export-of-service status and with it the entire refund entitlement.

The fix has two parts. First, build a master list of every HSN or SAC code your firm uses, validated against the GST rate schedule and, for goods exporters, the Customs Tariff heading. Second, lock this list in the invoicing system so individual users cannot override it. The classification decision should be made once, correctly, and then enforced at the point of invoice generation.

Failure four: no FIRC or missing bank realisation certificate for service exports

Export of services under GST is zero-rated, but the refund of input credit depends on demonstrating that payment for the service was received in foreign exchange. The document that proves this is the Foreign Inward Remittance Certificate issued by the exporter's bank, or a Bank Realisation Certificate for older transactions.

The FIRC problem has two variants. The first is that the FIRC was not obtained at all, or the bank issued an informal credit advice instead of the formal certificate. The department will not accept anything other than the formal document.

The second, more common variant: the FIRC is for the full contract value while the invoices raised were for monthly tranches. The department processes invoices individually, not against aggregate contract values. So a single FIRC for $120,000 does not satisfy the documentary requirement for twelve monthly invoices of $10,000 each. You need a FIRC for each remittance, or a statement from the bank mapping remittances to invoice numbers.

Some banks issue a consolidated bank statement format that the department has accepted. We have also seen the department accept a chartered-accountant certificate mapping the aggregate FIRC to individual invoices when the bank will not issue separate FIRCs. However, neither of these is guaranteed. The safest practice is to obtain a FIRC or equivalent for each remittance at the time of receipt and file it with the corresponding invoice data in the refund application.

Failure five: refund applications filed outside the two-year window or before the filing trigger

Under Section 54 of the CGST Act, a refund application must be filed within two years from the relevant date. The relevant date is not the same for all refund types. For export of goods with payment of IGST, it is the date of the shipping bill. For export without payment of IGST (i.e., under LUT), it is the end of the financial year in which the export invoice was raised. For inverted-duty refunds, it is the date of filing of GSTR-3B for the relevant period.

Firms that miscalculate the relevant date sometimes apply late and then spend months in adjudication trying to argue condonation. Condonation of delay in refund matters requires showing sufficient cause, and the department's adjudicating officers are not generous about it.

The opposite problem also occurs. Some firms apply for the LUT-export refund before the financial year ends, meaning the relevant date has not yet crystallised. The application is not invalid, but the supporting documents for invoices raised later in the same financial year cannot be included, so the refund is partial. A second application for the balance then creates reconciliation work across two refund orders.

The filing calendar we use

For export refunds under LUT, we file once per quarter, covering all export invoices from the preceding quarter, with a final year-end sweep in May to capture any invoices from the March quarter where GSTR-3B filing was late. This avoids both premature applications and the risk of letting the two-year window narrow.

For IGST-paid export refunds, we file within thirty days of the shipping bill acknowledgment. The system processes these faster and the relevant-date calculation is simpler.

For inverted-duty refunds, we file within sixty days of the GSTR-3B for the relevant period. Any longer and the accumulated credit starts to drag on working capital unnecessarily.

What a clean refund application looks like

A refund application that does not come back with a deficiency memo has five things in order before it is submitted: a valid LUT for the current year covering the relevant GSTIN, a reconciled invoice and shipping-bill data set with every field matching, correct eight-digit HSN or SAC codes on every invoice, a FIRC or bank statement mapped to each invoice for service exports, and a correctly calculated relevant date that puts the application inside the two-year window.

None of this is technically difficult. The difficulty is that these checks are not prompted by the GST portal. The portal accepts the application and either processes it or returns a deficiency memo weeks later. By then the delay has already happened.

The firms we work with that have the cleanest refund cycles have solved this with a pre-submission checklist that runs before any application is filed. The checklist is not long. Running it takes less time than responding to the first deficiency memo.