GST on Exports Demystified: Zero-Rated Supply, LUT, and ITC Refunds Explained 

Exports aren't supposed to be taxed. That's the whole idea behind GST's export framework. Yet talk to almost any exporter in Pune, Surat, or Bengaluru and you'll hear the same complaints — money stuck in refund applications, an LUT deadline nearly missed, or confusion about why a shipment suddenly needed IGST when last year's didn't. 

None of this is because the law is unclear about intent. Exports are meant to be tax-free. The trouble shows up in the mechanics — the filings, timelines, and paperwork that stand between "exports are zero-rated" and actually seeing that money back in your account. This post walks through the three things that decide whether your export compliance runs smoothly: zero-rated supply, the Letter of Undertaking (LUT), and refunds of accumulated Input Tax Credit (ITC). 

Why This Matters Right Now 

Two things are pushing this up the priority list for exporters. Tax authorities have tightened system-based matching — your GSTR-1, GSTR-3B, shipping bill data, and bank realisation records are now cross-checked more closely than before, so small documentation gaps that used to go unnoticed are more likely to surface as a query or a notice. And separately, for any business with meaningful export volume, unrefunded ITC is money that should be doing something else — funding the next order, covering payroll, keeping the business moving. Getting these three areas right isn't just about ticking compliance boxes; it directly affects how much working capital you have on hand. 

1. Zero-Rated Supply: What It Actually Means 

Section 16 of the IGST Act, 2017 classifies exports of goods and services — along with supplies to Special Economic Zone units or developers — as zero-rated supplies. It's worth pausing on this, because "zero-rated" and "exempt" get used interchangeably in casual conversation, and they aren't the same thing. 

An exempt supply carries no GST, but you also lose the credit on whatever tax you paid on your inputs — that cost just gets absorbed. A zero-rated supply is taxed at 0%, and you still get to claim credit on your inputs, with the option of getting that credit back as cash. The whole point is to stop Indian exports from carrying any hidden domestic tax cost, which keeps them competitively priced abroad. 

Take a garment exporter in Pune who buys fabric and trims locally, paying GST on those purchases, then ships finished garments to a buyer in Germany. The export itself has no GST on it. But the tax already paid on the fabric doesn't vanish — it sits as ITC that can either offset other GST liability or come back as a refund. 

Exporters have two ways to actually get this benefit: 

Most regular exporters go with the first option, since it means never parking cash with the government in the first place. Which brings us to the LUT. 

2. The LUT: What Lets You Skip IGST at the Border 

A Letter of Undertaking, filed as Form GST RFD-11 on the GST portal, is essentially your promise to the department that you'll meet your export obligations — mainly, bringing in your export proceeds as convertible foreign exchange within the allowed window (roughly three months for goods, one year for services, from the invoice date, with extensions possible). Filing it is what lets you invoice and ship without IGST under Rule 96A. 

A handful of things about LUTs catch even seasoned exporters off guard: 

Say a Bengaluru-based IT services firm is billing a US client for development work. Before that invoice goes out, the firm needs its LUT for the year accepted — otherwise the invoice is treated as a taxable export requiring IGST, an entirely avoidable outflow. Filing the LUT itself is quick: log in to the portal, go to Services > User Services > Furnish Letter of Undertaking, pick the financial year, complete the declarations, and submit using DSC or EVC. Once it's through, note the ARN and put it on every export invoice from that point on — it's what ties your invoices back to a valid LUT if anyone ever asks. 

3. Getting the ITC Refund Back 

This is where most of the frustration actually lives, because it's the step where cash is supposed to return — and where a documentation slip costs weeks of delay. 

The refund of accumulated ITC is claimed through Form GST RFD-01 under Section 54 of the CGST Act and Rule 89. It isn't simply "whatever ITC balance you're sitting on" — it's calculated using a formula under Rule 89(4): 

Refund Amount = (Turnover of Zero-Rated Supply ÷ Adjusted Total Turnover) × Net ITC 

Net ITC here means the credit availed during the period, minus anything reversed, and Adjusted Total Turnover leaves out exempt supplies and a few other exclusions. In practice, this means your refund scales with how much of your business is actually export-driven, not just the raw credit sitting in your ledger. 

Once RFD-01 goes in — along with GSTR-1, GSTR-3B, shipping bill or export manifest data for goods, and BRC/FIRC (bank realisation or foreign inward remittance certificates) for services — the process generally runs like this: 

A machine parts exporter filing clean, well-matched invoice and shipping bill data will often see the 90% provisional refund land within days. The final 10% follows once the officer confirms nothing's mismatched between the declared invoices and the shipping bill or bank realisation records. And that's usually where things go wrong — not because of the law, but because a shipping bill value doesn't tie back to the invoice, an FIRC wasn't uploaded, or GSTR-1 and GSTR-3B numbers don't reconcile. With scrutiny tighter now than a couple of years ago, reconciling these records before filing, rather than fixing them after a deficiency memo shows up, is probably the single most useful habit an exporter can build. 

Key Takeaways 

Exports are zero-rated, not exempt — you keep the right to claim and recover input credit, unlike exempt supplies where that credit disappears. An LUT needs to be filed fresh every financial year and doesn't cover invoices raised before it's accepted. ITC refunds follow a defined formula and a structured timeline — RFD-01, a 90% provisional payout, then a final order within 60 days, with interest owed if that's breached. And the single biggest reason refunds get stuck isn't the law itself, but mismatched paperwork across invoices, shipping bills, and GST returns. 

Where to Go From Here 

The broad framework here holds steady, but the procedural details — portal steps, reconciliation checks, documentation requirements — do shift through notifications and circulars over time. How this applies to your specific export mix or documentation gaps is worth checking with a professional rather than assuming it's identical for every business.