Letter of Undertaking (LUT) for GST-Free Exports: How to File

If your business exports goods or services from India, the LUT is the single most important document standing between you and a much slower, more expensive way of doing business. Filing it correctly, and on time each year, is what lets you invoice foreign clients without paying IGST first and chasing a refund later. This guide covers exactly how to file it. For the underlying distinction between zero-rated and exempt supplies and why exports fall into the zero-rated category, see our companion guide on GST on exports: zero-rated vs exempt; this post focuses purely on the LUT filing mechanics.

What Is a LUT and Why File One

A Letter of Undertaking, filed in Form GST RFD-11, is a declaration by an exporter that they will fulfil all requirements of exporting under GST without paying IGST on the export invoice. Without a LUT in place, an exporter has to pay IGST on every export invoice and then apply for a refund, a process that can take 30 to 90 days and ties up working capital that would otherwise fund operations. With a LUT, you export at 0% IGST directly, and separately claim a refund of accumulated input tax credit instead of a refund of tax you already paid.

Who Can File a LUT

Any GST-registered person intending to export goods or services, or supply to a Special Economic Zone, without paying IGST is eligible to file a LUT. There is no minimum turnover requirement. The only exclusion is a taxpayer who has been prosecuted for an offence involving tax evasion of Rs 2.5 crore or more under the CGST Act, the IGST Act, or an earlier indirect tax law; such a taxpayer must furnish a bond instead, or pay IGST and claim a refund on each shipment.

Step-by-Step: Filing Form RFD-11 on the GST Portal

1. Log in to the GST portal and navigate to Services > User Services > Furnish Letter of Undertaking (FORM GST RFD-11).
2. Select the financial year for which the LUT is being filed. The portal typically opens the window for the upcoming financial year before it starts.
3. Complete the self-declaration confirming you will comply with the conditions of the LUT: exporting within the prescribed period, and remitting the tax with interest if you fail to export as declared.
4. Fill in witness details: name, occupation, and address of two independent witnesses.
5. Submit with a Digital Signature Certificate or EVC, the same authentication method used for other GST filings.
6. Download the acknowledgment (Form GST RFD-11 with an ARN) immediately after submission; this is your proof of filing until the approval reflects on the portal.

There is no fee for filing a LUT, and no requirement to submit it on physical stamp paper when filed through the portal.

Approval Timeline: Deemed Approval in 3 Days

Once submitted, a jurisdictional officer can review and approve the LUT. In practice, most applications are never manually touched: if the officer does not act within 3 working days of submission, the system grants automatic deemed approval, and the LUT is usable immediately. This makes the process considerably faster than most other GST approvals, but exporters should still keep the acknowledgment on file, since some banks and customs processes ask for the accepted LUT copy alongside shipping documents.

Validity: One Financial Year, No Automatic Renewal

A LUT is valid strictly for the financial year in which it is filed, from April 1 to March 31, no matter when during that year it was actually submitted. There is no renewal process; a completely fresh Form RFD-11 must be filed for each new financial year. The most common operational mistake is assuming last year's LUT carries forward. It does not, and exporters who forget to file before April 1 find their early-April export invoices sitting in a grey zone with no valid LUT covering them. File the new year's LUT in March, before the current one lapses, rather than waiting until an export is ready to ship.

What Happens If You Export Without a Valid LUT

Exporting without a LUT (and without a bond) in force means you do not have authorisation to export without paying IGST. The practical consequence is that you must pay IGST on the export invoice at the applicable rate and then file a separate refund claim in Form RFD-01 for that IGST paid, a process that typically takes weeks to a few months depending on documentation and department processing. Treating an export as LUT-covered when no valid LUT exists for that period is a compliance gap that can attract a demand for the unpaid IGST plus interest if flagged in a departmental review, so exporters should confirm LUT status before invoicing, not after the shipment has gone out.

Once your LUT is filed and the export is invoiced correctly, the next step is claiming the refund of accumulated input tax credit; our guide on zero-rated exports and the RFD-01 refund process walks through that in detail. Our GST Advisory team also handles LUT filing and renewal as part of ongoing export compliance, so it never lapses unnoticed.