What is a GST LUT (Letter of Undertaking)? Form RFD-11 explained

Last updated 21 September 2026

A concrete example first

Consider a Bengaluru-based SaaS company invoicing a client in Singapore ₹8 lakh for a quarter's subscription fees. Because this is an export of services, ordinarily the company would need to charge 18% IGST on the invoice — over ₹1.4 lakh — pay it to the government, and then apply for a refund weeks or months later. With an LUT on file, the company instead raises the invoice with no IGST at all, and the ₹1.4 lakh never leaves its account in the first place. That's the entire point of an LUT.

Form RFD-11 and Rule 96A, in plain terms

Rule 96A of the CGST Rules, 2017 allows a registered person to supply goods or services for export, or to a Special Economic Zone, without paying integrated tax — provided they furnish either a bond or a Letter of Undertaking. Form RFD-11 is the specific form used to file the LUT itself, submitted on the GST portal under Services > User Services > Furnish Letter of Undertaking (LUT). Most exporters qualify for the simpler LUT route rather than a bond — see who's eligible.

What “zero-rated supply” actually means

Under Section 16 of the IGST Act, 2017, exports of goods or services and supplies to SEZ units or developers are treated as “zero-rated supplies.” This doesn't mean the supply is exempt — it means the exporter is entitled to either export without paying IGST (the LUT route) or pay IGST and then claim a refund of that tax and of related input tax credit. See our explainer on zero-rated supply.

Who typically files one

Anyone shipping goods internationally, billing an overseas client for services, or supplying an SEZ unit and wanting to avoid paying IGST upfront. This covers freelancers and SaaS founders just as much as it covers SEZ suppliers and traditional goods exporters.

This article is for general information only. For your specific situation, consult a practicing CA.