Letter of Undertaking (LUT) in GST – Meaning, Format, and Filing Process (

LUT full form: Letter of Undertaking. A Letter of Undertaking (LUT) is a declaration submitted by GST-registered exporters that enables them to export goods or services without paying Integrated GST (IGST) upfront. Exporters can file the LUT online through Form GST RFD-11 as per Rule 96A of the CGST Rules. Once approved, the LUT remains valid for the entire financial year.

Instead of paying the IGST and later applying for refunds, businesses can instead apply for an LUT, to streamline their cash flow and avoid delays in the business operations. It is especially beneficial for service providers and frequent exporters. But not everyone qualifies, and missing deadlines or filing errors can result in more harm than good.

In this article, we break down everything you need to know about LUT—what it is, who can file it, what documents are needed, and how to submit it online. Let’s get started.

• A Letter of Undertaking or an “LUT” allows exporters to export goods or services without having to pay IGST first, according to the GST rules in India. LUT is filed using Form GST RFD-11. Its benefits include improving cash flow and ease of trade for exporters, along with compliance to GST rules.

• To file for an LUT, exporters must be GST-registered, have no record of tax defaults, and not be prosecuted for tax evasion over ₹2.5 crore. These exporters can sign and submit the LUT annually via the GST portal and gain tax benefits.

• An LUT is valid for one financial year, and must be renewed at the beginning of each year. Missing this window or submitting incorrect details during form submission can delay shipments and disrupt cash flow. With timely renewal, export operations run smoothly.

LUT meaning in GST is a legal declaration where the exporter undertakes to fulfil all export obligations like timely export, foreign exchange realisation, and tax compliance without paying IGST upfront. In other words, LUT means the exporter gives a formal promise to the government that export conditions will be met, in exchange for being allowed to ship without an upfront tax payment.

LUT is a legal assurance that the exporter will meet all conditions related to the supply, including timely export and tax compliance.

In practical terms, it helps businesses preserve working capital. This is by eliminating the payments towards IGST before the export process.

A Letter of Undertaking (LUT) is required for Indian exporters to send goods or services abroad without paying IGST upfront. Here are the five specific reasons why exporters choose to file one:

1. Avoid IGST on exports: Filing LUT saves approximately 18% upfront tax on every shipment, which can be a significant sum for high-frequency exporters.
2. Eliminate refund-claim delays: On the IGST-paid route, refunds can take 6+ months. LUT eliminates the need to claim refunds entirely.
3. Preserve working capital: For SMEs and service exporters, not tying up capital in tax payments means more funds available for operations and growth.
4. Streamline export logistics: There’s no need to track or claim ITC on IGST paid. Thus, the compliance footprint shrinks a lot.
5. Required for SEZ supplies: Supplies to Special Economic Zone (SEZ) units are zero-rated under GST and require LUT in exactly the same way as exports.

With the introduction of the LUT mechanism under GST, the government simplified the export compliance process. With its importance clear, the next question is: who can actually file a LUT?

To file an LUT under GST, an exporter must be a registered taxpayer, should not have a history of defaults or pending dues, and have the LUT signed by relevant, authorized personnel. Meeting all eligibility conditions ensures smooth approval and uninterrupted export operations.

Here are the conditions that exporters have to meet, in order to file for LUT:

• Exporter should fill the LUT for exporting goods or services either outside of within India, or under Special Economic Zones (SEZs)
• Exporter as well as the goods and service should be registered under the GST act
• Exporter should not have been prosecuted under CGST or IGST Acts for tax evasion exceeding ₹2.5 crore
• The LUT must be authorized by relevant personnel and supplied on the exporter’s letterhead.
• Exporter should have no pending GST dues or previous instances of defaults

Note: LUT can be filed by any GST-registered exporter regardless of turnover size. There is no minimum or maximum turnover limit for LUT eligibility. However, service exporters with annual turnover below ₹20 lakh (₹10 lakh in special-category states) are not mandatorily required to register for GST. If unregistered, no LUT is needed because no GST liability arises. If a service exporter chooses to register voluntarily, which many do because foreign clients prefer GST-registered invoices, then filing LUT becomes mandatory to claim zero-rated supply.

CGST Rules(2017) state that an individual can provide LUT to export goods or services, without paying integrated tax, only if they meet the eligibility criteria. Once eligibility is confirmed, businesses can tap into the full benefits that come with a valid LUT.

The benefits of filing a Letter of Undertaking (LUT) include the ability to export goods or services without paying IGST upfront. It creates better cash flow, avoids refund delays, speeds up logistics, and helps exports run smoothly by lowering tax and paperwork hassles.

Filing an LUT unlocks several benefits for exporters. Some of these are listed below:

1. Tax Exemption

Exporters can avoid paying the IGST at the time of export, bypassing the immediate need for refunds. This can help save both time and effort.

2. Faster logistics

Building on the previous point, exporters benefit by freeing up time and resources to focus on business activities, and provide faster logistics in their export process.

3. Cash flow efficiency

Exporters free up working capital for their operations by not having to pay taxes upfront. This cash flow also supports the ability to offer competitive pricing in the market.

4. Simple renewal process

LUT is valid for one financial year after filing and is easily renewable. This lets exporters enjoy LUT benefits for a prolonged duration.

For high-frequency exporters, filing an LUT helps avoid cash crunches and keeps business operations running smoothly. 

To claim these benefits, however, you’ll need to have the right documents ready. We will look at these in the next section.

To file an LUT under GST, exporters will need documents including a GST registration certificate, PAN ID, IEC certificate, a signed LUT request letter, authorized signatory details, KYC documents, a cancelled cheque, previous LUT (if any), and a valid DSC or EVC for online submission.

When filing LUT, the GST portal requires specific documents to support the LUT application. Here's what you will need for the registration process:

• GST Registration Certificate. It confirms your business is registered and eligible to file LUT. 
• PAN Card of the company, which is used by the GST portal to validate exporter identity against the tax database. 
• IEC / Importer Exporter Code Certificate that confirms the exporter holds a valid IEC from DGFT, which is mandatory for all cross-border trade in India. 
• Letter signed by authorised person requesting LUT. It’s a formal request on company letterhead authorising the filing. 
• Authorised signatory details and KYC. It establishes who is legally authorised to commit the business to the LUT obligations)
• Cancelled cheque from the company’s bank account. It verifies the bank account linked to the business for any GST-related transactions. 
• Previous LUT copy (if applicable). It’s required for renewal only. New applicants skip this step. 
• Digital Signature Certificate (DSC) or Electronic Verification Code (EVC). It’s mandatory for authentication. DSC is required for companies and LLPs and EVC is acceptable for proprietors and partnerships)

Registering for the LUT lets you file for it using the GST RFD-11 form. Once these documents are in place, the actual filing process is fairly straightforward.

Common mistakes in LUT filing are leaving form fields incomplete, failing to renew the LUT at the start of the financial year, and missing export timelines. These issues can delay approval, affect compliance, or lead to unwanted IGST payments on exports.

Next, mistakes in LUT filing can lead to delays, penalties, or even the need to pay IGST. Here are pitfalls to watch out for.

To file an LUT online, log in to the GST portal, navigate to Services > User Services > Furnish LUT, select the financial year, upload documents, complete declarations, add witness details, and submit using DSC or EVC. An ARN is generated upon submission.

Here's how the filing process works:

1. Login: Visit the GST portal and log in.
2. Navigation: Go to Services > User Services > Furnish Letter of Undertaking (LUT).
3. Select Year: Choose the financial year for which you're applying.
4. Upload: If you’ve filed an LUT previously, upload a scanned copy.
5. Self-declaration: Tick all declaration boxes stating your commitment to the following:

• Export within 3 months from date of issue
• Abide by provisions of the GST Act
• Pay IGST plus eighteen percent interest per annum, from date of invoice till the date of payment
• Witness Details: Enter names, occupations, and addresses of two independent witnesses.

1. Place and Save: Enter place of filing, and the name and place of the authorized signatory > Click SAVE. Preview the form to check that all details have been filled correctly.
2. Sign and Submit:

• Use DSC (mandatory for companies/LLPs) or EVC (for proprietors, partnerships).
• An ARN (Application Reference Number) is generated on successful submission.

Important: The ARN is generated immediately and the LUT is deemed approved without any manual intervention, per GSTN Circular 40/14/2018-GST. You do not need to wait for an officer to review or approve your LUT. The moment the ARN appears on screen, your LUT is in force. Take a screenshot of the ARN confirmation page for your records.

You can check previously submitted LUTs from User Services > View my submitted LUTs. Filing is only valid when signed by the correct authority, so let’s look at who that is.

The LUT must be signed by an authorized signatory, who is responsible for filing the verification. This includes: proprietor, managing director, working partner, company secretary, or any person authorised by the board/partner. They can use either a DSC or an EVC, as mentioned above, to finish the filing properly.

LUT renewal is required at the start of each financial year, as it remains valid for one year. To renew LUT, exporters must log in to the GST portal, select the new year, upload the previous year’s LUT, fill out declarations, and submit using DSC or EVC for approval.

Here's a step by step process to apply for LUT renewal at the beginning of each financial year.

1. Login to the GST Portal

Visit the GST portal and sign in with your credentials.

2. Navigate to LUT Section

Click on Services > User Services > Furnish Letter of Undertaking.

3. Select Year & Upload Previous LUT

Choose the relevant financial year and upload the previous LUT (PDF/JPEG under 2MB).

4. Fill Out Declarations & Witness Details

Tick all three declaration checkboxes, enter details for two witnesses and the authorized signatory.

5. Save, Preview & Submit

Enter the place of filing, click Save, Preview, and then file using DSC or EVC.

Note: The LUT deadline for FY 2026-27 was 31 March 2026.

Some more best practices include ensuring that all previous export obligations have been fulfilled. Remember to keep updated contact details to receive ARN and alerts from the GST portal.

What if you miss the LUT deadline?

Missing the 31 March deadline does not mean you’re stuck, but it does have a cost:

• Any exports made between 1 April and the date you file LUT must follow the IGST-paid route. You will pay 18% IGST on those invoices.
• You can claim a refund of IGST paid on those exports via Form RFD-01 (the standard refund route, typically 3-6 months).
• There is no penalty for filing LUT late. The ARN is generated within minutes and the LUT becomes effective immediately from the filing date.
• Once the LUT is filed, exports from that date onwards are back on the zero-IGST route.

Are there any charges for LUT filing or renewal?

There is no government fee for filing or renewing LUT. The entire process is free on the GST portal and takes about 10 minutes. Some third-party CA or consultancy services charge ₹500-2,000 to file LUT on your behalf, but you can complete the process yourself at zero cost by following the steps above. The only requirement is a valid DSC or EVC for authentication.

LUT is a fiscal-year-bound instrument. Here are the key dates to put in your calendar:

LUT is valid for exactly one financial year. You cannot file a multi-year LUT, and you cannot carry forward an unused LUT.

When you file LUT successfully on the GST portal, the system generates a unique Acknowledgement Reference Number (ARN), this is what people commonly refer to as the LUT number.

Structure of the LUT number (ARN)

The ARN is a 15-character alphanumeric string in the format ADXXMMYYYYNNNN. For example, AD0703240012345 decodes as follows:

AD: acknowledgement prefix

07: state code (07 = Delhi; 27 = Maharashtra; 29 = Karnataka, etc.)

03: month of filing (March)

2024: year of filing

0012345: unique sequence number generated by the portal

Note: Format conventions may update over time. Always verify against the actual ARN generated on your GSTN portal.

Where to find your LUT number

The LUT number (ARN) appears on the acknowledgement screen immediately after submission. You can also retrieve it at any time from: GST portal → Services → User Services → View Submitted LUTs.

ARN vs LUT number vs LUT certificate

ARN: the filing acknowledgement generated by the portal at submission.

LUT number: the same ARN, used on export invoices and shipping bills to reference the active LUT.

LUT certificate: the printable copy of the approved LUT, downloadable from the GST portal.

Where to use the LUT number

Quote the LUT number on every export invoice issued during the LUT’s validity period (1 April to 31 March), on shipping bills filed with customs, and in any GST refund applications that reference zero-rated supplies.

The official LUT format is prescribed under Form GST RFD-11, Rule 96A of CGST Rules 2017. While the form is filed online on the GST portal, understanding the structure helps you prepare in advance and avoid errors during submission.

What the form covers

Form GST RFD-11 is divided into five main sections:

1. Business details: GSTIN, legal name, trade name, principal place of business

2. Financial year: the year for which the LUT is being filed

3. Authorised signatory information: name, designation, and PAN of the person signing

4. Witness details: names, occupations, and addresses of two independent witnesses (neither can be related to the authorised signatory)

5. Declaration: three checkboxes where the exporter confirms compliance with export timelines, GST Act provisions, and IGST payment obligations in case of default

Sample filled LUT – field-by-field guid

On Form GST RFD-11, you are asked to enter the place of filing. This field refers to the principal place of business as registered under your GST registration certificate (REG-06), usually the city where your head office or main branch is located.

For example, if your GST registration shows the principal place of business as Bengaluru, you would enter Bengaluru as the place of filing LUT. It must match exactly with what is stated on your GST registration certificate.

What the place of filing is NOT

• It is NOT the port of shipment (e.g., JNPT or Chennai Port)
• It is NOT the foreign buyer’s location or country
• It is NOT the location of a secondary branch or warehouse

If you have multiple GST registrations across states, file a separate LUT for each GSTIN under the respective state’s principal place of business. A mismatch between the place of filing and your GST registration can trigger validation errors on the portal and rejection of the LUT submission.

Both LUT and Bond allow exporters to ship goods or services without paying IGST upfront, but they apply to different situations. Here’s how they compare:

For 99%+ of GST-registered exporters, LUT is the default and recommended path. Bond with a bank guarantee is a fallback reserved for businesses with a prior tax-evasion prosecution history above ₹2.5 crore.

Service exporters like IT companies, consultants, designers, freelancers, BPOs, and others have specific questions about LUT that goods exporters don’t. Here’s what you need to know.

Is LUT mandatory for export of services?

If you are GST-registered and want to export services without paying IGST: yes, LUT is mandatory. The alternative is to pay 18% IGST on every service invoice and claim it back as a refund, which creates a 6+ month working-capital drag for most businesses.

The turnover threshold caveat

Service exporters with annual turnover below ₹20 lakh (₹10 lakh in special-category states) are not mandatorily required to register for GST under Section 22 of the CGST Act. If unregistered, no GST liability arises and no LUT is needed. However, most service exporters register voluntarily because foreign clients prefer invoicing from a GST-registered entity. In that case, LUT becomes mandatory to claim zero-rated supply.

Common service-exporter scenarios that require LUT

• Software and IT services billed to overseas clients
• Consulting, advisory, and legal services delivered remotely
• Design, creative, and content services for foreign companies
• Freelance work invoiced to foreign businesses or individuals
• Customer support, BPO, and KPO services

What ‘export of services’ means under GST

Under Section 2(6) of the IGST Act, a supply qualifies as an export of services if all five conditions are met: (1) the supplier is in India, (2) the recipient is outside India, (3) the place of supply is outside India, (4) payment is received in convertible foreign exchange, and (5) the supplier and recipient are not merely establishments of the same person.

Payment routing and FEMA compliance

For a service export to be zero-rated under LUT, the payment must be received in convertible foreign exchange and converted to INR within one year (extendable) under FEMA regulations. The eFIRA or FIRC document serves as proof of this foreign exchange realisation — it is the documentary evidence linking the LUT-filed export invoice to the actual foreign payment received.

Common mistakes in LUT filing are leaving form fields incomplete, failing to renew the LUT at the start of the financial year, and missing export timelines. These issues can delay approval, affect compliance, or lead to unwanted IGST payments on exports.

Next, mistakes in LUT filing can lead to delays, penalties, or even the need to pay IGST. Here are pitfalls to watch out for.

Another thing to keep in mind is that failing to meet the specific conditions for LUT approval can lead to revoking of the LUT usage itself. In such a case, exporters have to submit a bond and a bank guarantee instead. This bank guarantee cannot exceed 15% of the bond’s value. Playing safe and resolving potential mistakes in LUT filing can keep you away from such predicaments.

With these mistakes in mind, managing LUT filing becomes more predictable, and far less stressful.

In India’s GST regime, the Letter of Undertaking is a foundational document for anyone in the exporting business. It completely simplifies compliance and improves contemporary cash flow. The LUT represents a modern approach to tax governance.

However, accuracy and timely filing are essential. As international business becomes more dynamic, exporters need integrated systems. If you'd prefer to automate and simplify the entire process, there’s a smarter way: Xflow.

LUT handles the GST side of export compliance. The next step, receiving the foreign payment, generating the FIRA, and reconciling against the LUT-filed invoice, is where Xflow fits in.

Xflow auto-generates eFIRA within 24 hours of each inward remittance, matching it to the LUT-claimed export so your GST documentation and FEMA records stay in sync. This means every LUT-filed invoice gets an automatic paper trail, without any manual chasing.

Visit Xflow’s website today to learn more.