Understanding IGST on Proforma Invoices: GST Rules, Format & Compliance Guide

What is a Proforma Invoice?

A **proforma invoice** is a preliminary document issued by a supplier to a prospective buyer, outlining the estimated costs, quantities, and terms for goods or services yet to be delivered. It serves as a quote to help buyers decide on placing an order, similar to a commercial invoice but not representing an actual sale.[1][2]

Key Elements of a Proforma Invoice under GST

Essential components include a unique invoice number, issue date, supplier and buyer addresses (with GSTIN if applicable), description of goods/services with HSN/SAC codes, unit prices, totals, validity period, proposed sale and payment terms, bank details, and supplier signature. Unlike pre-GST, GST proforma invoices must mention GST registration, HSN/SAC codes, and classify taxes as CGST/SGST for intra-state or **IGST** for inter-state supplies.[2][3][5]

Is GST Applicable on Proforma Invoices?

No, GST including **IGST** is not payable on proforma invoices as they are not tax invoices and do not signify a completed supply. GST liability arises only on the final tax invoice post-supply or on advance payments received against it. Proforma invoices fall outside GST scope per Section 31 of CGST Act, 2017.[1][4][5][6]

Understanding IGST Specifically on Proforma Invoices

**IGST** (Integrated Goods and Services Tax) applies to inter-state supplies. While proforma invoices themselves attract no IGST, they must indicate potential IGST classification for transparency, especially in international or cross-state transactions. For exports/imports, include customs certifications. If advance payment is received basis proforma, IGST must be charged and remitted.[2][3]

Proforma Invoice vs. Tax Invoice: Key Differences

• Proforma: Preliminary estimate, no GST payable, issued pre-sale.[1][4]
• Tax Invoice: Issued post-supply, GST (including IGST) applicable, mandatory for claiming ITC.[9]

Steps to Create a Proforma Invoice under GST

1. Assign unique number and date.
2. Add supplier/buyer details with GSTIN.
3. List items with HSN/SAC, quantities, rates, indicating CGST/SGST/IGST.
4. Specify terms, validity, totals (pre/post-tax).
5. Include signature and notes on no GST payment yet.[4]

Including Rent Invoice Considerations

For services like **rent invoice**, proforma can estimate rental charges with SAC code 9972, specifying if intra-state (CGST+SGST) or inter-state (**IGST** at 18%). Ensure clarity on lease terms to avoid disputes, treating it as a service supply under GST.[2][3]

Best Practices and Common Mistakes

Always disclose if prices include/exclude GST, add shipping/other charges, maintain records with GSTIN. Avoid treating proforma as final invoice. For revisions, issue new numbered proforma. Crucial for exports: comply with customs.[3][4]

Legal Compliance and Advance Payments

On advance against proforma, charge GST (IGST for inter-state) via separate receipt voucher. Convert to tax invoice on supply completion. Businesses must keep detailed records for audits.[3]

This guide ensures compliance with GST on proforma invoices, focusing on **IGST** nuances for seamless transactions. Consult tax experts for specifics.