What Are the Types of Invoices in GST? Tax Invoice vs Bill of Supply

What Are the Types of Invoices in GST? Tax Invoice vs Bill of Supply

In day-to-day business conversations, people often use the words "invoice," "bill," "receipt," and "cash memo" interchangeably. Under India's Goods and Services Tax (GST) framework, however, these terms have exact legal definitions governed by Section 31 of the CGST Act, 2017 and Rules 46 through 55A of the CGST Rules.

Using the wrong document format can cause severe headaches. Issue the wrong type of bill to a commercial buyer, and they will be legally blocked from claiming Input Tax Credit (ITC) on their purchase. Issue a tax-collecting invoice when you are registered under the composition scheme, and you violate tax compliance rules.

This guide clarifies the statutory document types recognized under Indian GST law, contrasts the two foundational commercial documents (the Tax Invoice and the Bill of Supply), details their mandatory fields, and explains how to select the right document for every transaction.

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The Primary Distinction: Tax Invoice vs. Bill of Supply

While accountants and enterprise ERP platforms handle various specialized vouchers, the vast majority of everyday commercial transactions in India rely on two primary customer-facing documents:

1. Tax Invoice (Issued under Section 31(1) and Rule 46): The primary commercial document issued by a registered taxpayer making taxable supplies of goods or services. It explicitly charges GST (CGST/SGST or IGST) and enables eligible registered buyers to claim Input Tax Credit.
2. Bill of Supply (Issued under Section 31(3)(c) and Rule 49): A specialized billing document issued when tax cannot or must not be collected on the supply. It is used either because the goods/services are legally exempt from GST or because the seller is enrolled in the Composition Scheme.

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What Is a Tax Invoice? Rules and Mandatory Fields

A Tax Invoice is the backbone of the entire GST value-added tax chain. Because it transfers tax liability to the buyer and simultaneously creates an Input Tax Credit entitlement, its format is strictly regulated.

Under Rule 46 of the CGST Rules, 2017, every valid Tax Invoice must contain the following mandatory details:

1. Name, Address, and GSTIN: Full legal identification of the supplier.
2. Consecutive Serial Number: A unique serial number, not exceeding 16 characters, containing only letters, numbers, or special characters (hyphen '-' or slash '/'), unique for each financial year.
3. Date of Issue: The exact calendar date on which the invoice was generated.
4. Recipient Details (B2B): Name, address, and GSTIN (or UIN) of the registered buyer.
5. Recipient Details (B2C above ₹50,000): If supplying to an unregistered consumer where the taxable value is ₹50,000 or more, the invoice must state the recipient's name, delivery address, state name, and state code.
6. HSN / SAC Code: Harmonized System of Nomenclature code for goods or Services Accounting Code for services (compliant with current turnover-based digit requirements).
7. Description of Goods or Services: Clear trade description of each line item.
8. Quantity and Unit: Units of measurement (e.g., kilograms, pieces, meters).
9. Total Value and Taxable Value: Item-level breakdown of the price, deducting discounts or rebates.
10. Tax Rate and Tax Amounts: Explicit separation of CGST, SGST/UTGST, IGST, and cess.
11. Place of Supply: State name where the supply is deemed to take place, particularly crucial for inter-state deliveries.
12. Signature or Digital Signature: Physical signature or compliant digital authorization by the supplier or an authorized representative.

A Practical Example:
Aditi operates an electronics wholesale store in Bengaluru. She sells 10 barcode scanners worth ₹40,000 (taxable value) to a retail firm in Mysuru. Aditi issues a Tax Invoice showing 18% GST (9% CGST = ₹3,600, 9% SGST = ₹3,600) with a grand total of ₹47,200. Because this is a compliant Tax Invoice featuring the buyer's GSTIN, the retail firm can claim ₹7,200 as Input Tax Credit against their own output taxes.

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What Is a Bill of Supply? When Is It Used?

A Bill of Supply is issued in circumstances where the transaction does not involve collecting tax from the customer:

1. Supplies Made by Composition Dealers: Taxpayers enrolled under the Section 10 Composition Scheme pay a flat turnover tax out of their own revenue. They are legally barred from collecting tax from their customers. Therefore, they must issue a Bill of Supply rather than a Tax Invoice.
2. Supplies of Wholly Exempted Goods or Services: If a regular GST-registered vendor sells products that have a 0% GST rate or are formally notified as exempt (such as fresh fruits, unbranded agricultural grains, fresh milk, or curd), they issue a Bill of Supply for those specific items.
3. Suppliers Operating Under Special Exemption Notifications: Certain notified categories of service providers who do not levy output tax.

Mandatory Fields on a Bill of Supply

Under Rule 49 of the CGST Rules, a Bill of Supply is simpler than a Tax Invoice because it omits tax calculation columns, but it still requires:

Supplier name, address, and GSTIN

Consecutive serial number (maximum 16 characters, unique per financial year)

Date of its issue

Recipient details (if registered, name, address, and GSTIN)

HSN code of goods or SAC for services

Description of goods or services, quantity, and total value

Signature or digital signature of the supplier

Statutory Warning on Composition Bills: Rule 49 mandates that if a composition taxpayer issues a Bill of Supply, the top of the document must prominently feature the words:
"Composition taxable person, not eligible to collect tax on supplies."

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What About Other Invoice Types and Documents?

When people search "what are the three types of invoices in GST", they are usually encountering additional specialized documents defined in the statutory rules for specific commercial workflows:

1. Invoice-cum-Bill of Supply (Rule 46A)

What happens if a registered departmental store sells both taxable items (like shampoo taxed at 18%) and exempt items (like loose organic pulses taxed at 0%) to the same customer in a single cart? Under Rule 46A, instead of printing two separate slips, the merchant can issue a single "Invoice-cum-Bill of Supply". The document itemizes each product, detailing tax for the taxable items and noting nil tax for the exempt items.

2. Receipt Voucher and Refund Voucher (Section 31(3)(d) & (e))

When a business receives an advance payment for goods or services before the actual delivery takes place, it must issue a statutory Receipt Voucher.

If that supply is subsequently cancelled and no invoice was generated, the advance is returned accompanied by a Refund Voucher.

3. Payment Voucher (Section 31(3)(g))

When a registered taxpayer purchases goods or services from an unregistered vendor that fall under the Reverse Charge Mechanism (RCM), the registered recipient pays the tax and must issue a Payment Voucher at the time of making payment to the supplier.

4. Credit Notes and Debit Notes (Section 34)

Credit Note: Issued when the taxable value or tax charged in an original invoice exceeds what is actually payable (e.g., goods returned by the buyer or post-sale discount given).

Debit Note: Issued when the taxable value or tax charged in the original invoice was less than what should have been charged (e.g., price escalation or unexpected additional charges).

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What Is the "Best" Invoice for Your Business?

Search queries often ask "what is the best invoice?" In statutory accounting, there is no single "best" format: the only correct invoice is the one that strictly satisfies the statutory requirements of your tax registration status and the transaction at hand:

If you are a regular GST taxpayer selling taxable items to either B2B or B2C buyers: You must issue a Tax Invoice.

If you are a composition dealer: You must issue a Bill of Supply.

If you sell a mixture of taxable and exempt groceries at a retail checkout: An Invoice-cum-Bill of Supply provides the cleanest customer experience.

Practical Tips for Small Businesses

1. Never Skip Consecutive Numbering: The GST department checks sequential invoice numbering during assessments. Gaps in serial numbers without explanation raise red flags. 2. Verify HSN Codes: Ensure you use the correct HSN code. You can verify product codes using our free HSN Code Finder. 3. Automate Calculations: Manual invoice typing often leads to rounding errors in CGST and SGST splits. Modern billing tools like BillEase automate tax slab splitting, maintain sequential invoice registers, and allow one-click sharing of digital receipts directly to customer WhatsApp accounts.

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Frequently Asked Questions

Can a regular taxpayer issue a Bill of Supply?

Yes, but only when supplying goods or services that are legally exempt from GST. For any taxable supply, a regular taxpayer must issue a Tax Invoice.

Is an invoice valid without the buyer's GSTIN?

For sales to end consumers (B2C transactions), the invoice is valid without a buyer GSTIN. However, for sales to other registered businesses (B2B), the buyer's GSTIN is essential; without it, the buyer cannot reconcile the purchase in GSTR-2B or claim Input Tax Credit.

Can I handwrite a Tax Invoice?

Yes. Hand-written Tax Invoices on printed duplicate books are legally acceptable, provided they contain all mandatory fields specified under Rule 46 (including consecutive serial numbers and GSTIN). However, digital generation reduces calculation errors and simplifies monthly return filing.

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Disclaimer: This document is designed for informational and educational purposes based on Section 31 of the CGST Act and Chapter VI of the CGST Rules. Businesses should review their specific operational model with a qualified tax professional to ensure total document compliance.