Comprehensive Guide to Indian GST Tax Invoices
Under the Goods and Services Tax (GST) regime launched in July 2017, the tax invoice is the single most critical compliance instrument for businesses in India. It serves not only as a bill of sale but as the mandatory statutory voucher required by tax authorities to substantiate Input Tax Credit (ITC) claims by corporate purchasers.
An invalid or improperly formatted GST invoice can lead to ITC disallowance for your clients, late payment disputes, tax department inquiries, and statutory penalties under Section 122 of the Central Goods and Services Tax (CGST) Act.
Mandatory Particulars Under Rule 46 of CGST Rules
Rule 46 stipulates the sixteen mandatory elements that every registered GST supplier must include in their tax invoice:
- Supplier Identity: Registered legal name, address, and 15-character GSTIN.
- Consecutive Serial Number: Unique alphanumeric serial number for the financial year (max 16 characters).
- Date of Issuance: Date the invoice is delivered or issued.
- Recipient Details: Customer name, billing address, and GSTIN (for registered B2B entities).
- Place of Supply: Name of State and 2-digit numeric State Code (e.g., 27 for Maharashtra, 07 for Delhi, 29 for Karnataka).
- HSN or SAC Code: 4 or 6-digit classification code according to turnover tier.
- Description of Goods or Services: Precise item details, quantities, and standard units (PCS, NOS, KGS, SET, HRS).
- Total Taxable Value: Calculated after applying trade discounts.
- Rate of Tax: Explicit percentage of CGST, SGST, or IGST.
- Amount of Tax Charged: Segregated into Central Tax, State Tax, or Integrated Tax.
- Signature: Authorized signature or digital signature stamp.
Determining the Correct GST Type: Intra-State vs Inter-State
The type of GST you must levy depends on the relationship between the Location of the Supplier and the Place of Supply (POS):
Intra-State Supply (CGST + SGST)
When supplier state and customer place of supply are in the same state. The tax is split equally:
Example: 18% slab = 9% CGST + 9% SGST
Inter-State Supply (IGST)
When supplier state and customer place of supply are in different states. The entire tax is levied as Integrated GST:
Example: 18% slab = 18% IGST
Indian State Codes for GST Invoicing
The first two digits of any Indian GSTIN represent the numerical state code. Here are common state codes you must include in your tax invoice:
Our tool automatically detects and populates the two-digit state code whenever you select a state from the dropdown.
Input Tax Credit (ITC) Pass-Through
To ensure your B2B customers can claim Input Tax Credit on the purchases they make from you, always:
- Ensure the customer's 15-digit GSTIN is correctly spelled on the tax invoice.
- Report the invoice in Table 4A of your monthly GSTR-1 return on the GST Portal.
- Ensure the invoice reflects in the buyer's auto-populated GSTR-2B statement before they file GSTR-3B.