Under the GST regime, simply writing "Invoice" on a piece of paper is not enough. The CBIC has strictly defined what information must be present on a document for it to be legally recognized as a Tax Invoice.
The Mandatory Fields List
According to the CGST Rules, every tax invoice issued by a registered person must contain the following particulars:
1. Supplier Details
Name, address, and GSTIN (Goods and Services Tax Identification Number) of the supplier.
2. Invoice Number & Date
A consecutive serial number, containing alphabets, numerals, or special characters (hyphen or dash and slash), unique for a financial year. Maximum 16 characters.
Date of issue of the invoice.
3. Recipient (Buyer) Details
If registered: Name, address, and GSTIN or UIN.
If unregistered and value > ₹50,000: Name and address of the recipient, and address of delivery, along with the name of the State and its code.
4. Item Details & HSN/SAC
Description of goods or services.
HSN (Harmonized System of Nomenclature) code for goods or SAC (Services Accounting Code) for services.
Quantity (for goods) and Unit (e.g., kg, pieces).
5. Value & Tax Details
Total value of supply.
Taxable value after discount.
Rate of tax (CGST, SGST, IGST, UTGST or cess).
Amount of tax charged, shown separately.
6. Place of Supply
State name and State code, especially in the case of inter-state trade or commerce.
7. Signatures
Signature or digital signature of the supplier or their authorized representative. (Exceptions exist for specific electronic invoices).
Why are these fields so critical?
If any of these mandatory fields are missing, the buyer is technically holding a defective invoice. Because the GST portal matches supplier output tax with the buyer's ITC claim, a non-compliant invoice means the buyer's ITC will be rejected, costing them money and damaging your business relationship.
Using a dedicated Business Invoice Generator ensures that you never miss a mandatory field, as the tool prompts you for all required information before allowing the PDF download.