GST Invoice Format Explained with Example

Complete GST Invoice Format

Header Section

Business Name: [Your Registered Business Name] GSTIN: [15-digit GST number] Address: [Registered Address] Phone: [Contact Number] Email: [Business Email]

Invoice Details

Invoice Number: [Unique sequential number] Invoice Date: [DD/MM/YYYY] PAN: [10-digit PAN]

Customer Details

Customer Name: [Full Name] GSTIN: [15-digit, if registered] Address: [Complete Address]

Itemized Section

| Description | HSN/SAC | Qty | Rate | Amount |

Tax Calculation

Subtotal: ₹X CGST: [9% or applicable rate] SGST: [9% or applicable rate] OR IGST: [18% or applicable rate]

Total: ₹X

Understanding CGST and SGST

• CGST (Central GST) — Collected by central government
• SGST (State GST) — Collected by state government
• Both apply to intra-state sales
• IGST (Integrated GST) applies to inter-state sales

HSN Code Explained

HSN (Harmonized System of Nomenclature) is a 4-digit code classifying products globally. For example:

• 8471 — Automatic data processing machines
• 6204 — Women's clothing
• 2710 — Petroleum products

SAC Code for Services

SAC (Services Accounting Code) is a 6-digit code for services. Examples:

• 998135 — Consulting services
• 998141 — Account audits
• 998115 — Software development

Complete Invoice Example

SHARMA ELECTRONICS
GSTIN: 27AABCU9603R2Z1
Address: 123 Business Park, Mumbai

Invoice #2026-001 | Date: 15/05/2026

Bill To: ABC Industries, GSTIN: 09AABCT1234567K1

| Monitor 24" LG | 8517 | 2 | ₹12,000 | ₹24,000 |
| Mouse Wireless | 8471 | 5 | ₹800 | ₹4,000 |

Subtotal: ₹28,000
CGST (9%): ₹2,520
SGST (9%): ₹2,520
Total: ₹33,040

Invoice Numbering Rules

• Numbers must be sequential
• Cannot skip numbers
• Start from 001 for each financial year
• Once issued, cannot be deleted (must use credit note)
• If you manually create invoices, number them by hand

Frequently Asked Questions

Q: Is PAN mandatory on GST invoices? A: Yes, your 10-digit PAN must appear on all invoices.

Q: Can I use alphabets in invoice numbers? A: Yes, but they must maintain sequence (INV-001, INV-002, etc.).

Q: What if I skip an invoice number by mistake? A: Issue a debit note for the missing number explaining the error.

Q: How detailed should item descriptions be? A: Specific enough that the customer knows exactly what they purchased.

Q: Do I need to mention PAN on every line item? A: No, only once at the top of the invoice.