GST Invoice Generator: Complete Guide for Indian Businesses

Need to create GST-compliant invoices for your Indian business? A GST invoice generator helps you create professional, tax-compliant invoices with GSTIN, HSN/SAC codes, and automatic GST calculations.

What is a GST Invoice?

A GST invoice is a tax invoice that complies with India's Goods and Services Tax (GST) regulations. It must include specific information required by the GST law.

Mandatory Fields for GST Invoices:

GSTIN (Goods and Services Tax Identification Number)
- Your 15-digit GST registration number
- Format: 22AAAAA0000A1Z5
Invoice Number
- Must be sequential and unique
- Cannot repeat within a financial year
Invoice Date
- Date of supply or date of issue
Supplier Details
- Name, address, and GSTIN
- State and state code
Recipient Details
- Name, address, and GSTIN (if registered)
- State and state code
HSN/SAC Codes
- HSN (Harmonized System of Nomenclature) for goods
- SAC (Services Accounting Code) for services
GST Breakdown
- CGST (Central GST)
- SGST (State GST) or IGST (Integrated GST)
- Rate and amount for each
Total Amount
- Taxable value
- Total GST
- Invoice total

Why Use a GST Invoice Generator?

1. Ensures Compliance

Automatically includes all mandatory fields required by GST law, reducing risk of penalties.

2. Accurate Tax Calculations

Automatically calculates:

CGST and SGST (for intra-state supplies)
IGST (for inter-state supplies)
Cess (if applicable)

3. Saves Time

Create GST-compliant invoices in minutes instead of hours.

4. Reduces Errors

Eliminates manual calculation mistakes that could lead to GST filing issues.

5. Professional Appearance

Creates invoices that meet legal requirements while looking professional.

How to Create a GST Invoice

Step 1: Enter Your GSTIN

Your 15-digit GST registration number. Example: 29ABCDE1234F1Z5

Step 2: Add Business Details

Legal business name (as registered with GST)
Complete address
State and state code
Email and phone number

Step 3: Add Customer Details

Customer name and address
Customer GSTIN (if they're registered)
State and state code
Place of supply

Step 4: Add Invoice Information

Invoice number (sequential)
Invoice date
Due date

Step 5: Add Products/Services

For each item, include:

Description: Clear description of goods/services
HSN/SAC Code: 4-digit or 6-digit code
Quantity: Number of units
Rate: Price per unit
Taxable Value: Quantity × Rate
GST Rate: 0%, 5%, 12%, 18%, or 28%

Step 6: Review Tax Calculation

The generator automatically calculates:

For Intra-State Supplies (same state):

CGST = Taxable Value × (GST Rate / 2)
SGST = Taxable Value × (GST Rate / 2)

For Inter-State Supplies (different states):

IGST = Taxable Value × GST Rate

Step 7: Generate and Download

Download your GST-compliant invoice as a PDF.

Understanding GST Rates

Common GST Rates in India:

0% GST:

Fresh fruits and vegetables
Milk and milk products
Bread and flour

5% GST:

Household necessities
Edible oils
Sugar, tea, coffee
Coal and medicines

12% GST:

Computers and processed food
Butter, cheese, ghee
Mobile phones

18% GST:

Most goods and services
IT services
Soaps and hair oil
Capital goods

28% GST:

Luxury items
Automobiles
Tobacco products
Aerated drinks

HSN and SAC Codes

What are HSN Codes?

HSN (Harmonized System of Nomenclature) codes classify goods for GST purposes.

Examples:

0201: Meat of bovine animals, fresh or chilled
6403: Footwear with outer soles of rubber/plastics
8517: Telephone sets, smartphones

What are SAC Codes?

SAC (Services Accounting Code) classify services for GST purposes.

Examples:

9983: Information technology services
9982: Management consulting services
9961: Legal services

Do You Need to Include Them?

Mandatory:

Businesses with turnover > ₹5 crore: Must use 6-digit codes
Businesses with turnover ₹1.5 - 5 crore: Must use 4-digit codes

Optional:

Businesses with turnover < ₹1.5 crore: Not required but recommended

GST Invoice Format Requirements

Invoice Number Format:

Must be unique and sequential. Common formats:

INV/2024-25/001
2425/001
GST/AP/2024-25/0001

Never:

Repeat numbers
Skip numbers
Use different series randomly

Date Format:

Use DD/MM/YYYY or DD-MMM-YYYY

✅ 15/01/2025 or 15-Jan-2025
❌ 01/15/2025 (US format - avoid)

Amount Display:

Show values to 2 decimal places:

✅ ₹1,250.00
❌ ₹1250 or ₹1,250.5

Common GST Invoice Mistakes

❌ Mistake #1: Wrong GSTIN

Problem: Using old or incorrect GSTIN Solution: Verify GSTIN on GST portal before invoicing

❌ Mistake #2: Missing HSN/SAC Codes

Problem: Forgetting to include codes when required Solution: Maintain a list of codes for your products/services

❌ Mistake #3: Incorrect Tax Calculation

Problem: Manual calculation errors Solution: Use a GST invoice generator for automatic calculations

❌ Mistake #4: Wrong CGST/SGST vs IGST

Problem: Using CGST/SGST for inter-state supplies Solution:

Same state buyer/seller → CGST + SGST
Different states → IGST only

❌ Mistake #5: Incomplete Customer Details

Problem: Missing customer GSTIN or address Solution: Collect complete information before invoicing

❌ Mistake #6: Non-Sequential Invoice Numbers

Problem: Random or duplicate invoice numbers Solution: Maintain proper sequence; track last invoice number used

GST Invoice for Different Business Types

For Service Providers

Example: IT Consultant

Description: Software Development Services
SAC Code: 998314
Taxable Value: ₹50,000
CGST @ 9%: ₹4,500
SGST @ 9%: ₹4,500
Total: ₹59,000

For Retailers

Example: Electronics Shop

Description: Smartphone
HSN Code: 8517
Taxable Value: ₹20,000
CGST @ 9%: ₹1,800
SGST @ 9%: ₹1,800
Total: ₹23,600

For Manufacturers

Example: Furniture Manufacturer

Description: Office Desk
HSN Code: 9403
Quantity: 5
Rate per unit: ₹8,000
Taxable Value: ₹40,000
CGST @ 9%: ₹3,600
SGST @ 9%: ₹3,600
Total: ₹47,200

For E-Commerce Sellers

Must include additional details:

Marketplace GSTIN
TCS (Tax Collected at Source) if applicable
Shipping charges (with applicable GST)

Reverse Charge Mechanism (RCM)

What is RCM?

Under RCM, the buyer pays GST instead of the supplier.

When RCM Applies:

Services from unregistered persons
- Legal services
- Security services
- Goods transport services
Import of services
Specific notified supplies

RCM Invoice Requirements:

Include note: "Tax payable on reverse charge basis"

E-Invoicing Requirements

Who Needs E-Invoicing?

Currently mandatory for businesses with annual turnover exceeding ₹5 crore (subject to change).

What is E-Invoicing?

Generate Invoice Reference Number (IRN) from IRP portal
QR code on invoice
Real-time reporting to GST system

E-Invoice Components:

IRN (Invoice Reference Number)
- 64-character unique identifier
QR Code
- Contains invoice details
- Scannable for verification
Acknowledgment Number
- From IRP portal

Input Tax Credit (ITC)

Why Proper GST Invoices Matter:

Your customers can claim Input Tax Credit only if your invoice is GST-compliant.

ITC Requirements:

Valid GSTIN of supplier
Proper tax invoice
Goods/services received
Tax paid to government
Returns filed

If your invoice is non-compliant, your customer cannot claim ITC!

GST Filing and Invoice Records

Record Retention:

Must maintain invoice records for 72 months (6 years) from filing annual return.

What to Keep:

Original invoice copies
Payment proof
Delivery challans
E-way bills
Transport documents

Digital vs Paper:

Both formats acceptable, but digital recommended for:

Easy retrieval
Space saving
Backup capability
Quick GST filing

Composition Scheme Invoices

What is Composition Scheme?

Simplified scheme for small businesses (turnover < ₹1.5 crore).

Composition Invoice Requirements:

Must include statement:

"Composition taxable person, not eligible to collect tax on supplies"

Differences:

Cannot charge GST separately
Cannot issue tax invoices
Issue "Bill of Supply" instead
Cannot claim Input Tax Credit

Free GST Invoice Generator Benefits

1. Cost Savings

No need for expensive accounting software just for invoicing.

2. Instant Compliance

Pre-configured with GST requirements.

3. Automatic Calculations

Zero math errors in GST calculations.

4. Professional Format

GST-approved invoice format.

5. Easy to Use

No accounting knowledge required.

Tips for GST Invoicing

1. Maintain Invoice Series

Use consistent, sequential numbering:

Financial Year 2024-25: FY25/001, FY25/002...
Separate series for different types if needed

2. Keep HSN/SAC List Handy

Create a reference list of codes you use frequently.

3. Verify Customer GSTIN

Check validity on GST portal before invoicing.

4. Invoice Immediately

Generate invoices promptly after supply to avoid compliance issues.

5. Backup Regularly

Save digital copies to cloud storage:

Google Drive
Dropbox
OneDrive

6. Review Before Sending

Check:

GSTIN correctness
HSN/SAC codes
Tax calculations
Invoice number sequence
Customer details

Penalties for Non-Compliance

Common Violations and Penalties:

Issuing invoice without GSTIN: ₹10,000

Not issuing invoice: Higher of ₹10,000 or 100% of tax amount

Wrong information in invoice: ₹25,000

Using wrong invoice series: ₹25,000

Not maintaining invoice records: ₹25,000

Prevention: Use compliant GST invoice generator and follow proper procedures.

Frequently Asked Questions

Do I need GST registration to issue invoices?

If your turnover exceeds ₹40 lakh (₹20 lakh for services), GST registration is mandatory. Once registered, you must issue GST invoices.

Can I issue handwritten GST invoices?

Yes, as long as they contain all mandatory fields. However, printed or digital invoices are recommended for professionalism and accuracy.

What if my customer doesn't have GSTIN?

You still need to issue a GST invoice (tax invoice) but can mention "Unregistered" in the GSTIN field.

How do I find HSN/SAC codes?

Search on the GST portal or use HSN/SAC code finders available online. Your GST invoice generator should help with common codes.

Can I issue invoices in languages other than English?

Yes, but English or Hindi is recommended for wider acceptance. Some states may accept regional languages.

What's the time limit for issuing invoices?

For goods: At or before delivery For services: Within 30 days of service completion

Conclusion

A GST invoice generator is essential for Indian businesses to:

✅ Ensure GST compliance
✅ Avoid penalties
✅ Enable customer ITC claims
✅ Maintain professional standards
✅ Simplify tax filing

Don't risk non-compliance with manual invoicing. Use a free GST invoice generator to create perfect GST invoices every time.

Create GST-Compliant Invoices Now

Generate GST Invoice Free → - Includes GSTIN, HSN codes, automatic GST calculation
Download GST Invoice Template → - Pre-formatted for Indian businesses
Learn About Invoice Compliance → - Stay updated with GST rules

Last updated: December 2024 Disclaimer: This guide is for informational purposes. Consult a tax professional for specific advice.

GST Invoice Generator: Complete Guide for Indian Businesses (2025)