Free Invoice Number Generator
Sequential, GST-compliant invoice numbers
Generate sequential invoice numbers with a custom prefix, financial year, and number format. Copy one or all at once — free, no account needed.
What Is an Invoice Number Generator?
An Invoice Number Generator creates sequential, uniquely formatted invoice numbers for your business. Under GST rules in India, invoices must have unique sequential numbers within each financial year. This free tool lets you set a custom prefix (like INV or your company code), choose the financial year format, pick your number padding style, and generate up to 100 invoice numbers at once — ready to copy and use in any billing system or template.
How to Generate Invoice Numbers in 3 Steps
Step 1 — Set Your Prefix & Year
Choose a prefix like INV, BILL, or your company code. Select the year to include (e.g. 2025-26 for Indian financial year). These appear at the start of each invoice number.
Step 2 — Configure the Starting Number & Count
Set the starting sequence number (e.g. 1 if you're starting fresh, or 101 if continuing from existing invoices). Set how many invoice numbers you need to generate.
Step 3 — Copy & Use
Your invoice numbers appear instantly. Copy a single number or copy all numbers at once. Use them in your invoices, billing system, or spreadsheet.
Who Uses This Invoice Number Generator?
Freelancers & Consultants
Generate a full year's worth of invoice numbers at the start of each financial year to stay organised.
Small Business Owners
Create sequential, GST-compliant invoice numbers with a professional prefix and year format.
Accountants & Billing Teams
Pre-generate invoice numbers for the billing team so every invoice follows the right sequence.
E-commerce & Online Sellers
Batch-generate order-specific invoice numbers that match your order management system.
Frequently Asked Questions
What is a good invoice number format?
A common Indian format is: PREFIX/YEAR/SEQUENCE — for example, INV/2025-26/001. This makes invoices easy to sort by year, identify by prefix, and track sequentially.
Is it mandatory to have sequential invoice numbers in India?
Yes. Under GST rules in India, invoice numbers must be sequential, unique, and should not repeat within a financial year. Breaking the sequence can cause issues during GST audits.
Can I use my company name as a prefix?
Yes. Using a short company code (e.g. ABC for ABC Traders) as the prefix makes invoices easily identifiable as yours. Keep it short — 2 to 5 characters is ideal.
What is the difference between financial year and calendar year numbering?
Indian businesses typically reset invoice numbers each financial year (April–March), using formats like 2025-26. Calendar year numbering resets on January 1. Choose based on your accounting cycle.
Can I start from a number other than 1?
Absolutely. Set the 'Starting Number' field to any number. This is useful if you're migrating from another system and need to continue your existing sequence.
Is this tool free?
Yes, completely free. No sign-up, no limits on how many numbers you generate.