What is an invoice?
An invoice is a document you send to a client requesting payment for goods or services you’ve provided. It records what was sold, how much is owed, and when payment is due. A clear invoice gets you paid faster and makes your business look credible.
An invoice is a request for payment. A receipt is proof a payment was made. You usually send the invoice first, then issue a receipt once the client pays.
What every invoice must include
Your business details
Name, address, email, phone — and your GSTIN if you're GST-registered.
Client details
The client's name, billing address, and GSTIN (for B2B GST invoices).
Invoice number & date
A unique, sequential invoice number plus the issue date and payment due date.
Line items & totals
A line for each item: description, quantity, rate, amount — then sub-total, tax, and grand total.
Step-by-step: build your invoice
Add your business details
Enter your business name, address, contact info, and logo. This is the 'From' block at the top.
Add the client
Enter who you're billing — the 'Bill To' block. Include their GSTIN for B2B transactions.
List your line items
Add a row per item with a clear description, quantity, and unit rate. The amount calculates automatically.
Apply tax and discounts
Choose CGST+SGST (same state) or IGST (other state), set the rate, and add any discount.
Download the PDF
Review the live preview, then download a clean, print-ready PDF to email your client.
Use the free Invoice Generator to do all of this in your browser — nothing is uploaded, and the PDF is generated locally on your device.
A worked example
Say you’re a freelance designer in Maharashtra billing a client in the same state:
| Item | Qty | Rate | Amount |
|---|---|---|---|
| Logo design | 1 | ₹35,000 | ₹35,000 |
| Website UI (12 screens) | 12 | ₹3,500 | ₹42,000 |
| Sub-total | ₹77,000 | ||
| Discount | − ₹5,000 | ||
| Taxable value | ₹72,000 | ||
| CGST (9%) | ₹6,480 | ||
| SGST (9%) | ₹6,480 | ||
| Total | ₹84,960 |
Because the client is in the same state, GST splits into CGST + SGST. If they were in another state, you’d charge a single IGST of 18% (₹12,960) instead.
Common invoicing mistakes to avoid
Skipping the invoice number. Every invoice needs a unique, sequential number for your records and for GST compliance. See invoice numbering best practices.
Forgetting payment terms. State a due date and accepted payment methods. “Due within 15 days” sets a clear expectation.
Wrong GST split. Same-state sales use CGST + SGST; inter-state sales use IGST. Mixing these up is the most common GST invoice error — read the GST invoice format guide.
No amount in words. For higher-value invoices, spelling out the total (“Rupees Eighty Four Thousand…”) reduces disputes and is expected on formal GST invoices.
Related tools
- Invoice Generator — create and download a GST-ready PDF invoice for free
- GST Calculator — check the CGST/SGST/IGST split on any amount
- Discount Calculator — work out discounts before adding them to a bill