Free GST Invoice Format: Create a Professional Invoice in 2 Minutes

You finished the project. The client is happy. Now comes the part many freelancers and small business owners in India quietly dread: sending a proper invoice. You open a blank document, type the client's name, stare at it for a while, and wonder — where do I put the GST? What is an HSN code? Does the invoice number matter?

A good invoice is not paperwork. It is what turns finished work into money in your account. A clear, professional invoice gets paid faster, and a sloppy one gets questioned, delayed, or quietly pushed to the bottom of the client's to-do list.

The good news: you do not need accounting software or a paid subscription. You need to know which fields a GST invoice must have, and a free tool that does the formatting for you.

Try it free → Void Invoice Generator

What a GST invoice must include

If you are GST-registered, every invoice you issue must carry certain details. Missing them can create problems during filing or if a client claims input tax credit. Here is the checklist:

• Invoice number and date. Numbers must be unique and in a continuous series for each financial year, for example INV-2026-001, INV-2026-002.
• Your business details. Name, address, and GSTIN.
• Your client's details. Name, address, and GSTIN if the client is GST-registered.
• Description of goods or services. Write what you actually did — "Logo design, 2 concepts" beats "Design services".
• HSN or SAC code. HSN codes classify goods, SAC codes classify services. Pick the code that matches what you sold.
• Quantity and rate. Even for services, one line with the agreed amount keeps things clean.
• Taxable value and tax breakup. If you and your client are in the same state, show CGST and SGST. If you are in different states, show IGST.
• Total amount. The final figure, in numbers and words.
• Place of supply. The state where the service was delivered or goods were sent.
• Your signature. A digital signature or your name with designation is fine.

If you are not GST-registered — for example, your turnover is below the registration threshold — do not add GST to your bill. Issue a simple bill or bill of supply instead. Only GST-registered businesses can charge GST.

Create your invoice in 2 minutes: step by step

Here is the exact process using a free invoice generator in your browser. No signup, no app to install.

Step 1: Open the invoice generator

Open the Void Invoice Generator on your phone or laptop. Everything runs in the browser, so there is nothing to download.

Step 2: Fill in your business details once

Type your name or business name, address, phone, email, and GSTIN. Save these details in the tool so you never type them again — every future invoice takes seconds, not minutes.

Step 3: Add your client

Enter the client's name, address, and GSTIN if they have one. Double-check the spelling: this name appears on their books too. If you work with repeat clients, keeping their details saved is worth the one-time effort — our guide on organizing 500+ business contacts without Excel chaos shows a simple system for exactly this.

Step 4: Add line items with the right tax split

Add one line per item or service: description, HSN or SAC code, quantity, and rate. Then choose the tax: CGST plus SGST if your client is in your state, IGST if they are in another state. The tool calculates the totals for you, so there is no mental math and no spreadsheet formulas to break.

Step 5: Set the invoice number and payment terms

Use the next number in your series — never reuse or skip numbers casually. Add a clear due date, such as "Payment due within 7 days", and your preferred payment method (UPI ID, bank details). Invoices with a visible due date get paid noticeably faster than ones without.

Step 6: Download the PDF and send it

Download the invoice as a PDF and send it by email or WhatsApp. A PDF looks professional and cannot be silently edited; avoid sending screenshots or editable files.

5 mistakes that delay your payment

• Reused or random invoice numbers. "Invoice #1" for every client, or numbers that jump around, look unprofessional and create filing confusion. Keep one continuous series per financial year.
• Missing or wrong GSTIN. If your client is GST-registered and your invoice lacks their GSTIN, they cannot claim input tax credit — and they will ask you to reissue the invoice.
• Wrong tax split. Charging CGST and SGST to a client in another state (or IGST to one in your own state) is a common beginner error. Same state: CGST + SGST. Different state: IGST.
• No payment terms on the invoice. "Pay whenever" means "pay never, maybe". Always print a due date and your payment details.
• Chasing payments by memory. Unpaid invoices are usually follow-up failures, not client dishonesty. A gentle reminder on day 3 and day 7 after the due date works wonders. If follow-ups keep slipping, read how a free CRM helps freelancers never lose a client follow-up and build a simple reminder habit.

Frequently asked questions

Do I need GST registration to send an invoice?

No. Anyone can send an invoice or bill for their work. GST registration is required only once your turnover crosses the prescribed threshold (or earlier in special cases, such as inter-state supply of goods). If you are not registered, simply do not charge GST — issue a plain bill instead.

What invoice number format should I use?

Keep it simple and consistent: a prefix, the financial year, and a running number, like INV-26-27-001. The only hard rules are that numbers must be unique and in continuous sequence within each financial year. Never reuse a number.

CGST + SGST or IGST — which one do I charge?

It depends on where your client is. Same state as you: split the tax into CGST and SGST (each half the total rate). Different state: charge IGST at the full rate. Getting this wrong is the most common mistake on first invoices, so double-check the client's state before you send.

Can I edit an invoice after sending it?

Do not edit and resend the same invoice. Standard practice is to issue a credit note (to reduce the amount) or a debit note (to increase it) referencing the original invoice number. This keeps your books clean and your filing consistent.

Send the invoice today, not next week

The best invoice format is the one you actually use. Save your business details once, keep your client list tidy, number your invoices in one clean series, and send every invoice as a PDF the day the work is done — not "when you get time". If invoicing is just one of many small tasks eating your week, our list of 25 free online tools every freelancer should bookmark covers the rest of the kit, from contracts to SEO.

Try it free → Void Invoice Generator