GST invoices for Indian service businesses
An Indian GST invoice carries more detail than most: GSTIN, place of supply, SAC codes and the split between central and state tax. Here is what the rules ask for, where WhizInvoice helps, and where you will need something more.
How GST applies to your services
Since 22 September 2025 GST has two main rates, a standard rate of 18% and a merit rate of 5%, plus a special rate of 40% for a select few goods and services. Most business services sit at 18%. Some personal services moved down to 5% in that reform, gyms, salons, barbers and yoga centres among them, so check the rate notified for your exact service.
Which tax you charge depends on where the supply goes. Within your own state you charge central tax and state tax, half each, so 18% becomes 9% CGST plus 9% SGST (or UTGST in a union territory). For a customer in another state you charge integrated tax, IGST, at the full rate.
You must register once your aggregate turnover in a financial year exceeds ₹20 lakh, or ₹10 lakh in some special category states. If you are registered under the composition scheme, or make only exempt supplies, you issue a bill of supply instead of a tax invoice and charge no GST.
Indian GST invoicing at a glance
- GST rates
- 18% standard, 5% merit rate, 40% for a select few items. The current rates for services took effect on 22 September 2025.
- Supply within your state
- CGST plus SGST (or UTGST), each at half the rate, for example 9% plus 9%.
- Supply to another state
- IGST at the full rate, for example 18%.
- Registration threshold
- Aggregate turnover over ₹20 lakh in a financial year, ₹10 lakh in some special category states. Goods-only suppliers can have a limit of up to ₹40 lakh where their state has opted for it.
- Tax invoice must show
- Your name, address and GSTIN; a serial number of up to 16 characters, unique for the financial year; the date; the customer’s name, address and GSTIN if registered; the HSN or SAC code; a description; the taxable value after any discount; the rate and amount of CGST, SGST, IGST, UTGST or cess; the place of supply for inter-state supplies; whether reverse charge applies; and a signature, which an electronic invoice does not need.
- Unregistered customers
- From ₹50,000, also their name, address and delivery address with the state name and code.
- HSN or SAC digits
- 4 digits if your aggregate turnover last year was up to ₹5 crore (optional on supplies to unregistered customers), 6 digits above ₹5 crore.
- When to issue
- Within 30 days of supplying a service.
- Tax number label
- GSTIN
- Currency
- Indian rupee, INR (₹)
- Date format
- DD/MM/YYYY
- Paper size
- A4
- E-invoicing
- Required once your aggregate turnover has exceeded ₹5 crore in any financial year since 2017-18. Each invoice in scope needs an Invoice Reference Number and QR code from the government portal, and one issued any other way is not treated as an invoice.
Sources: CBIC (CGST Act sections 22 and 31, CGST Rules 46, 47 and 48, Notification 78/2020-Central Tax) and the GST Council (Notification 10/2023-Central Tax and the 56th and 57th Council meetings), checked October 2026.
What WhizInvoice does for a GST invoice in India
Choose India in Settings and the basics are set. A few Indian rules need a manual step, and they are listed honestly below.
The India preset
Rupees, GST at 18%, the GSTIN label, the Tax invoice title, DD/MM/YYYY dates and A4 paper, filled in at once.
IGST for other states
For a customer in another state, name the tax IGST and the invoice shows a single tax line at the full rate, which is how an inter-state supply is taxed.
Your GSTIN and theirs
Your GSTIN prints under your business name, and a registered customer’s GSTIN prints on their invoices once you save it on their record.
SAC codes in the description
Type the SAC code at the start of each line description so it appears on the invoice beside the service.
Short serial numbers
Invoice numbers run in sequence with a prefix you choose, so you can keep them inside the 16 character limit.
UPI and bank details
Add your UPI ID, account number and IFSC as payment instructions, or a payment link, so customers can pay the day the invoice arrives.
An inter-state invoice with IGST
A web studio in Karnataka billing a client in Maharashtra. The supply crosses state lines, so IGST at 18% applies as a single line and the place of supply is recorded.
Example only, with a fictional business and customer. Your invoices use your own details, tax settings and design.
| Description | Qty | Rate | Amount |
|---|---|---|---|
| Website maintenance, October | 1 | ₹18,000.00 | ₹18,000.00 |
| Landing page design and build | 1 | ₹24,000.00 | ₹24,000.00 |
| Hosting set up and SSL certificate | 1 | ₹6,500.00 | ₹6,500.00 |
Good to know
Should I charge CGST and SGST or IGST?
Charge CGST and SGST, half the rate each, when the place of supply is in your own state. Charge IGST at the full rate when the customer’s place of supply is in another state.
Do I need SAC codes on service invoices?
Yes, with 4 digits if your aggregate turnover last year was up to ₹5 crore and 6 digits above that. Smaller businesses may leave the code off invoices to unregistered customers.
I am on the composition scheme. Which document do I issue?
A bill of supply, not a tax invoice. Composition taxpayers and businesses making only exempt supplies cannot charge GST on their documents.
How soon must I issue a tax invoice for a service?
Within 30 days of supplying the service. Banks, insurers and other financial institutions have 45 days.
Does a PDF tax invoice need a signature?
No. Rule 46 waives the signature for an invoice issued electronically under the Information Technology Act, 2000.
Can WhizInvoice generate e-invoices with an IRN?
No. If e-invoicing applies to you, those invoices must be registered on the Invoice Registration Portal, directly or through software that connects to it. WhizInvoice can still hold your enquiries, quotes and customers.
Get your enquiries and quotes in order
Start on the Free plan with unlimited invoices and one connected website, and no card needed.
Free plan forever. No card needed to start.