How do I calculate GST on an invoice?

If your prices are before GST, multiply each line by the rate: $500 at 10% is $50 of GST, for a total of $550. If your prices already include GST, the tax is the price times the rate divided by one plus the rate. In Australia that is one eleventh, so $550 includes $50.

What is the difference between CGST, SGST and IGST?

They are the parts of India's GST. CGST (central) and SGST (state), or UTGST in a union territory, are charged together on a sale within one state. IGST (integrated) is charged instead on a sale from one state to another. The place of supply decides which applies.

Do I need an HSN or SAC code on every line?

The CBIC summary of Rule 46 lists the HSN code of goods or the accounting code of services as a particular of a tax invoice, so give each line its code. How many digits you must show depends on rules we have not checked here, so confirm that on the GST portal or with your adviser.

Should I charge GST if I am not registered?

No. Only registered businesses charge GST. Registration is required in Australia from $75,000 of GST turnover, in New Zealand from $60,000, in Singapore above $1 million of taxable turnover, and in Canada once you pass the $30,000 small supplier limit. Below those levels you can usually register by choice.

What HST rate applies in Nova Scotia?

14%. The provincial part of the HST fell from 10% to 9% on April 1, 2025, so the combined rate dropped from 15% to 14%. The Canada mode uses 14% when you choose Nova Scotia. Check older templates, which may still show 15%.

GST Invoice Generator for AU, NZ, India, SG and Canada

GST invoice generator with five country modes

This free GST invoice generator has modes for Australia, New Zealand, India, Singapore and Canada. Each mode sets the rate, the tax number label and the totals the way that country's tax office describes them, including CGST and SGST or IGST for India and GST or HST by province for Canada. Download a PDF when you finish.

How to use the GST invoice maker

Pick the country first, because each mode asks for slightly different details. Then tick that you are registered, choose whether your prices are before GST or include it, and fill in the lines. The tax is worked out per line and totalled at the bottom, and your draft stays saved in this browser.

Australia, New Zealand and Singapore ask for your registration number; the mode fills in the standard rate.
India asks for the place of supply and an HSN or SAC code on each line.
Canada asks for the province or territory, which sets GST or HST and the rate.
Change the rate on any line, or mark it exempt, when it differs from the default.

The five modes at a glance

The modes differ in rate, in the name of the registration number and in one or two rules that catch people out. This table sums up what each one sets, based on official tax office pages checked in October 2026. Prices and thresholds are in local currency.

Mode	Tax and rate	Your number	Rule to know
Australia	GST 10%	ABN, 11 digits	Buyer’s identity or ABN on sales over $1,000
New Zealand	GST 15%	GST number, same as your IRD number	Buyer details on supplies over $1,000
India	CGST plus SGST, or IGST; main slabs 5% and 18%	GSTIN, 15 characters	HSN or SAC per line, place of supply
Singapore	GST 9%	GST registration number, often your UEN	“Tax Invoice” shown prominently
Canada	GST 5%, or HST 13% to 15%	BN plus RT and a 4 digit reference	Show HST as one combined rate

India: CGST plus SGST, or IGST

For a sale within one state, the India mode shows central tax (CGST) and state tax (SGST, or UTGST in a union territory) as separate amounts. For a sale to another state it charges IGST instead. Which one applies depends on the place of supply, so set that before you add lines.

The CBIC summary of Rule 46 lists what else the document needs, including:

your GSTIN, and the buyer’s GSTIN or UIN if they are registered;
a consecutive serial number, unique for the financial year, using letters, numerals, hyphens or slashes;
the HSN code for goods or the accounting code (SAC) for services;
the place of supply with the state name for inter-state supplies;
whether tax is payable on reverse charge;
your signature or digital signature.

For an unregistered buyer with a taxable value of fifty thousand rupees or more, add their name, address and delivery address with the state name and code.

Canada: GST or HST by province

Choose the province or territory where the supply is made and the mode sets the right tax. HST is 15% in New Brunswick, Newfoundland and Labrador, and Prince Edward Island, 14% in Nova Scotia since April 1, 2025, and 13% in Ontario. Everywhere else, GST is 5%.

The CRA asks you to show the rate, and to show HST as one total rate rather than its federal and provincial parts. Your GST/HST number is needed on sales of $100 or more, and from $500 your buyer’s name, a short description and the payment terms are needed too. Provincial taxes such as BC PST and Quebec QST are separate from GST/HST.

Australia, New Zealand and Singapore

These three modes each use a single standard rate, so the main job is getting the wording and the totals right. Each tax office describes a slightly different set of details for the document.

Australia: GST is 10%, one eleventh of a GST inclusive price. The words “tax invoice” must appear, and a business that is not registered must not use them.
New Zealand: since 1 April 2023, Inland Revenue asks for “taxable supply information” rather than a titled document. Over $200 you may show the GST exclusive amount, GST and total, or a GST inclusive total with a statement that GST is included.
Singapore: GST is 9%. Foreign currency invoices must also show the amount before GST, the GST and the total in Singapore dollars. GST may be rounded to the nearest cent.

Example: a New Zealand bill over $1,000

This example shows a signwriter in Hamilton billing a physiotherapy clinic. Because the total is over $1,000 and the buyer is GST registered, the buyer’s name and address are included. The business names, the GST number and the prices are invented for illustration.

Line	Qty	Unit price	Amount
Shopfront vinyl lettering	1	$980.00	$980.00
Window decal set	2	$145.00	$290.00
Installation, hours	3	$75.00	$225.00
Total before GST			$1,495.00
GST at 15%			$224.25
Total including GST			NZD 1,719.25

Seller: Kowhai Signwriting Ltd, GST number 123-456-789. Buyer: Harbourside Physio Ltd, with its street address.