Educational guide
How to Invoice in Singapore
What a Singapore tax invoice must show, when GST registration becomes compulsory and how the GST InvoiceNow Requirement is phased in, each quoted from IRAS with the page's own date.
This page is for general education only. Tax law, e-invoicing rules, and invoice mandates vary by sector, threshold, and updates from authorities. Confirm requirements with a qualified accountant, lawyer, or government guidance for your situation.
IRAS's "Current GST rates" page (Singapore, last updated 13 June 2025) says "The current GST rate in Singapore is 9%." It adds that "GST-registered businesses are required to charge and account for GST at 9% on all sales of goods and services in Singapore unless the sale can be zero-rated or exempted under the GST law." Whether you have to register at all depends on turnover: IRAS's "Do I need to register for GST" page (Singapore, last updated 15 September 2026) says "You must register for GST if your taxable turnover is:" and then sets out a retrospective view and a prospective view. It notes "All currency/ monetary amounts stated in this webpage refer to Singapore dollars."
Once you're registered, IRAS's "Invoicing customers" page (Singapore, last updated 30 October 2026) says a tax invoice must be issued "To your GST-registered customer" and "Within 30 days from the time of supply." Invoicing is also going digital: IRAS's "GST InvoiceNow Requirement" page (Singapore, last updated 8 October 2026) says "All GST-registered businesses must submit invoice data to IRAS using InvoiceNow-Ready Solutions." and "This is mandatory and will be rolled out in phases."
Worked example, with sample figures in Singapore dollars (S$): a GST-registered design studio bills a GST-registered client for a logo package at S$2,400.00 plus 5 hours of revisions at S$70.00 an hour (S$350.00), which comes to S$2,750.00 before GST. At the rate in the IRAS quote above ("9%"), and using what IRAS calls the "Subtotal method", GST is S$2,750.00 × 9% = S$247.50, so the total payable is S$2,997.50. The item-by-item method gives the same GST here (S$216.00 + S$31.50). The total is above the limit IRAS sets for a simplified tax invoice, so the studio issues a full tax invoice.
Invoice checklist for Singapore
Each item has a note on what to include and when it applies.
The words "Tax Invoice"
RequiredIRAS's "Invoicing customers" page (Singapore, last updated 30 October 2026) says the invoice "Must state" this "in a prominent place".
Supplier's name and address
RequiredThe same IRAS list (last updated 30 October 2026) includes "Supplier's name" and "Supplier's address".
Supplier's GST registration number
RequiredIRAS (Singapore, last updated 30 October 2026): "Your GST registration number must be clearly shown on the tax invoices."
Invoice date and number
RequiredIRAS's list (last updated 30 October 2026) has "Date of issue of the invoice" and "Invoice identifying number".
Customer's name and address
RequiredListed by IRAS (last updated 30 October 2026) as "Customer's name" and "Customer's Address".
Description of what you supplied
RequiredIRAS (last updated 30 October 2026): "Description of goods/services supplied".
GST rate and amounts
RequiredIRAS's list (last updated 30 October 2026) includes "GST Rate", "Total amount payable excluding GST", "GST amount" and "Total amount payable including GST".
Singapore dollar amounts on foreign-currency invoices
RequiredIRAS (last updated 30 October 2026): "If you invoice your customer in a foreign currency, these items must be converted into Singapore dollars using the approved exchange rates for GST purpose".
Tax and regulatory themes in Singapore
GST rate
IRAS's "Current GST rates" page (Singapore, last updated 13 June 2025): "The current GST rate in Singapore is 9%." Its history table shows the rate was "8%" from "1 Jan 2023 to 31 Dec 2023".
Compulsory registration
IRAS's "Do I need to register for GST" page (Singapore, last updated 15 September 2026) says "You must register for GST if your taxable turnover is:" "Under the retrospective view, more than $1 million at the end of the calendar year, or" "Under the prospective view, expected to be more than $1 million in the next 12 months". Check IRAS's registration pages for your situation.
When a tax invoice is due
IRAS's "Invoicing customers" page (Singapore, last updated 30 October 2026) says a tax invoice must be issued "Within 30 days from the time of supply." It also lists when one is not needed, for example "To a non-GST registered customer".
Simplified tax invoices
The same IRAS page (last updated 30 October 2026) says "You may issue a simplified tax invoice instead of a regular tax invoice if the total amount payable for your supply (including GST) does not exceed $1,000."
GST InvoiceNow Requirement
IRAS's "GST InvoiceNow Requirement" page (Singapore, last updated 8 October 2026) describes InvoiceNow as "Singapore's nationwide e-invoicing network based on the Peppol standard." Its phase table starts on "1 Nov 2025" with "Companies that register for GST voluntarily within 6 months of incorporation date." and runs to "1 Apr 2031" for "Existing GST-registered businesses with total annual supplies > S$4,000,000".
Keeping invoices
IRAS's "Invoicing customers" page (Singapore, last updated 30 October 2026): "You must keep the tax invoices issued to your customers, and those given to you by your suppliers, for at least 5 years."
Quoting prices
IRAS's "Displaying and quoting prices" page (Singapore, last updated 25 September 2026): "If you are GST-registered, you must display and quote prices inclusive of GST to the public."
Payment methods in Singapore
Availability depends on banks, platforms, and contract terms.
- Bank transfer
- Card payment
Business and cultural tips for Singapore
- Pick one way to calculate GST and stick to it. IRAS (Singapore, last updated 30 October 2026) describes an "Item-by-item method" and a "Subtotal method" and says "Both methods are acceptable and you must apply the chosen method consistently."
- Round the GST total to the cent. IRAS (last updated 30 October 2026): "You can round the total GST to be paid on all goods and services to the nearest cent (i.e. two decimal places)."
- A customer who isn't GST-registered can get a receipt instead. IRAS (last updated 30 October 2026): "If your customer is not GST-registered, you may issue a receipt instead of a tax invoice."
- Find your own InvoiceNow date. IRAS (last updated 8 October 2026) says businesses "can also check their implementation date using the GST InvoiceNow Implementation Date Calculator".
Questions about invoicing in Singapore
Invoicing guides for other countries
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At a glance
| Situation | What IRAS says (Singapore) |
|---|---|
| Customer is GST-registered | A tax invoice must be issued "Within 30 days from the time of supply." (Invoicing customers, last updated 30 October 2026) |
| Small supplies | A simplified tax invoice is allowed if the total "(including GST) does not exceed $1,000." (Invoicing customers, last updated 30 October 2026) |
| Customer isn't GST-registered | "If your customer is not GST-registered, you may issue a receipt instead of a tax invoice." (Invoicing customers, last updated 30 October 2026) |
| Invoicing in another currency | Amounts "must be converted into Singapore dollars using the approved exchange rates for GST purpose" (Invoicing customers, last updated 30 October 2026) |
| E-invoicing | "This is mandatory and will be rolled out in phases." (GST InvoiceNow Requirement, last updated 8 October 2026) |
When this isn't for you
This guide covers everyday invoicing by GST-registered businesses in Singapore. For customer accounting, reverse charge, overseas vendor registration, self-billing or investment precious metals, IRAS has separate pages for each of those cases, or check with a local accountant.