For companies choosing where to establish a presence or expand, tax is one area where the two markets diverge sharply. Singapore has Goods and Services Tax (GST), administered by the Inland Revenue Authority of Singapore (IRAS); Vietnam has Value-Added Tax (VAT), administered by the General Department of Taxation. Both are consumption taxes on the value added to goods and services, so they look similar, but the practical rules around rates, registration, invoicing, filing, input tax recovery and cross-border transactions are not interchangeable.
So, what is the actual difference between Singapore GST and Vietnam VAT, and what should businesses operating across both markets be aware of? We looked at the wider relationship between the two economies in our post on why Singapore is investing so much in Vietnam. The employment-cost side is a useful parallel: Singapore’s Central Provident Fund (CPF) and Vietnam’s social, health and unemployment insurance (SHUI) land on payroll in quite different ways, as our post comparing CPF and SHUI sets out.
TL;DR – Singapore GST and Vietnam VAT follow the same broad principle, but the rules businesses work with are not interchangeable. The differences are not just headline rates: registration, filing, invoicing, input tax recovery and cross-border treatment all differ.
What Are GST and VAT, and Are They Actually Different?
GST and VAT are both designed to tax consumption by applying tax to the value added at different stages of a supply chain.
In Singapore, businesses charge GST on their taxable sales (this is output tax) and pay GST on their own business purchases (this is input tax). Put simply, the business pays IRAS the difference between the output tax it collects and the input tax it can claim back. The Inland Revenue Authority of Singapore explains the basic GST mechanism and how businesses report output and input tax.
Vietnam follows the same broad principle. Under its current VAT framework, VAT is imposed on the added value of goods and services during production, circulation and consumption. The 2026 consolidated Law on Value-Added Tax also sets out the rules for VAT calculation, deduction and refunds.
Singapore GST vs Vietnam VAT: What Do the Rates and Thresholds Look Like?
| Singapore (GST) | Vietnam (VAT) | |
|---|---|---|
| Standard rate in 2026 | 9% | 10% |
| Temporary reduced rate | – | 8% for qualifying supplies from 1 July 2025 to 31 December 2026 |
| Other key rates | 0% and exempt | 0%, 5% and 10%, with 8% temporarily applying to qualifying 10% supplies |
| Key turnover figure | S$1 million | VND 1 billion (under the credit method) |
| Typical filing | Quarterly | Monthly or quarterly depending on the taxpayer |
Singapore’s GST rate has been 9% since 1 January 2024, following the increase from 8% in 2023, according to IRAS.
Vietnam’s VAT system is slightly more complicated in 2026. The standard rate remains 10%, but qualifying goods and services can receive a temporary two-percentage-point reduction to 8% from 1 July 2025 through 31 December 2026.
The reduction does not apply to certain sectors and products. Vietnam’s National Assembly Resolution 204/2025/QH15 sets out the temporary reduction, while the current VAT Law provides the underlying rate structure.
GST and VAT Registration Thresholds
The word “thresholds” refers to two different figures here. Singapore’s threshold decides whether a business must register for GST at all; Vietnam’s decides how VAT is calculated once a business is in the system.
In Singapore, businesses generally have to register for GST when taxable turnover exceeds S$1 million, using the retrospective or prospective tests set by IRAS.
Vietnam’s VND 1 billion (Vietnamese dong) figure is not the direct equivalent of Singapore’s GST registration threshold. Instead, it decides which of Vietnam’s two VAT calculation methods applies.
- Credit Method: VAT Payable = Output VAT − Deductible Input VAT. This is close to Singapore’s mechanism.
- Direct Method: VAT = Revenue × Rate % at the point of sale, with no input deduction.
- Typically used by smaller businesses. Gold, silver and gemstone trading is also taxed under the direct method, on trading margin.
Businesses meeting the relevant accounting and invoicing conditions can also voluntarily apply the credit method under the Vietnam VAT Law.
So How Do the Compliance and Accounting Rules Actually Differ?
GST and VAT Filing Frequency: Monthly vs Quarterly
Singapore’s standard GST accounting period is three months, although businesses can apply for monthly accounting periods in certain circumstances. GST returns and payment are generally due one month after the end of the accounting period, according to IRAS.
Vietnam uses monthly and quarterly filing depending on the taxpayer and its circumstances. From 1 July 2026, Circular 89/2026 introduced updated rules affecting the determination of filing periods, including for newly established enterprises. Ernst & Young (EY) Vietnam’s 2026 tax update explains the changes.
For a finance team operating across both markets, this means separate filing calendars may be needed even when the underlying business activity is similar.
E-Invoicing: Singapore InvoiceNow vs Vietnam E-Invoicing
Vietnam has a particularly strong focus on electronic invoicing. Broad mandatory e-invoicing has been in place since 1 July 2022, with additional requirements introduced through Decree 70/2025 from 1 June 2025. the guidance on the invoicing changes explains the additional rules.
Singapore is moving in the same general direction through InvoiceNow, its nationwide e-invoicing network, but on a phased timetable. The requirement phases in as follows:
| GST InvoiceNow requirement | Who it applies to |
|---|---|
| From 1 Apr 2026 | Businesses applying for new voluntary GST registration |
| From 1 Apr 2028 | New compulsory registrants, plus existing GST-registered businesses with annual supplies of S$200,000 or less |
| From 1 Apr 2029 | Existing GST-registered businesses with annual supplies of more than S$200,000 up to S$1 million |
| From 1 Apr 2030 | Existing GST-registered businesses with annual supplies of more than S$1 million up to S$4 million |
| From 1 Apr 2031 | Existing GST-registered businesses with annual supplies of more than S$4 million |
IRAS sets out the implementation timeline.
In practice, tax compliance is increasingly tied to the accounting and invoicing systems a business uses, not just handled at filing time.
Input Tax Credits and Zero-Rated Supplies
The basic idea is the same in both markets: qualifying input tax can usually be credited against output tax.
In Singapore, you can claim input GST if you are registered, use the goods or services for business, and keep the required documents. IRAS guidance on input tax claims sets out the conditions.
- Zero-rated: The supply is still taxable, but at 0%, such as qualifying exports. You charge no tax, but you can still claim back the input tax you paid.
- Exempt: No tax is charged at all, and input tax on those exempt sales generally cannot be claimed back.
In practice, zero-rated supplies stay taxable and the related input GST is claimable, while input tax on exempt supplies is restricted. A business with S$100,000 of zero-rated export sales and S$9,000 of related input GST can claim the full S$9,000; if those sales were exempt instead, the S$9,000 would generally be blocked. IRAS’s guidance on exempt supplies explains the distinction.
Vietnam applies a 0% rate to qualifying exports and has its own rules for input VAT deduction. The current VAT Law sets out the documentation and payment conditions you must meet to support a deduction.
GST and VAT Refunds for Overseas Businesses
Refunds work differently in the two markets. Singapore handles eligible refunds through the GST return. Vietnam has more specific refund categories, mainly qualifying exports and investment, and updated its refund framework on 1 January 2026 (Law 149/2025). PwC Vietnam’s 2026 VAT update outlines the changes.
A simple example: if a Singapore business charges S$9,000 of GST on its sales but incurs S$12,000 of qualifying input GST in a quarter, its GST return shows a S$3,000 refund. Vietnam works similarly for qualifying exporters, who can claim back input VAT paid on materials for goods sold at 0%, subject to documentation and payment conditions.
Cross-border transactions need similar care. In Singapore, a reverse charge applies to certain imported services and low-value goods: the Singapore customer, not the overseas supplier, accounts for the GST to IRAS. Overseas suppliers of qualifying business-to-consumer (B2C) supplies can fall under the Overseas Vendor Registration regime. IRAS’s overseas business guidance explains when these apply.
Vietnam has its own rules for foreign suppliers, those without a permanent establishment in Vietnam under Decree 181/2025. These suppliers, including those selling through e-commerce and digital platforms, must register and declare VAT through the tax authority’s online portal. Foreign digital platform operators can be required to withhold and pay the tax on their behalf. These rules sit within the broader Vietnamese VAT framework.
What Does This Mean for Businesses Operating in Both Markets?
For a Singaporean business expanding into Vietnam, the biggest mistake would be assuming that an existing Singapore GST process can simply be copied into the Vietnamese entity.
The finance team may face different tax rates, invoice requirements, filing periods and documentation rules for input tax claims. Cross-border transactions may also need a separate review depending on where the supplier, customer and transaction are located.
In practice, the important questions are often straightforward:
- Which entity is making the sale?
- What is being supplied?
- Where is the transaction taking place?
- Which VAT or GST treatment applies?
- What documentation is needed to support the tax treatment?
This is also why tax compliance needs to be considered alongside the wider operating setup. United Consulting’s guide to Vietnam tax compliance for small and medium-sized enterprises (SMEs) covers practical issues including expense settlement, VAT and corporate tax deductibility. For the wider entry framework, see our guide to Vietnam’s Law on Investment 2026, and for customer-facing businesses our Vietnam retail market entry in 2026 guide.
Conclusion
Singapore’s GST is currently 9%, while Vietnam’s standard VAT rate is 10%, with an 8% temporary rate applying to qualifying supplies until 31 December 2026. Beyond the headline rates, the bigger differences are found in registration mechanics, filing, invoicing, input-tax recovery, refunds and cross-border transactions.
For businesses operating across Singapore and Vietnam, understanding those differences early can make the tax side of expansion much easier to manage. The same principle applies to other areas of business operations too. Singapore’s CPF and Vietnam’s social, health and unemployment insurance (SHUI) obligations both form part of employment costs, but the systems are structured differently, as we explain in our CPF versus SHUI comparison.
Thinking about entering or expanding in Vietnam? Contact United Consulting to discuss the tax and compliance requirements relevant to your business.
