The Ultimate Guide To GST Registration Singapore

Lydia Chin

9 mins read

Published:

22 May 2025

Updated:

8 December 2025

Once you register, GST filing follows.

In Singapore, GST registration isn’t something to take lightly. Cross S$1 million, and IRAS expects you to act fast.

The problem? Many business owners don’t know when they cross the line or what to do next.

If you’re scaling quickly and unsure if you want to be a GST registered company or what IRAS actually requires, this guide clears up the guesswork. Local SMEs from Clementi to Raffles Place trust it to keep things clean, compliant, and penalty-free, because “I didn’t know” doesn’t cut it with IRAS.

Contact us for GST Registration help

Who needs to register for GST in Singapore?

If your business pulls in more than S$1 million in taxable turnover, GST registration is a must. IRAS expects you to charge GST on your sales and file regular returns once you cross that mark.

Here’s how you might hit the threshold:

Past 12 Months: You’ve already made over S$1 million in the last year. For example, if your revenue from May 2024 to April 2025 hits that number, you must register for GST within 30 days from the end of April.

Next 12 Months (Forecast): You expect to earn more than S$1 million in the coming year. This could be from a big client or a signed contract.

Note: IRAS looks at forecasted revenue too, not just what’s already in the bank.

document.addEventListener("DOMContentLoaded", function() { document.getElementById('scheduleameeting1')?.addEventListener('click', function() { fireEvent('SG_CTA_Popup_Meeting_Resource_Schedule_a_meeting_1'); }); });

Can’t tell if you’re getting close to the threshold? Add up your taxable revenue. This includes local sales, overseas sales billed to Singapore customers, and some imported services. If the total is inching near S$1 million, it's best to start preparing.

Voluntary GST registration: When does it make sense?

Below the compulsory limit? You can still register voluntarily if it benefits your business.

You incur significant GST on expenses: Spending a lot on rent, software, or services? Voluntary GST registration lets you claim input tax and recover GST paid, lowering your costs.
Your clients prefer GST-registered vendors: Some corporates and agencies only work with GST-registered suppliers. Being registered adds credibility and may help you win contracts. It shows you’re compliant and business-ready.
You’re scaling fast: If your revenue’s rising fast and you’ll likely hit the threshold soon, registering early avoids last-minute panic. You’ll stay compliant and avoid penalties for late registration.
You’re in an exempt sector but still incur GST: If you are a GST registered company in an industry like finance or real estate, you can’t charge GST but still pay it on costs. Voluntary registration can allow for partial claims or better tax planning. It’s useful if you mix GST-exempt and taxable activities or are restructuring.

Important: Once you register voluntarily, you must remain registered for at least 2 years. So think long-term before opting in. Read on this guide on voluntary GST registration to learn more.

Special GST registration scenarios

Some businesses may need to register for GST even if they don’t fit the usual S$1 million turnover rule. Here are two common scenarios:

Importing services or Low-value goods (Reverse Charge)

If you’re not entitled to full input tax credit, and you’re:

Buying services from overseas (like software, subscriptions, or consulting)
Importing low-value goods under S$400

You may be subject to reverse charge, meaning you’ll have to account for GST on behalf of the overseas supplier. For instance, financial firms using overseas cloud software often fall under this rule.

Overseas Vendors Selling to Singapore (OVR)

If you’re an overseas business providing:

Digital services (like streaming, apps, or online ads)
E-commerce goods to customers in Singapore

You may need to register under IRAS’s Overseas Vendor Registration (OVR) regime, even without a physical presence in Singapore.

Example: An Australian e-learning platform with $200,000 in sales to Singapore residents via app stores is required to register under OVR.

GST registration in Singapore 2025: Latest rules and deadlines you must know

If your revenue is growing faster than bubble tea queues on a hot day, you might need to register for GST soon. Here’s what you need to know.

When to register for GST in Singapore?

You must register for GST if:

You made more than S$1 million in a calendar year (not the last 12 months — this is the retrospective view), or
You’re very sure you’ll hit S$1 million in the next 12 months (this is the prospective view)

Either way, IRAS gives you 30 days to register. Don’t say bo jio.

Deadlines & Effective Dates

GST registration deadlines for a GST registered company — GST Registration Deadlines

1. Retrospective View

Condition: Your taxable turnover exceeds S$1 million at the end of the calendar year (e.g. 1 Jan – 31 Dec)
Deadline: Register within 30 days from 31 Dec
GST starts on: 1st day of the second month after the year ends
Example: Crossed threshold on 31 Dec 2024 → Register by 30 Jan 2025 → GST effective from 1 Mar 2025

2. Prospective View

Condition: You can reasonably forecast turnover > S$1M in the next 12 months
Deadline: Register within 30 days from your forecast date
GST starts on:
- Before 1 Jul 2025: GST applies from the 31st day after your forecast
- From 1 Jul 2025 onwards: You get a new 2-month grace period, GST kicks in 2 months after the forecast date

Exceptions to GST registration

You might not need to register if:

You only sell zero-rated goods (e.g. exporting like a champ)
You exceeded S$1M in the last calendar year, but if you’re not expected to exceed it in the next 12 months, and can prove a valid reason (like downsizing)

Note: Always keep supporting documents. IRAS may ask for proof!

Missed your deadline? Here’s what you’re risking:

Backdated GST liability – you’ll owe GST on past sales, even if you didn’t charge your customers
Fines up to S$10,000, plus a 10% penalty on unpaid GST
Possible prosecution

Voluntary disclosure may save you from penalties. IRAS might even let you pay in installments. If you need help, use the official IRAS GST Registration Calculator to know your status.

How to register for GST in Singapore

Here’s how to register via IRAS myTax Portal.

Step 1: Confirm eligibility

You must register if:

Your taxable turnover has exceeded S$1 million in the past 12 months
You expect to exceed S$1 million in the next 12 months
You fall under special cases, such as reverse charge or the overseas vendor regime

Step 2: Complete the IRAS e-Learning (for voluntary registration)

If you’re registering voluntarily, IRAS requires you to complete the Overview of GST e-learning course. It covers key topics like GST obligations and how the tax applies to your business.

After completing the course, download your certificate and include it with your application.

Step 3: Prepare your documents

Before applying, gather the following:

Company UEN and registration details
Description of business activities
Financial statements or projected turnover
NRIC or FIN of directors and key personnel
Financial year-end
Company structure, such as sole proprietorship or private limited

For businesses with complex structures or GST schemes like reverse charge, IRAS may request additional documents.

Step 4: Submit your application

Log in to the IRAS myTax Portal using Corppass. Fill out the GST registration form and upload your documents. You can save your progress and return to it later if needed.

Step 5: Wait for approval

IRAS usually processes applications within 10 to 30 working days. They may contact you if they need more information. Once your application is approved, IRAS will provide:

Your effective GST registration date
Your GST registration number

This number must appear on all tax invoices and official documents.

Step 6: Comply with ongoing obligations

Once you receive your GST registration number from IRAS, you’re officially a GST registered company. Here’s what to do next.

Charge GST: Add 9% GST to all taxable sales. Update your invoices to show your GST registration number clearly.
File returns: Quarterly via IRAS myTax Portal, one month after each quarter ends.
Keep records: Store all GST invoices, receipts, and credit notes for five years.
Stay updated: GST rules evolve, especially for e-commerce, overseas vendors, and tech services. Follow IRAS updates regularly or work with a tax professional to stay compliant.

RELATED GUIDE

GST Compliance Guide 2025

How Sleek helps with GST registration in Singapore

Becoming a GST registered company in Singapore can feel like a big task. Between the paperwork, IRAS requirements, and constantly evolving tax rules, it’s easy to feel overwhelmed, especially if you’re doing it for the first time.

Sleek simplifies the entire process by offering clear guidance, hands-on support, and local expertise tailored to your business needs.

Here’s how we make it easier:

Complete registration support
From preparing and submitting the right forms to uploading the required documents and communicating with IRAS, we manage every step for you.
Time-saving convenience
No more Googling how to register or worrying if you missed a detail. You stay focused on running your business, while we handle the admin in the background.
Expert answers, when you need them
Our team of GST professionals is here to explain the process in plain, practical terms and answer any questions along the way. If something doesn’t make sense, we’ll walk you through it.

Whether you’re just crossing the S$1 million threshold or voluntarily willing to be a GST registered company, Sleek is here to help you do it right, without the stress or uncertainty.

Ensure accurate, timely GST registration with Sleek

FAQs about GST registration in Singapore

When must my business register for GST in Singapore?

You must register for GST when your taxable turnover exceeds S$1 million over the past 12 months, or if you expect to cross that amount in the next 12. This is a requirement under IRAS rules. Registration must be done within 30 days of meeting this threshold.

Can I register for GST even if my revenue is under S$1 million?

Yes, GST registration is available even if you haven’t hit the compulsory turnover level yet. It can help you claim input tax on business expenses and boost your company’s credibility. Once registered, you must comply with GST filing and record-keeping obligations.

What are the benefits of voluntary GST registration?

Voluntary registration lets you claim back GST paid on expenses, manage cash flow better, and appear more established. It’s especially useful if you deal with GST-registered clients or suppliers. Keep in mind that once you register, you must stay in the scheme for at least two years.

What happens if I don't register for GST when required?

If you’re required to register and fail to do so, IRAS may impose penalties and backdate your registration. You could be liable for GST on past sales, even if you did not collect it. It’s important to register on time to avoid unnecessary costs.

What documents do I need to register for GST?

You’ll need your company UEN, financial statements or projected revenue, business activity details, and director identification. Voluntary applicants must also complete the IRAS Overview of GST e-learning course and include the certificate with their application.

How long does GST registration take in Singapore?

IRAS usually processes GST applications within 10 to 30 working days. The timeline may vary depending on your business structure and whether additional documents are needed. IRAS will notify you once your registration is approved and provide your GST number.

What do I need to do after registering for GST?

After registering, you must charge 9% GST on taxable sales, issue tax invoices with your GST number, and file GST returns every quarter. You must also keep your records for at least five years to stay compliant with IRAS requirements.

What if my turnover drops below S$1 million after I register?

If your turnover stays below S$1 million for 12 months, you may apply to deregister. IRAS will assess whether your future revenue will remain below the threshold. For voluntary registration, you must stay registered for at least two years before applying to cancel.

Who needs to register under the reverse charge or overseas vendor regime?

You must register under reverse charge if you import services or low-value goods and cannot fully claim input tax. Overseas vendors selling digital or physical goods to Singapore customers may also need to register under IRAS’s Overseas Vendor Registration (OVR) scheme.

Do freelancers or sole proprietors need to register for GST in Singapore?

Yes. GST registration depends on your annual taxable turnover, not your business type. Freelancers and sole props are subject to the same revenue rules. If your earnings cross the limit, GST registration applies. Voluntary registration is also an option if you’re below the threshold and want to claim input tax.

For a deeper dive, check out our full guide: 7 Essential GST Tips for Freelancers in Singapore