When do I actually need to register for GST as a small business?

Ran a small online biz through this. The core rule: GST registration is compulsory once your taxable turnover crosses the prescribed threshold (on a rolling 12-month basis, or if you reasonably expect to exceed it). Below that, it's voluntary. Key considerations: 1) compulsory, watch your rolling 12-month revenue, once it's heading past the threshold you must register within the required window or face penalties, 2) voluntary early registration, worth it only if you sell mostly to GST-registered businesses (they claim it back) or have big input GST to reclaim, otherwise you're just adding 9% that makes you pricier to consumers, 3) registering means you charge GST, file returns, and keep proper records, more admin. For a consumer-facing store, most people wait until they must. Track your trailing 12-month turnover monthly so you don't cross unknowingly. Please verify the current GST threshold, rate, and timelines on the IRAS website, these figures do change.

Once you're registered, be aware it's meaningfully more admin, ongoing, you'll be filing GST returns periodically (typically quarterly), keeping proper tax-compliant records of every transaction, and correctly charging, collecting and tracking the GST on sales as well as claiming it on purchases, all of which is real recurring work or an accounting cost. So don't volunteer yourself into that overhead before you actually have to, unless the input-tax reclaim genuinely outweighs the hassle for your specific situation. For a growing consumer store, the sensible play is usually to keep tracking your rolling turnover and register only when you're legally required to, then treat the admin as a cost of that growth. And do confirm the current threshold and the GST rate directly on IRAS, because they've been changing in recent years and I don't want to quote you a stale number.

Voluntary early registration mostly makes sense only if your customers are other GST-registered businesses who simply claim the GST back, so charging it doesn't actually cost them anything, meanwhile you get to reclaim the GST on your own inputs. But if you sell to normal everyday consumers, which most online stores do, registering early just makes your prices effectively 9 percent higher, or eats into your margin if you absorb it, with no upside, because your customers can't claim anything back and just see a pricier product. So the key question isn't your revenue, it's WHO your customers are. I waited until registration was compulsory for exactly this reason, no point handicapping myself on price voluntarily. Think hard about your customer base before volunteering, it's often the wrong move for a consumer-facing shop.

Watch the rolling 12-month turnover, not the calendar year, because that's the exact mistake that catches small business owners off guard, they think in Jan-to-Dec terms while the compulsory-registration test looks at any trailing 12-month window. So a strong few months can push your rolling total past the threshold mid-year without you noticing if you're only glancing at annual figures. Once you can reasonably see you'll cross it, you must register within the required timeframe, otherwise IRAS can backdate your registration and hit you with penalties for the GST you should have been charging. My habit is a simple spreadsheet with a running 12-month total that I update every month, so I always know exactly how close I am. Set that up now while you're growing, so the threshold never sneaks up on you.