
Before buying anything: Singapore’s tap water is already safe to drink straight from the tap, without boiling or filtering — PUB runs over 500,000 water quality tests a year and the supply meets WHO Guidelines. A filter here solves taste, chlorine smell, or building-specific plumbing issues, not a safety gap. With that framed correctly, here are real products by tier, with pricing and trade-offs for each.
Quick answer: For a simple chlorine-taste fix, the 2-Stage Under Sink Filter (~S$41). For NSF-certified reassurance without RO, the 3M™ AP Easy Complete (~S$599). For full reverse osmosis with alkaline remineralisation at the best price, the iSpring RCC7AK (~S$479). Skip the S$3,000+ tier unless alkaline/ionised water is a specific lifestyle choice.
Do You Actually Need One?
- You dislike the chlorine taste/smell — a basic carbon filter solves this well and cheaply
- You want reduced water hardness or dissolved solids — reverse osmosis addresses this, though it strips beneficial minerals unless the system reintroduces them
- You’re on old plumbing or an ageing building water tank — filtering can address building-specific taste/sediment issues
- You just want peace of mind — valid preference, but not addressing an actual safety gap
Real Products, Compared
1. 2-Stage Under Sink Filter — Budget
| Price | ~S$40.70 |
| Filter type | Carbon |
| Installation | Wall-mountable, DIY, no plumber typically needed |
| Best for | Simple chlorine taste/odour removal on the lowest budget |
- Cheapest way to fix chlorine taste
- Simple DIY install
- No RO/mineral filtration — taste-only fix, not hardness or dissolved solids
This is the right starting point for most people, honestly — if the only thing bothering you is the faint chlorine smell, spending more on RO or alkaline systems buys you filtration you probably don’t need. Start here, and only upgrade if taste alone doesn’t solve your actual complaint.
2. PureDrop F3-CUW4 — Budget-Mid
| Price | ~S$71.24 |
| Filter type | 3-stage carbon |
| Installation | DIY-install territory |
| Best for | A modest step up from entry-level with more filtration stages |
- More filtration stages than the cheapest option for a small price increase
- Still carbon-only, no RO capability
The extra filtration stages here mainly buy you finer sediment removal on top of taste — worth the roughly S$30 premium over the 2-Stage option if your water sometimes runs slightly cloudy, but not a meaningfully different product otherwise.
3. PUCRT 100GPD Reverse Osmosis — Mid-RO
| Price | ~S$210.23 |
| Filter type | Reverse osmosis |
| Claimed performance | Removes up to 99% of contaminants (manufacturer claim) |
| Best for | RO-level filtration below the premium price bracket |
- Lower price than most RO systems
- Addresses dissolved solids/hardness, not just taste
- RO strips minerals along with contaminants unless paired with remineralisation
This is where the decision actually gets interesting — RO systems remove far more than carbon filters, but the trade-off is that “removes up to 99% of contaminants” also means removing minerals your body would otherwise get from drinking water. If that matters to you, look at the remineralising option below instead.
4. iSpring RCC7AK — Best Value RO
| Price | ~S$478.98 |
| Filter type | 6-stage RO with alkaline remineralisation |
| Best for | Full RO filtration without the S$3,000+ premium tier |
- Remineralisation addresses the common RO complaint of stripping beneficial minerals
- Strongest value-for-features pick under S$500
- 6-stage system means more cartridge types to track and replace over time
This is the one to buy if you’ve decided you actually want RO — it solves the mineral-stripping problem the cheaper PUCRT system doesn’t address, at under half the price of the premium alkaline ionizer tier below. For most people who’ve concluded a basic carbon filter isn’t enough, this is the sensible stopping point rather than jumping straight to a S$3,000+ system.
5. 3M™ AP Easy Complete — Mid, NSF-Certified
| Price | ~S$599 |
| Filter type | Carbon, NSF-certified |
| Best for | Documented independent certification without going full RO |
- NSF certification means claims are independently tested, not just marketing copy
- Trusted, established brand
- Priced above simpler carbon options for the same core function (taste/odour removal)
You’re paying a premium here specifically for the NSF certification and the 3M name — if independent verification of performance claims matters more to you than saving money, this earns its higher price over an uncertified carbon filter that might make similar claims without the testing to back them up.

6. novita Under Sink Filtration System — Mid-Premium
| Price | ~S$465 |
| Filter type | Carbon with replacement timer |
| Best for | Households that don’t want to manually track cartridge replacement schedules |
- Built-in timer removes the guesswork on when to replace the cartridge
- Carbon-only — no RO/mineral filtration despite the mid-premium price
The replacement timer is a genuinely useful convenience feature that’s easy to underrate — forgetting to change a cartridge means drinking through an exhausted filter for weeks without realising it, so this solves a real (if unglamorous) problem, even though the underlying filtration is no more advanced than a cheaper carbon system.
7. KYK Generation II Alkaline Water Ionizer — Premium
| Price | ~S$3,599 |
| Filter type | Alkaline ionised |
| Certification | FDA-certified as a medical device — an unusual claim for a consumer water product |
| Best for | Buyers specifically wanting alkaline/ionised water as a lifestyle choice |
- Genuine medical-device certification, not a common claim in this category
- Given Singapore tap water is already safe, this tier is a lifestyle purchase, not a necessity
- Highest price point by a wide margin
Be clear-eyed about what you’re buying here: the FDA medical-device certification is real and unusual for this category, but it doesn’t change the fact that Singapore tap water was already safe before it reached this filter. This is a wellness/lifestyle purchase for people who specifically want alkaline water’s claimed benefits, not a step up in basic safety over the S$479 RO system above.
Filter Types Explained
| Type | What it removes | Typical Price |
|---|---|---|
| Carbon filter | Chlorine taste and odour, some sediment | S$40-S$100 |
| Multi-stage (carbon + sediment) | Taste, odour, finer sediment | S$100-S$600 |
| Reverse osmosis (RO) | Dissolved solids, sodium, most minerals | S$210-S$500 |
| Alkaline / ionised | Adjusts pH, reintroduces minerals post-RO | S$465-S$3,600+ |
Ongoing Costs Nobody Mentions
Filter cartridges need replacing every 3-12 months depending on the system and household usage. Carbon cartridges are cheapest to replace; RO membrane and multi-stage sets cost more per swap. Check what a full year of replacement cartridges actually costs before buying — a cheap upfront system with expensive, frequent cartridge changes can cost more over 2-3 years than a pricier system with cheaper, less frequent replacements.
Frequently Asked Questions
What is the best under sink water filter in Singapore?
For most households, the iSpring RCC7AK (~S$479) offers the best balance of reverse osmosis filtration and alkaline remineralisation without premium pricing. For a simple chlorine-taste fix, a basic 2-Stage carbon filter (~S$41) is enough.
Is Singapore tap water safe to drink without a filter?
Yes. PUB conducts over 500,000 water quality tests annually and Singapore’s tap water meets WHO Guidelines for Drinking-Water Quality — safe to drink directly from the tap without boiling or filtering.
Do I need an under sink water filter in Singapore?
Not for safety — the water is already safe. A filter is worth it for chlorine taste/odour, reduced water hardness, or building-specific plumbing taste issues, but it’s a preference upgrade, not a safety necessity.
Is reverse osmosis worth it if Singapore tap water is already safe?
RO is about taste, hardness, and dissolved solids reduction, not making unsafe water safe. If those aren’t concerns for you, a simple carbon filter for chlorine taste is sufficient and considerably cheaper.
How often do I need to replace the filter cartridge?
Typically every 3-12 months depending on filter type and usage. Check the ongoing cartridge cost before buying — cheap filters with frequent expensive replacements can cost more over time than pricier systems with lower running costs.