How Much Does a Reverse Osmosis System Cost in Melbourne? (Installed Price Guide)
How Much Does a Reverse Osmosis System Cost in Melbourne? (2026 Guide)
A 7-stage under-sink reverse osmosis system in Melbourne costs from $1,100 fully installed, including GST. Here’s the full breakdown: what’s included, ongoing costs, and how it compares to bottled water.
$ 50 OFF
Your First Service
10% OFF
Seniors Discount
Free CCTV
Drain Inspection
From $99
Blocked Drains
Understanding the Cost of Reverse Osmosis Systems in Melbourne
Our 7-stage under-sink reverse osmosis system is fully installed for $1,100 including GST. That’s the full, walk-away price: the RO system, all seven cartridges, dedicated drinking water tap, pressurised storage tank, and licensed plumber installation at your Melbourne home.
No separate plumber fee. No hidden call-out charge. No surprise add-ons. The price you’re quoted is the price you pay. Below, we break down exactly what’s included, what ongoing maintenance costs are, and how the numbers compare to what you’re probably spending on bottled water. For more on how the system works, see: What Is Reverse Osmosis and How Does It Work?
What’s Included in the $1,100 Installed Price?
Every under-sink reverse osmosis installation includes:
Included in $1,100 | Status |
7-stage reverse osmosis system (complete unit) | ✓ Included |
All 7 filter cartridges (sediment, dual carbon, RO membrane, post-carbon, alkaline mineral restoration, hydrogen enrichment) | ✓ Included |
Pressurised storage tank | ✓ Included |
Dedicated drinking water tap (installed through benchtop) | ✓ Included |
All fittings, tubing, and connections | ✓ Included |
Licensed plumber installation (1–2 hours) | ✓ Included |
Benchtop drilling for a dedicated tap | ✓ Included |
System testing and flush | ✓ Included |
Handover and operation walkthrough | ✓ Included |
There are no extras to buy separately. You don’t purchase the system from one supplier and then find a plumber to install it. We supply and install as a single service one point of accountability, one price.
Get Your Installed Price Tell us your suburb, and we’ll confirm whether the standard $1,100 covers your installation, or if any extras apply. Upfront pricing, no obligation. ☎ 0420 646 641 | Get a Quote → |
What Could Add to the Cost?
In most Melbourne kitchens, the standard $1,100 covers everything. But some situations may require additional work:
Scenario | Additional Cost | How Common? |
Non-standard benchtop material (e.g., thick stone, engineered stone) requiring specialised drilling | $50–$150 | Uncommon most benchtops are straightforward |
Limited under-sink space requiring reconfiguration of waste pipes or relocation of the storage tank | $100–$300 | Occasional some older Melbourne kitchens have tight under-sink cabinets |
No cold water isolation valve under the sink (needs to be fitted) | $80–$150 | Rare in modern homes, more common in pre-1980s homes |
Adding a whole-house filter at the same time | Additional $1,100 ($2,200 total for both systems) | Very common, many customers install both for complete home coverage |
Any additional work is discussed and priced before we start. There are no surprises after the fact.
Ongoing Costs: What You’ll Spend After Installation
A reverse osmosis system has ongoing maintenance costs, but they’re modest and predictable:
Component | Replacement Frequency | Approximate Cost | DIY or Plumber? |
Stage 1: Sediment pre-filter | Every 6–12 months | $15–$30 | DIY |
Stages 2–3: Carbon pre-filters (GAC + CTO) | Every 6–12 months | $30–$60 | DIY |
Stage 4: RO membrane | Every 2–3 years | $80–$120 | DIY |
Stage 5: Post-carbon polishing filter | Every 12 months | $15–$25 | DIY |
Stages 6–7: Alkaline + hydrogen filters | Every 12 months | $40–$60 | DIY |
Typical annual maintenance cost | $150–$250/year | All DIY |
Every replacement is DIY, no plumber required, for any cartridge or membrane change. The RO membrane is the most expensive single component, but it only needs replacing every 2–3 years. Averaged out, your total annual maintenance cost is approximately $150–$250, or roughly $13–$21 per month for purified drinking water on demand.
RO System vs Bottled Water: The 10-Year Cost Comparison
This is the comparison that makes the financial case undeniable:
Bottled Water (Family of 4) | Under Sink RO System | |
Year 1 | $1,500–$2,500 | $1,100 (installation) + ~$200 (cartridges) = $1,300 |
Year 2 | $1,500–$2,500 | ~$200 |
Year 3 | $1,500–$2,500 | ~$300 (includes membrane replacement) |
Years 4–10 (7 years) | $10,500–$17,500 | ~$1,600 (annual cartridges + one more membrane) |
10-Year Total | $15,000–$25,000 | ~$3,400 |
10-Year Savings with RO | $11,600–$21,600 |
Even at the conservative end, a family switching from bottled water to an RO system saves over $11,000 across 10 years. At the higher end, it’s over $21,000. The system pays for itself within the first 6–12 months, and every year after that is pure savings.
And the water quality from an RO system is typically better than most bottled brands, which are often just filtered municipal water in a plastic bottle.
Pricing Compared: RO, Whole House, or Both
We offer two filtration systems. Here’s how the pricing works across all three options:
Under Sink RO (7-Stage) | Whole House Carbon (HP3) | Both Systems | |
Installed price | From $1,100 | From $1,100 | From $2,200 |
Annual maintenance | ~$150–$250 | ~$350/year (cartridge set) | ~$500–$600/year |
Filtration level | 0.0001µm (molecular) | 0.5µm (sub-micron) | Both levels |
Coverage | Kitchen drinking tap only | Every tap, shower, appliance | Complete home + purest drinking water |
Removes fluoride? | ✓ Yes | ✗ No | ✓ Yes (at kitchen tap) |
Best for | Purest drinking water, fluoride removal, dissolved contaminant removal | Clean water at every tap, chlorine/chloramine removal for the entire home | Complete home water treatment the most comprehensive option |
0% finance is available on all options. Not sure which setup is right for your home? Reverse Osmosis vs Carbon Filter explains the technical difference, and our Whole House vs Under Sink comparison covers the practical decision. For the whole house system’s cost breakdown, specifically, see our whole house water filter cost guide
Why Supply-and-Install Beats Buying Online
You can buy a reverse osmosis unit online for $300–$800. That looks cheaper until you factor in what’s missing:
Buy Online + Separate Plumber | Select Plumbing Supply & Install | |
System cost | $300–$800 | Included in $1,100 |
Plumber installation | $300–$500 (separate booking, separate cost) | Included in $1,100 |
Dedicated drinking tap + benchtop drilling | May not be included additional $50–$150 | Included |
System quality (number of stages) | Typically 4–5 stages. No mineral restoration. No hydrogen enrichment. | 7 stages, including alkaline mineral restoration and hydrogen enrichment |
Warranty and accountability | Split: manufacturer warranty on product, no warranty on installation quality | Single point of accountability for product and installation |
Total realistic cost | $650–$1,450+ (for a lesser system) | $1,100 (for a superior system, fully installed) |
The supply-and-install model removes the guesswork. You’re not researching which system is compatible with your plumbing, which tap fits your benchtop, or whether the plumber you’ve booked has experience with RO installations. We handle the entire process as a single service.
0% Finance Available
We offer 0% interest finance on all water filter installations. This means you can spread the cost of a $1,100 RO system, a $1,100 whole house filter, or the $2,200 dual-system package across manageable repayments with no interest charged. Ask us for details when you call.
Frequently Asked Questions
How much does it cost to install a reverse osmosis system in Melbourne?
Our 7-stage under-sink reverse osmosis system is fully installed for $1,100 including GST. This includes the system, all cartridges, dedicated drinking tap, storage tank, and licensed plumber installation. Additional costs may apply for non-standard benchtop materials or limited under-sink space, but these are discussed and priced before any work begins.
How much does RO maintenance cost per year?
Approximately $150–$250 per year. This covers replacement pre-filters (every 6–12 months), post-filters (annually), and the RO membrane (every 2–3 years, averaged out). All replacements are DIY and therefore, no plumber is needed.
Is reverse osmosis cheaper than bottled water?
Significantly. A Melbourne family of four spends approximately $1,500–$2,500 per year on bottled water. An RO system costs $1,100 to install and approximately $200 per year to maintain. It pays for itself within 6–12 months, and over 10 years saves $11,000–$21,000 compared to bottled water.
Can I install a reverse osmosis system myself to save money?
While some online systems are marketed as DIY, professional installation ensures correct connection to your water supply, proper benchtop drilling for the dedicated tap, leak-free fittings, and compliance with Australian plumbing standards. Incorrect installation can cause leaks, water damage, or a system that doesn’t function properly. Our installation is included in the price, so there’s no saving to be made by going DIY.
Should I get RO, a whole-house filter, or both?
It depends on your priorities. RO gives you the purest possible drinking water (including fluoride removal) at the kitchen tap. A whole-house filter gives you chlorine-free, chemically filtered water at every tap, shower, and appliance. Both together give you complete home coverage.
Do you offer finance for water filter installations?
Yes. We offer 0% interest finance on all water filter systems, including the under-sink RO, whole house filter, and the combined dual-system package. Ask us for details when you get in touch.
Understanding the Cost of Reverse Osmosis Systems in Melbourne
