Water Purifier Buying Guide India 2026: RO vs UV vs UF, TDS and Real Cost

Short answer: test your water TDS first, pick RO only if your water needs it, and judge a purifier by its 5-year cost, not its price tag. A simple, open design that any technician can repair beats a sleek sealed one. Ready to buy? Jump to our top 8 water purifiers.

Geekman has covered consumer tech for over 10 years, and this guide is built the way our buying guides always are: research first, then a hard look at the numbers. I have used purifiers from Urban Company Native, Atomberg and KENT myself. For the rest I compared official specs, warranty terms, service plans and live prices. This guide has no sponsor. No brand paid to be in it.

The big question

Do you really need RO in India?

Short answer: in most Indian homes, yes, you need more than a plain filter. Not because every tap is bad, but because you cannot tell by looking, tasting or using a TDS meter. If a lab report says your water is clean and low in TDS, UV + UF can do the job. If you do not know, assume you need RO + UV.

Here is the part that surprises first-time buyers. TDS is like the number on a bathroom scale. It tells you how heavy, not what the weight is made of. 70 kg of muscle and 70 kg of samosas read the same. A TDS meter does this with water: it counts everything dissolved, but it cannot tell harmless calcium from fluoride or nitrate.

What can hide in Indian water

What	Where it shows up	Seen by a TDS meter?	What helps
Fluoride	Natural, in groundwater. Rajasthan, Gujarat and Telangana stand out in the 2025 CGWB report	No	RO
Arsenic	Groundwater in the Ganga and Brahmaputra basins	No	RO
Nitrate	The most common problem: about 21% of tested groundwater samples crossed the limit	Not on its own	RO
Uranium	Localised, mostly in Punjab and Haryana	No	RO
Bacteria and viruses	Leaky pipes, dirty tanks, stored water	No	UV or UF
Pesticides and chlorine taste	Farm run-off, treated tap water	No	Carbon filter, RO

RO reduces these a lot, but it does not promise zero. Your lab report shows what is in your water, and the purifier maker states what it is tested for.

It is not just groundwater

In 2019 the Consumer Affairs Ministry had the BIS test tap water in 21 state capitals. Only Mumbai passed every test it was checked on. All 11 samples from Delhi failed, and several other capitals had at least one failing sample.

More recently, in December 2025, sewage leaked into a municipal pipeline in the Bhagirathpura area of Indore. The result was a diarrhoea outbreak. Early reports counted at least nine deaths and more than 200 people in hospital, and later counts were higher. A purifier does not replace a safe supply. But UV, UF and RO stages exist to stop exactly this kind of germ at your tap.

So, do you need RO? A simple way to decide

TDS above 500, or borewell and tanker water: yes. Get RO + UV, and add a pre-filter.

You do not know what is in your water: treat it as a yes until a lab test says otherwise. RO + UV with TDS control is the safe default.

Municipal water, TDS under 200 and a clean lab report: no. UV + UF is enough, and it wastes no water.

Supply that changes through the year: an adaptive purifier that reads TDS and switches modes, like some of our top picks.

Sources: Central Ground Water Board Annual Groundwater Quality Report 2025 (summary), BIS tap water tests of 2019, Indore contamination report.

Start here

The 60-second decision

Most people buy a purifier the wrong way round. They look at the brand, then the price, then maybe the water. Do it the other way. Your water decides the technology, and the service cost decides which purifier is really cheaper.

Step 1

Know your water before you shop

TDS stands for Total Dissolved Solids. It is the total of salts and minerals dissolved in water, shown in ppm (parts per million), which is the same as mg/L. A pen-sized TDS meter costs a few hundred rupees. Dip it in, wait a few seconds, read the number. Test every source you use: municipal tap, borewell and tanker can all be very different.

Your TDS	What it usually means	What to look for
Under 200 ppm	Soft, clean municipal water	UV + UF can work. An adaptive purifier is a smart option.
200 to 500 ppm	Typical city tap water	RO with TDS control, or an adaptive RO purifier.
Above 500 ppm	Borewell and tanker water	Full RO is needed. Check the purifier’s maximum TDS rating.
Above 2,000 ppm	Very hard or salty water	Only models rated for it. Ask the maker before you buy.

The Indian drinking water standard, IS 10500, gives 500 mg/L (ppm) as the acceptable limit for TDS. It allows up to 2,000 mg/L only where no better source exists. It has no minimum value.

What a TDS meter cannot tell you

You will hear advice like “your TDS is 180, you do not need RO, just buy UV”. It sounds neat, and sometimes it is right. But a TDS meter only counts how much is dissolved. It does not say what it is. Lead, arsenic, fluoride and nitrate can be present in water that reads a low number, and they matter even in small amounts. UV and UF do nothing about them.

When to get a lab test (₹500 to ₹1,500)

Get a basic water test done if you use borewell or hand-pump water, if your area is known for fluoride or arsenic in groundwater, or if the water leaves stains or an odour. Parts of Rajasthan, Gujarat, West Bengal, Punjab and Uttar Pradesh have well-documented problems of this kind. One lab report gives you clarity for years, and it stops you from guessing.

Hard water and scale

High TDS water is often hard water. Hardness builds scale on the RO membrane and inside the tank and shortens filter life. Borewell and tanker users should add a pre-filter (more on that below) and pick a model rated for their TDS.

Step 2

RO, UV and UF: what each one actually does

Think of them as three different jobs. RO handles what is dissolved in the water. UV handles germs. UF is a fine sieve for particles and bacteria. Each one covers a gap the others leave.

For most Indian homes, an RO + UV + UF combination is the safe choice. RO deals with salts and metals, UV and UF cover germs. If you are on clean municipal water with confirmed low TDS and a clean lab report, UV + UF alone can work, and you avoid the water waste and the stripped minerals.

Adaptive purifiers are the newer idea. Models like the Atomberg Intellon and the Urban Company Native read your input TDS and change how hard they work. If your water swings between municipal supply in the monsoon and borewell in summer, that flexibility is genuinely useful. Our best water purifier ranking covers how each one handles it.

Is RO water bad for you?

You may have heard that RO water is “dead water”. The honest answer is that it is not settled. Here are the facts as they stand.

What RO does: it removes most dissolved solids, including calcium and magnesium. Household RO output is often very low in TDS.

What experts say: WHO has no health-based limit for TDS and calls water under 300 mg/L excellent for taste. Some Indian doctors and researchers want more study on very low TDS water. Other experts say most of your minerals come from food, not water.

What the rules say: in 2019 the National Green Tribunal told the government to restrict RO where TDS is below 500 mg/L and to push for at least 60% water recovery. The Supreme Court stayed that order in 2022. New rules on water purification systems followed in 2023.

What I suggest: use RO where your water needs it, add a mineral cartridge or TDS controller so the output sits around 50 to 150 ppm, and skip RO when a clean lab report says you do not need it.

Step 3

The real cost of a water purifier in India

This is the part nobody puts on the box. A purifier costs about ₹12,000 to ₹18,000 to buy. Then comes service, filters and AMC of roughly ₹3,000 to ₹6,000 a year. Over five years, the price you paid is only about a third of what you spend.

	Purchase	Yearly cost	5-year total
Brand AMC every year	₹15,000	About ₹4,000	About ₹35,000
Self-managed, open design	₹15,000	About ₹2,000	About ₹25,000
Long free-service plan	₹18,000	About ₹2,250 after year 2	About ₹24,750

These are examples to show how the maths works, using typical prices. Your numbers will differ. Always ask the seller for the 5-year number.

How much does water purifier AMC cost?

For many brands the purifier is the starting point and the service plan is where the money is. Yearly plans typically range from about ₹2,000 to ₹6,000. Further down, the brand ranking is built around this number.

Brand	Typical yearly AMC	Good to know
Urban Company Native	None for 3 years	Current models run three years service-free. After that, fixed renewal pricing.
Atomberg	No AMC for 2 years	After that you pay mostly for parts that actually wear out.
KENT	₹3,500 to ₹5,000	Very wide service reach. Plans often leave out the membrane and pump. Easy to service through a local technician.
Aquaguard (Eureka Forbes)	₹3,000 to ₹5,800	Strong in metros. Several plan tiers, so read the inclusions.
Havells	₹2,500 to ₹4,500	Filters are not always covered.
Livpure	₹2,000 to ₹3,500	Lowest AMC of the big names. Service speed varies by city.
Pureit (HUL)	₹3,500 to ₹5,000	Pan-India reach. Full plans sit at the higher end.
Blue Star	₹2,500 to ₹4,000	Reliable service in many cities.
AO Smith	₹3,500 to ₹6,000	Premium pricing and limited reach in small towns.

Ranges are typical figures from brand plans and price guides, not quotes. Plans change, so ask for the current price in writing.

What the fine print hides in AMC plans

Many “comprehensive” plans leave out the two costliest parts: the RO membrane (₹1,200 to ₹2,500) and the pump (₹1,500 to ₹2,500). “Free service in year one” often means free labour, with filters charged on top. Before you sign, ask what is excluded, how many visits you get, and what a membrane replacement costs.

The dealer will push the model with the best margin

Local dealers often recommend whatever pays them the most. Ask them for the model’s filter life in litres, the warranty exclusions and the price of the next filter set. If the answers are vague, walk away.

Step 4

Why a simple, open design saves you thousands

This is the advice I rarely see anywhere else. Open the top cover or back panel of the purifier at the shop, or watch a teardown video. Can you see the filters? Are the tubes held by push-fit connectors? Could a local technician swap a filter without special tools? If yes, you will never be trapped by brand-only service. If everything is crammed, sealed and proprietary, you will pay brand rates for the life of the machine.

	Open, standard design	Sealed, proprietary design
Visit cost	₹200 to ₹400 for a local technician	₹800 to ₹1,500 or more for a brand visit
Inline filter	₹50 to ₹150 aftermarket	₹200 to ₹500 brand-only
RO membrane (80 GPD)	₹800 to ₹1,200	Brand price, often higher
Upgrades later	Add a mineral or copper cartridge for ₹200 to ₹500	Usually not possible

Typical market prices. A compact, sleek purifier is not bad, but it is harder and dearer to service. If you choose one, pick a brand with a clear fixed-price service plan, as some of our top picks have.

What you can do yourself, and what needs a technician

You can usually change inline filters (sediment, carbon, UF, mineral) yourself in about five minutes: pull the tube, swap the filter, push the tube back. An RO membrane swap is a bit more involved but doable. Electrical faults, such as the adapter, pump or UV lamp, need a technician. Always switch off and close the inlet valve first.

A quick check before you buy

Ask the seller whether aftermarket filters fit. Ask for the filter change steps of that exact model. If the seller can describe a quick DIY change, the design is friendly. If only a brand technician can do it, treat that as a warning.

Step 5

Filters, membrane and pre-filter

Brands quote filter life in months. Ask for litres instead, because that is what actually wears a filter out. A sediment filter often handles around 4,000 to 6,000 litres and an RO membrane around 6,000 to 12,000 litres. A 12,000 litre membrane gives you roughly two years for a family using 15 litres a day. Several newer models, including some from Urban Company Native and Atomberg, advertise long-life filters of this kind.

Do you need a pre-filter?

A pre-filter costs about ₹300 to ₹500 and sits before the purifier. It catches sand, rust and mud so the filters inside last longer. For borewell and tanker water, I treat it as essential. Without it, sediment can clog the inner filters in weeks. For cleaner municipal water it is a cheap bonus.

Step 6

Tank, TDS controller and mineral cartridges

Steel tank or plastic tank

A stainless steel (304 grade) tank is more durable and stays fresher in an Indian summer above 40°C. Food-grade ABS plastic is safe, lighter and cheaper. It can pick up fine scratches over time, so clean it regularly. Steel typically adds ₹2,000 to ₹5,000.

What tank size you need

6 to 7 litres is fine for a family of 2 to 3. 8 litres is the usual choice for 3 to 4 people. 10 to 12 litres suits a family of five or more, or heavy use. 15 litres suits a joint family or small office. A bigger tank also keeps water flowing in a power cut.

TDS controller: do you need one

RO takes out useful minerals along with the unwanted ones. A TDS controller mixes a little filtered bypass water back in. Manual ones have a screw you turn, and automatic ones use a sensor. Aim for output of about 50 to 150 ppm, and check with your meter after adjusting. Very low readings, say under 30 ppm, taste flat. If your purifier has no controller, an aftermarket one costs about ₹50 to ₹200 and a local technician fits it in minutes.

Alkaline, mineral and copper: what is worth it

In most purifiers the “mineral” and “alkaline” stages are the same cartridge: mineral balls that add calcium and magnesium and nudge the pH up, in one step. Brands list them as two features to pad the spec sheet. That one stage is the only one I would call needed after RO. Copper is a mild extra with known antimicrobial properties, but the amount a cartridge adds is small. Zinc and B12 claims are mostly marketing. An aftermarket 3-in-1 combo cartridge costs about ₹200 to ₹500, against ₹800 to ₹2,000 for branded ones.

Step 7

Water wasted and power used by an RO

Power is not the problem. Most RO purifiers draw 25 to 60 watts and run only while filling the tank, which comes to roughly ₹30 to ₹80 a month. Water is the real cost. Older RO designs reject two to three litres for every litre they purify. A family drinking 15 litres a day could send 30 to 45 litres down the drain.

Features that matter, and features that do not

Feature	Worth paying for?	Why
Long, unconditional warranty	Yes	Covers filters, membrane and electricals, so no surprise bills.
Open design, standard filters	Yes	Cheap parts and any technician can fix it.
Mineral or alkaline stage	Yes	Fixes flat taste after RO.
TDS control or adaptive mode	Yes	Keeps useful minerals and saves water.
Steel tank	Nice to have	Fresher in hot weather. Costs more.
App and filter alerts	Nice to have	Useful if you travel or want early warnings.
Copper infusion	Mild extra	Small amounts. Do not pay a big premium.
Zinc, B12 and vitamin claims	No	Mostly marketing.
Six or seven “stages” in the name	No	Count what each stage does, not the number.

Water purifier brands in India: ranked by what they cost to maintain

Most people compare price, tank size and the number of stages. Almost nobody compares what the purifier costs after the free service ends, and that is the number you pay for the next eight or ten years. So I ranked the brands by maintenance burden first, and service reach second. This is my own view, built from the plans, warranties and designs above. It is not a paid list.

How long is service free? Three years of free service is worth ₹9,000 to ₹15,000 compared with a brand that charges from year two.

What does the plan cost after that? A yearly plan of ₹4,000 to ₹5,000 adds ₹20,000 to ₹25,000 over five years. That can be more than the purifier.

Can you service it yourself? Standard cartridges and an open design let a local technician or you do the job for the price of the parts.

What do the parts cost? Filters are cheap. The membrane and pump are where the bill jumps, so check if the plan covers them.

Rank	Brand	What maintenance looks like	Honest downside
1	Urban Company Native	Three years of service-free running on current models, an unconditional warranty and fixed renewal pricing.	Service is urban-focused, so check your pin code.
2	Atomberg	No AMC for the first 2 years, then you pay mostly for parts that actually wear out.	Newer in purifiers, service still growing in small towns.
3	KENT	Simple designs and standard cartridges. Many people service it through a local technician and skip the plan.	The brand AMC is on the higher side, around ₹3,500 to ₹5,000 a year.
4	Aquaguard (Eureka Forbes)	Filter prices are fair and some models carry long warranties. Widest and oldest network.	AMC comes in several tiers and the cheap one covers little.
5	Havells	Decent build and an electricals-brand service network.	Warranty can be short and filters are not always covered.
6	Livpure	AMC is among the lowest of the big names, with copper and alkaline features.	Service speed varies by city.
7	Pureit (HUL)	Affordable to buy and available everywhere.	AMC and service run about ₹4,000 to ₹5,000 a year, and some models skip a TDS controller.
8	AO Smith and Blue Star	Strong engineering and build quality.	Higher AMC or a smaller service reach.

Rankings and amounts are indicative. AMC prices change by city, model and plan type, so always get the quote in writing before you buy.

Why Urban Company Native and Atomberg rank first

They take the maintenance question off the table for the first few years. Urban Company says its current Native models run three years without a service visit, backed by an unconditional three-year warranty. Atomberg gives you no AMC for two years. In both cases you buy once and the bill you were expecting in year one simply does not arrive. The trade-off is reach. Both are strongest in cities, so type your pin code on the brand site before you decide.

Why KENT is third, and what “service it yourself” means

KENT is not the cheapest brand to maintain if you buy its yearly plan. It ranks third because the design is simple and the cartridges are standard, so a local technician can change them, and a careful owner can do the basic filter swap too. You still need to know your water, but you are not locked into a ₹4,000 to ₹5,000 plan. If you want zero effort and no technician, the first two brands suit you better.

Aquaguard: fair filter prices, confusing plans

Aquaguard’s filter cost is fair, and some models carry a long warranty. The weak spot is the AMC menu. The entry plan costs a few hundred rupees and covers very little, while the higher tiers that include parts run into thousands. Ask which tier covers the membrane and the pump, then compare the total against buying the filters yourself.

Pureit and the rest: where the yearly bill adds up

Pureit and KENT both land around ₹4,000 to ₹5,000 a year when you take the full plan, but Pureit is harder to service independently and some of its models skip a TDS controller. Over five years that is roughly ₹20,000 to ₹25,000 on a machine that cost less than that to buy. Livpure and Havells sit in the middle, and AO Smith and Blue Star charge more for premium build.

One more thing before you read the picks. There are three kinds of AMC, and brands rarely explain the difference on the brochure.

Plan type	What you get	What you still pay for
Labour only	A technician visits and fits the parts.	Every cartridge, membrane and pump.
Parts only	Listed filters and parts are replaced.	Visits and any part not on the list.
Comprehensive	Visits plus parts, usually including the membrane.	Almost nothing, but it costs the most and has exclusions.

Five questions to ask the seller: Which plan type is this? Are the membrane and pump covered? How many visits a year? What does the plan cost in year three and year five? Can I get all of this in writing?

Our picks

Top 8 water purifiers in India right now

These are the eight picks from our full best water purifier in India ranking. Each one scores well on the things in this guide: service cost, warranty and water handling. The Urban Company Native M3 Pro comes first, and the Atomberg Intellon second.

Pick	Purifier	Best for
Best Overall	Urban Company Native M3 Pro	People who never want to think about service
Best Smart Pick	Atomberg Intellon	Mixed or changing water quality
Best for Big Families and DIY Repair	KENT Grand Star	Big families, Kent loyalists
Best Warranty	Aquaguard Aspire Glow	Longest cover and a huge service network
Best Value Urban Company	Urban Company Native M1	The Native idea for less
Best Steel Tank Value	Aquaguard Delight Aquasaver	A steel tank on a mid budget
Best Copper Pick	Havells Aquas Pro	Copper and zinc enrichment, free service
Best Budget Pick	Pureit Wave Pro	Tight budgets, a big brand behind it

Prices in the buy boxes are live. Warranty and service terms are the makers’ own. Read the full reviews and scores in our ranking.

Pick by water type and budget

You hate service calls: Urban Company Native M3 Pro.

Your water quality changes or is low in TDS: Atomberg Intellon.

Big family, lots of guests: KENT Grand Star for the 9-litre tank.

You want the longest warranty: Aquaguard Aspire Glow.

Native on a smaller budget: Urban Company Native M1.

Mid budget with a steel tank: Aquaguard Delight Aquasaver.

Mid budget with free service: Havells Aquas Pro.

Tight budget: Pureit Wave Pro, and plan for AMC after year one.

Before you buy

Final water purifier buying checklist

Check	Why it matters
Water TDS and source	Decides RO versus UV + UF. Measure it, do not guess.
Lab test if borewell	TDS cannot see lead, arsenic or fluoride.
Open, standard design	Cheap parts and any technician can service it.
Filter life in litres	More litres means fewer replacements.
5-year cost	Ask for the number. Price alone misleads.
What the warranty excludes	Membrane and pump are often left out.
TDS control or adaptive mode	Keeps minerals and cuts waste.
Tank material and size	Steel is fresher. 8 litres fits most families.
Pre-filter for borewell	A ₹300 to ₹500 part that extends filter life.
Service in your pin code	A great purifier is useless without nearby service.

Five mistakes to avoid

Buying on brand and price alone. The cost shows up in years two to five.

Skipping the TDS test. You may pay for RO you do not need, or skip RO you do.

Believing “low TDS means safe”. A meter cannot see heavy metals.

Falling for stage and cartridge counts. Alkaline and mineral are usually one cartridge.

Signing an AMC without reading it. Check whether the membrane and pump are included.

The bottom line

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Water purifier buying guide FAQ

Do I need RO in India?

In most Indian homes, it is the safe default. A TDS meter cannot see fluoride, arsenic, nitrate, uranium or germs, and government tests keep finding them. If a lab report shows your water is clean and low in TDS, UV plus UF can be enough. If you do not know what is in your water, choose RO plus UV with TDS control.

Can a TDS meter tell me if my water is safe?

No. A TDS meter counts everything dissolved in water but cannot tell harmless minerals from fluoride, nitrate or arsenic, and it cannot detect bacteria. It is useful to pick the right technology and to check your purifier output. Only a lab test tells you what is actually in the water.

Which is the best water purifier for Indian homes in 2026?

It depends on your water, so test TDS first. For most families who hate service calls, the Urban Company Native M3 Pro is the one I rate highest. For changing or low TDS water, the Atomberg Intellon is the smarter fit. For a big family, the KENT Grand Star has the biggest tank. Our full ranking has all eight picks.

How do I choose a water purifier in India?

Follow four steps. Measure your water TDS with a cheap meter. Pick the technology that matches it (RO for high TDS, UV or UF for clean low TDS water). Check the 5-year cost including service, not just the price. Then check that the design is simple enough to repair and that the brand services your pin code.

Do I need RO if my TDS is below 200?

Not always. If you get clean municipal water with low TDS, UV plus UF can be enough. But a TDS meter cannot see lead, arsenic, fluoride or nitrate. If you use borewell water or live where those are known problems, get a basic lab test before you decide.

What TDS level is safe for drinking water in India?

The BIS standard IS 10500 gives 500 mg/L (ppm) as the acceptable limit, and allows up to 2,000 mg/L only where no better source exists. It sets no minimum TDS. WHO has no health-based TDS limit either, and calls water below 300 mg/L excellent for taste.

Is RO water harmful because it removes minerals?

The honest answer is that experts disagree and more study is needed. Most of your minerals come from food. But very low TDS water tastes flat, and in 2019 the National Green Tribunal asked for RO to be avoided where TDS is under 500 mg/L. A sensible middle path: use RO only where you need it, and keep the output around 50 to 150 ppm with a TDS controller or mineral cartridge.

RO, UV or UF: which one is better?

None is better in every case. RO removes dissolved salts, heavy metals and fluoride. UV kills germs but removes nothing. UF filters out bacteria and fine particles but not dissolved salts. Most Indian purifiers combine them so one covers the gaps of the other.

How much does water purifier service cost in India?

Typical yearly AMC plans run from about ₹2,000 to ₹6,000 depending on the brand and what the plan includes. Many plans leave out the RO membrane and pump. A local technician with aftermarket parts is usually cheaper, if your purifier is easy to open.

Can I change water purifier filters myself?

Yes, if the purifier has push-fit connectors and standard-size filters. Inline filters take about five minutes with no tools. Ask the seller to show you the filter change before you buy. If it needs a technician and special tools, the internals are probably cramped or proprietary.

How often should I change RO filters and the membrane?

Check filter life in litres, not months. Sediment filters often last around 4,000 to 6,000 litres, and an RO membrane around 6,000 to 12,000 litres. Heavy borewell water shortens that, and a pre-filter can extend it.

Is a steel tank better than a plastic tank?

Stainless steel (304 grade) is more durable and stays fresher in hot weather. Food-grade ABS plastic is safe and cheaper if you clean it regularly. Steel typically adds ₹2,000 to ₹5,000 to the price.

What size water tank do I need?

Six to seven litres suits a family of two or three. Eight litres is the standard for three or four people. Ten to twelve litres suits five or more, or heavy use. Bigger tanks help during power cuts.

How much water does an RO purifier waste?

Older RO purifiers commonly reject two to three litres for every litre they purify. Newer designs claim big savings through recirculation, higher recovery or adaptive modes. Whatever the model, collect the reject water for mopping, plants and flushing.

Do RO purifiers use a lot of electricity?

No. Most draw 25 to 60 watts and run only while filling the tank. That works out to roughly ₹30 to ₹80 a month. Water and service costs matter far more than power.

What is a TDS controller and do I need one?

It is a valve that mixes a little filtered bypass water with the RO water so some minerals stay. Manual ones you adjust with a screw, automatic ones use a sensor. If your purifier lacks one, an aftermarket part costs about ₹50 to ₹200.

Are alkaline, mineral and copper cartridges worth paying for?

A mineral or alkaline stage is the one worth having after RO, because it fixes flat taste. In most purifiers the two are the same cartridge sold under two names. Copper is a mild extra. Do not pay a big premium for a long list of buzzwords.

Which water purifier has the lowest maintenance cost?

Among the picks in our ranking, the Urban Company Native M3 Pro offers three years with no service, the Native M1 and Atomberg Intellon two years, and the Aquaguard Aspire Glow four years of cover. A purifier with open internals that you can self-service is also cheap to run.