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Waterdrop’s summer sale cuts up to $700 off its high-end home water filters

The company dropped prices across the board on its installed and counter top water filters for cleaner water in your home.

By Stan Horaczek

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A good reverse osmosis system is one of those home upgrades that’s easy to keep putting off, mostly because the ones worth owning run a few hundred dollars. Waterdrop timed its Waterdrop Day Sale to run alongside Prime Day, June 23 through 26, and it’s taking up to $700 off under-sink RO systems, countertop filters, whole-house setups, and hot-water dispensers. Waterdrop is also backing the sale with 30-day price protection, so if a price drops again before the event closes, you can ask for the difference. The five we’d buy first are in the cards below, and the rest are grouped by what they actually do, so you can jump to the type that fits your kitchen. Prices can move during a sale like this, so confirm the current number before you check out.

Waterdrop G3P600 Reverse Osmosis System $399.00 (was $539.00)

The tankless under-sink system most kitchens should start with, 26% off

Waterdrop G3P600 Reverse Osmosis System
Never drink gross water again.

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The G3P600 is the one most people should look at first at $399, 26% off its $539 list price. It’s a tankless under-sink system, so it mounts to your cold-water line and sends filtered water straight to a dedicated faucet without a bulky storage tank eating up cabinet space. Reverse osmosis is the most thorough filtration you can put under a sink, cutting dissolved solids, lead, and a long list of other contaminants, and Waterdrop lists NSF/ANSI certifications for this one. For a typical household that just wants better drinking and cooking water, this is the sensible middle of the lineup. I reviewed the G3P800 a while back and was very impressed with its performance.

Waterdrop M6SL Countertop Reverse Osmosis System $229.00 (was $329.00)

No-install RO for renters who can’t drill into the plumbing, 30% off

Waterdrop M6SL Countertop Reverse Osmosis System
The countertop solution eschews installation.

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If you rent or just don’t want to touch your plumbing, the M6SL gives you the same reverse osmosis filtration in a countertop box at $229, 30% off. It sits on the counter and pours remineralized water on demand, so there’s no faucet to install and nothing to drill. This is the pick for apartments, offices, or anyone who wants RO water without a contractor, and at this price it’s an easy first step up from a pitcher.

Waterdrop WHF21-PG 2-Stage Whole House Water Filter $109.99 (was $165.99)

Whole-home sediment and carbon filtration for the price of a few pitcher refills, 34% off

Waterdrop WHF21-PG 2-Stage Whole House Water Filter

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For water that’s better everywhere in the house, not just at one faucet, the WHF21-PG is the cheapest way in at $109.99, 34% off. It’s a two-stage system that installs on your main line to handle sediment and chlorine taste and odor before water reaches your taps, showers, and appliances. It won’t do what a reverse osmosis system does at the kitchen sink, but it handles the foundational filtration that protects your plumbing and makes every tap in the house taste better, and it’s cheap enough to pair with one of the RO picks above.

Waterdrop X16 Undersink Reverse Osmosis System $1,299.00 (was $1,999.00)

The $700-off headline deal, sized for big or hard-water households

Waterdrop X16 Undersink Reverse Osmosis System
This is a serious system for long term use.

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The X16 is the one carrying that “up to $700 off” banner, down to $1,299 from $1,999. It’s the top of Waterdrop’s under-sink RO line, a tankless system built for high output, which matters if you have a big family hitting the faucet all day or you’re filtering particularly bad tap water. This is a real investment even on sale, so it’s overkill for a one- or two-person apartment, but the dollar discount is the largest in the event and it’s the system to look at if you’ve decided you want Waterdrop’s best.

Waterdrop K6 Instant Hot Water Reverse Osmosis Dispenser $499.00 (was $799.00)

RO filtration plus on-demand hot water, 38% off

Waterdrop K6 Instant Hot Water Reverse Osmosis Dispenser
The clean water will make your coffee maker and other appliances last longer, too.

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The K6 carries one of the steepest percentage cuts in the sale, $499 from $799, a 38% drop. It pairs reverse osmosis filtration with an instant hot-water tap, so you get near-boiling water for tea, coffee, and instant noodles without waiting on a kettle. If you’ve ever wanted a hot-water dispenser and a filtration upgrade in one fixture, this is the deal that makes the splurge easier to stomach.

Best Waterdrop under-sink reverse osmosis system deals

These are the tank-free systems that mount under your sink and run to a dedicated faucet, the core of Waterdrop’s lineup. The G3P600 at $399 (26% off) is the one most kitchens should land on, while the X16 and X12 models step up output and capacity for bigger households. Several of these also come in alkaline or remineralizing versions that add minerals back after filtering.

Best Waterdrop countertop and instant-hot RO deals

No drilling, no plumber, no permanent install. These countertop systems give you reverse osmosis water from a unit that sits next to the sink, and several add an instant hot-water function for tea and coffee. The M6SL at $229 (30% off) is the easiest one to recommend for renters, and the instant-hot K19 and M1 models are worth the step up if you want near-boiling water on demand.

Best Waterdrop hot and cold water dispenser deals

These combine reverse osmosis filtration with a built-in dispenser that pours hot, cold, or room-temperature water, so they can replace both a filter and a water-cooler jug. The K6 at $499 (38% off) is the standout discount, and the A-series dispensers add remineralization if you prefer water with minerals left in.

Best Waterdrop whole-house water filter deals

Whole-house systems install on your main water line and treat everything before it reaches your taps, showers, and appliances, which is the move if you’re dealing with sediment, chlorine, or well-water iron and manganese. The WHF21-PG at $109.99 (34% off) is the cheapest entry, and the three-stage FG models are built specifically to knock down iron and manganese staining.

Best Waterdrop under-sink and ultrafiltration filter deals

If you don’t need full reverse osmosis, these simpler under-sink and ultrafiltration systems are a cheaper way to improve taste and cut contaminants, and most install in well under an hour. The TST-UF at $141.99 (25% off) is a stainless-steel six-stage system, while the 10UA at $56.99 is the budget pick that connects directly to your existing cold line.

Best Waterdrop gravity and specialty filter deals

These need no plumbing at all. The King Tank gravity systems filter water through a countertop tank you fill by hand, which makes them useful for camping, emergencies, or a kitchen where installing anything is off the table, and the ED01 is a plug-in electric filter that’s barely more than a nice pitcher.

Waterdrop’s prices can shift during the sale, so confirm the current number before you check out, and remember the 30-day price protection if it drops further. If you only buy one thing and you can install under your sink, make it the G3P600 at $399. If you can’t drill, the M6SL countertop system gets you the same kind of water for $229.

 
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Stan Horaczek

Executive editor, gear and reviews

Stan Horaczek is the executive gear editor at Popular Science. He oversees a team of gear-obsessed writers and editors dedicated to finding and featuring the newest, best, and most innovative gadgets on the market and beyond.