Quick Answer: Get catalytic carbon, and get plenty of it. Our top pick is the Tier1 Whole House Chloramine System (450,000 gallon): an upflow tank preloaded with 1 cu ft of catalytic carbon, sold for chloramine, chlorine and hydrogen sulfide, that needs no electricity, drain or backwash. If you have the drain and outlet for a backwashing tank, the Fleck Centaur Catalytic Carbon Filter is the other strong choice. Prefer cartridges? Go with the radial-flow Home Master HMF2SmgRFCC.
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Most whole house filters marketed for "chlorine" will quietly underperform on chloramine. Chloramine (chlorine bound to ammonia) is more stable than free chlorine, and that's exactly why utilities switch to it: it lasts longer in the pipes. It's also why the cheap carbon that easily strips chlorine lets chloramine slip through.
Look at how manufacturers label their own products. Home Master, Pentek, PureWater and Enpress all sell separate "catalytic" or "chloramine" carbon products alongside their standard carbon. Every filter on this list either uses catalytic carbon or is explicitly marketed for chloramine. That's the first filter we applied, and it cut the field fast.
In this guide
Confirm you actually have chloramine
Don't guess. Your utility's annual report will say "chloramine" or "monochloramine" if that's what they use. Many utilities also post it on their website. You can test at the tap too. Our guide to testing for chlorine vs. chloramine explains how to tell them apart with free- and total-chlorine strips.
If it turns out you have plain chlorine, you're overspending here. A standard carbon whole house filter will do.
Pick your path in 30 seconds
- Own the home, have floor space near the main, no drain nearby → Tier1 Whole House Chloramine System.
- Own the home, have a floor drain and an outlet, want the media to stay loose and clean → Fleck Centaur catalytic backwashing tank.
- Want cartridges you can change yourself, and need high flow → Home Master HMF2SmgRFCC.
- Tight budget, smaller household → iSpring WGB32B-KS.
- Already have a 20" Big Blue housing on the wall → drop in a Pentek CRFC20-BB.
Ranked by how much chloramine they can realistically handle
1. Tier1 Whole House Chloramine System (450,000 gallon, upflow)
One cubic foot of surface-modified catalytic carbon, certified to NSF/ANSI 42 and 53, preloaded in a tank plumbed so water flows up through the bed. Tier1 rates it at 450,000 gallons and says it reduces chloramine, chlorine, hydrogen sulfide, VOCs and taste and odor compounds. The head is a simple in-and-out design with no moving parts, so there's no electricity, drain or regeneration. It carries a 10-year limited warranty when bought from an authorized Tier1 distributor.
That upflow design is the point. Upflow is the usual way non-backwashing carbon tanks are built, and because there's no control valve, you don't need a drain line or an outlet near the main. That makes it the easiest tank to fit into a basement that was never set up for water treatment.
Who it's for: a typical single-family home on chloramine where you want years between service, not months.
Where it falls short: 1 cu ft is a modest bed for chloramine in a big, busy house, so in a 3+ bathroom home test after install (see below) before you trust it. Tanks also need floor space, so measure before you order. And with no backwash, any sediment that gets in stays in. Put a sediment pre-filter in front of it if your city water ever runs cloudy after main breaks.
2. Fleck Centaur Catalytic Carbon Filter
Centaur is a well-known catalytic carbon. One water treatment retailer describes it as a liquid-phase catalytic activated coconut shell carbon. Here it sits in a tank run by a Fleck control head, and the listing says it removes chloramines, chlorine and hydrogen sulfide.
A Fleck-controlled media filter backwashes on a schedule, flushing trapped particles to drain and loosening the bed. Over a long service life, that helps keep flow up and contact even.
Who it's for: homeowners with a floor drain or laundry standpipe and an outlet near the main, and anyone whose water occasionally carries sediment.
Where it falls short: it needs a drain and power, and each backwash uses water. Backwashing tanks also need enough flow from your supply to lift the bed. City pressure is usually plenty, but check the listing's backwash requirement against your service line.
3. Home Master HMF2SmgRFCC
This is the cartridge system that takes chloramine seriously. Stage one is Home Master's 4-layer gradient sediment filter (25 down to 1 micron). Stage two is a radial-flow catalytic carbon cartridge rated at 20 gpm, with 1" NPT ports. The replacement cartridge is listed as granular catalytic carbon, radial flow, 20 gpm.
Radial flow keeps pressure loss low at high flow, which matters with chloramine, because the usual fix of "just add more carbon stages" also adds more pressure drop.
Who it's for: people who want a wall-mounted filter, no drain, no power, and a 20-inch cartridge they can change on a Saturday.
Be realistic about cartridge life. A single 20" cartridge holds far less carbon than a 1.5–2 cu ft tank. Chloramine eats into catalytic capacity faster than chlorine does, so expect more frequent changes than the same cartridge would need on chlorine. We couldn't find a published gallon rating for chloramine specifically. Track taste and smell, and test total chlorine after the filter every couple of months.
4. iSpring WGB32B-KS
Three 20-inch stages: sediment, then KDF, then carbon. iSpring's listing names chloramine, chlorine, hydrogen sulfide, heavy metals and sediment among what it reduces.
We include it because it's an affordable, widely available way to get more chloramine reduction than a basic carbon filter, using standard Big Blue parts. But be clear on what it is. Its listing doesn't say the carbon is catalytic, and we didn't find a chloramine performance figure.
Who it's for: smaller households, renters who can install and remove a wall-mounted filter, or anyone who mostly wants the bleachy smell gone from showers.
Who should skip it: anyone running a dialysis machine or an aquarium off household water, or anyone with a medical reason to care about residual chloramine. For those, use a large catalytic tank and confirm the result with a total-chlorine test.
5. Pentek CRFC20-BB
This isn't a system. It's a chloramine reduction carbon cartridge in the 4.5" × 20" Big Blue size, made by Pentair's Pentek line. Pentek rates it for chloramine reduction of 25,000 gallons at 2.5 gpm (and over 200,000 gallons for chlorine at 4 gpm), with a spun polypropylene wrap and post-filter to keep carbon fines out of your water, and says to replace it every year. If you already have a whole house housing on the wall with a regular carbon cartridge in it, this is the cheapest meaningful upgrade.
Who it's for: anyone with existing 20" Big Blue housings. Pair it with a sediment cartridge upstream so the block doesn't clog.
Downside: it's one cartridge, so contact time is limited. That 25,000-gallon chloramine rating is a fraction of the chlorine rating, and a family of four can use that in a few months. Treat it as an upgrade, not a replacement for a properly sized catalytic tank.
Why bed size matters more than brand
With chloramine, contact time does most of the work. The longer the water sits against catalytic carbon, the more of it gets broken down. You get more contact time in two ways: more media or slower flow.
That's why the ranking above roughly follows media volume. A cubic foot or more of carbon in a tank simply holds more than one 20-inch cartridge. If your house has three or more bathrooms and you often run two showers plus a dishwasher, lean toward the biggest tank that fits.
A quick sanity check after install: test total chlorine at a tap after the filter, with water running at what you consider a busy-morning flow. If it reads clean then, you're sized right.
If you have a softener, this matters even more
Chloramine is hard on softener resin. Our explainers on how chloramine affects a water softener and how chlorine damages softener resin go into the detail. In short, put the catalytic carbon filter upstream of the softener so the resin only ever sees dechlorinated water. If you're planning both, read running a carbon filter and water softener together before you lay out the plumbing.
Living with it: maintenance by type
How much work you're signing up for depends on the format.
- Upflow catalytic tank (Tier1): no routine work beyond the sediment pre-filter. When chlorine starts showing up on a total-chlorine strip after the tank, the media is spent. You rebed the tank, not replace the system.
- Backwashing tank (Fleck Centaur): check that the control's clock is right after power outages, and that the drain line isn't kinked. Otherwise, same as the upflow tank: test, and rebed when results slip.
- Cartridge systems (Home Master, iSpring, Pentek): change the sediment cartridge whenever the pressure gauges show a growing gap, and the carbon on a schedule you set from testing. On chloramine, start by testing monthly for the first few months so you learn how fast your cartridge actually runs out.
A tip that saves frustration: buy the total-chlorine test strips when you buy the filter. Without them you're guessing. A filter that's "still working" by smell may already be letting chloramine through.
Questions we hear about chloramine filters
Will a shower filter do instead? For one bathroom, it can help. But most shower filters are small, and chloramine is the hard case for small filters. A whole house system covers every tap, and the washer and water heater too.
Do I still need a sediment pre-filter on city water? For the tanks, it's cheap insurance, especially after main breaks or hydrant flushing stir things up. The two cartridge systems already include a sediment stage.
My utility switches between chlorine and chloramine during the year. Which filter? Buy for chloramine. A catalytic filter handles chlorine too, but a standard carbon filter won't handle chloramine well.
First-week notes
New carbon, catalytic or not, sheds fine black dust. Flush through a tub spout or outdoor spigot until the water runs clear. If you still see specks days later, see black carbon fines after a new filter. Then write the install date on the tank or housing with a marker. Six months from now you won't remember it.