Water 101 · 9 min read
Chlorine vs. Chloramine: What's in Your Water and How to Remove It
By Jason Preston, Founder · June 2026
Chlorine and chloramine are both used to disinfect municipal water — but they behave very differently once they reach your tap. Chlorine is relatively straightforward to filter out with quality carbon media. Chloramine is far more stable and requires catalytic carbon to break its chemical bond. The question I get asked most is: "Why does my water still smell chemical after I installed a filter?" In most of those cases, the homeowner is on chloramine and has a filter designed for chlorine.[1]
When people ask me what's in their tap water, the first thing I check is whether their utility uses chlorine or chloramine for disinfection. It matters more than most people realize — not because either one is alarming at the concentrations used for treatment, but because they have meaningfully different effects on taste, skin, and filter performance. Getting this wrong leads to a lot of wasted money on the wrong filtration media.
What Are Chlorine and Chloramine?
Chlorine has been the workhorse of municipal water disinfection for over a century. It's a highly effective disinfectant — it kills bacteria, viruses, and other pathogens rapidly, and it's been a cornerstone of public health infrastructure in the United States since the early 1900s.[2] The "pool water" taste and smell that many people associate with tap water is free chlorine.
Chloramine is a compound formed by combining chlorine with a small amount of ammonia. It's a secondary disinfectant — meaning it's less powerful than free chlorine at killing pathogens outright, but it's far more stable. Chloramine persists in the water distribution system longer, which makes it useful for treating large systems where water travels long distances from treatment plant to tap.
The most common form used in water treatment is monochloramine (one chlorine atom bound to one ammonia molecule). When I use the word "chloramine" in this article, that's what I mean.
Why Cities Use One vs. the Other
The primary driver behind a utility's choice isn't customer preference — it's disinfection byproducts. When chlorine reacts with naturally occurring organic matter in water (leaves, soil, decaying vegetation), it can form a class of compounds called trihalomethanes (THMs) and haloacetic acids (HAAs), which the EPA regulates as potential health concerns with long-term exposure.[3]
Chloramine produces fewer of those regulated byproducts. For larger cities with long distribution systems, that's a meaningful compliance advantage. The EPA and CDC both recognize chloramine as a safe, legal disinfectant when used within established limits.[4]
The tradeoff — and this is where homeowners need to pay attention — is that chloramine creates its own set of byproducts when it reacts with organic matter, including iodoacids and N-nitrosodimethylamine (NDMA), which continue to be studied. The research is ongoing; my point isn't to alarm anyone, but to note that "fewer regulated byproducts" doesn't mean "no byproducts."
In practice: smaller utilities and those with shorter distribution systems tend to stick with chlorine. Larger cities — Denver, Phoenix, Houston, Portland, and many others — have shifted to chloramine. If you've recently moved from a small town to a metro area and noticed a change in your water's character, this is often why.
Taste, Smell, Skin, and Health Effects
Both disinfectants are added at very low concentrations — typically 1–4 mg/L for chlorine, similar for chloramine. The EPA sets a maximum residual disinfectant level (MRDL) of 4 mg/L for both. Most people aren't at risk from the disinfectant itself at those levels. But the effects on daily life are real.
Taste and Smell
Chlorine's signature is that sharp, chemical, pool-like smell. It's distinctive and most people recognize it. The good news: it's volatile, so it dissipates relatively quickly once water is drawn and left to sit.
Chloramine smells different — more medicinal or earthy, sometimes described as a "wet dog" or slightly bitter chemical note. It does not dissipate by letting water sit out, because its bond is stable. That's the first thing that trips people up when they move to a city that uses it.
Skin and Hair
Both chemicals can strip natural skin oils, leading to dryness and irritation — particularly noticeable in a hot shower, where steam and absorbed water both carry the disinfectant. In my experience talking with customers, people with sensitive skin, eczema, or young children at home notice this the most. Chloramine is particularly associated with skin and eye irritation in some sensitive individuals, possibly because it's harder to outgas and remains active in shower steam longer than free chlorine.
Health Considerations Worth Knowing
For most healthy adults, the disinfectants used in public water at regulated concentrations are not a significant health concern. There are two groups who need to be more careful:
- Dialysis patients: Chloramine can pass through dialysis membranes and enter the bloodstream directly. Dialysis centers treat all incoming water to remove chloramine — but if you're doing home dialysis, this is critical to discuss with your care team.[5]
- Fish and reptile owners: Chloramine is toxic to aquatic life. Dechlorination tablets designed for fish tanks often don't neutralize chloramine — you need a product specifically labeled for it, or filtered water.
For most households, the motivation to filter isn't fear — it's taste, smell, and skin comfort. Those are legitimate reasons and worth addressing.
Why Chloramine Is Harder to Remove
This is the part that catches most people off guard. Standard activated carbon — the media in most pitcher filters, refrigerator filters, and basic faucet filters — is quite effective at adsorbing free chlorine. But chloramine's chemical bond is significantly more stable. Standard carbon can reduce chloramine, but it does so slowly and incompletely, requiring much longer contact time than typical filters allow.[1]
Catalytic carbon is a different animal. Through a modified manufacturing process, catalytic carbon gains the ability to chemically catalyze reactions — actively breaking down contaminants rather than just trapping them on its surface. For chloramine specifically, catalytic carbon breaks the chloramine bond, converting it into harmless components (chloride and ammonia nitrogen, which are then further processed or safely dispersed). This is a fundamentally different mechanism, not just a faster version of standard adsorption.
The ToxyGuard media at the core of the Sentry H2O systems we carry is a catalytic carbon blend, formulated specifically for this job. It handles chlorine and chloramine, but also addresses VOCs, fluoride, lead, and arsenic — contaminants that often travel together in water with disinfection concerns. (PFAS is measured for the full system in independent lab testing.) That breadth is one reason I chose to build around it.
The practical takeaway: if your city uses chloramine and you install a filter with standard activated carbon, you may get partial improvement in taste but not the full removal you're expecting. The media matters, and it's worth checking what's inside the filter before you buy.
How to Find Out Which Your Utility Uses
The easiest route is your utility's Consumer Confidence Report (CCR) — also called an annual water quality report. Public water systems in the U.S. are required by the EPA to deliver this report to customers every year.[6] It lists all detected contaminants, the disinfection method used, and levels compared to regulatory limits.
To find yours: search your water utility's name plus "water quality report" or "CCR." Most utilities post them on their websites and some mail them. If you can't find it online, call your utility's customer service line and ask directly: "Do you use chlorine or chloramine for disinfection?" They'll know immediately.
A few things to look for in your CCR once you have it:
- The disinfectant type (chlorine, chloramine, or both at different stages)
- The measured residual level at various points in the distribution system
- Any detected disinfection byproducts (THMs, HAAs) and their levels vs. limits
Once you know what you're dealing with, you can choose a filter that's actually matched to your water.
Solutions: Drinking, Bathing, and Whole House
The right answer depends on what you're trying to protect — your drinking water, your skin in the shower, or every tap in your home. In most cases I walk people through a tiered approach: start where the impact is highest, add coverage as it makes sense for your situation.
For Drinking and Cooking: Under-Sink Filtration
The 5-stage Sentry H2O Wellness System is our under-sink drinking solution and what I recommend as the starting point for most households. It installs under your kitchen sink in about 30 minutes — no plumber needed, fittings and a tube cutter included — and gives you a dedicated filtered-water tap.
The ToxyGuard catalytic-carbon stage handles both chlorine and chloramine (along with VOCs, fluoride, lead, and arsenic). The BioChemGuard stage in the TriGuard configuration adds a submicron barrier against bacteria, viruses and cysts. And the AlkaGuard stage re-mineralizes the water — adding back calcium and magnesium and raising pH to roughly 8–9.5 — so you're left with something that tastes genuinely good, not flat or stripped. Filters are replaced about once a year.
This is the solution for the water you drink and cook with. It doesn't cover your shower or other taps — that's what the next two options address.
For Bathing: The Shower Filter
Hot showers are where chloramine's skin and respiratory effects are most noticeable. Steam from chloraminated water carries residual disinfectant into the air you breathe; the hot water opens pores and increases skin absorption. A quality shower filter makes a visible difference — many customers tell me their skin feels noticeably different within a week.
The Sentry H2O Shower Filter is designed specifically for chloramine removal using catalytic carbon media — not the basic KDF or vitamin C media found in many shower filters, which target free chlorine but are far less effective on chloramine. Installation takes minutes and requires no tools. The cartridge lasts approximately 3,000 gallons — roughly one year at one shower per day, or about six months at two or more daily showers.
For Every Tap: Whole-House Coverage
If you want chloramine removed at every faucet, appliance, and showerhead in your home, a whole-house system is the answer. The Sentry H2O Whole House Wellness System uses a ToxyGuard Pro catalytic-carbon tank to treat all water entering your home, paired with salt-free scale-control media to prevent mineral buildup without brine discharge. An optional VIQUA VH200 UV system can be added for microorganism coverage (cryptosporidium, giardia, E. coli) if your source has biological concerns.
Whole-house systems require professional installation — this isn't a weekend DIY project. For city water, the tank media is refreshed via a Whole Home Revitalizer on a schedule that depends on household size: every three years for a single person, every two years for two to three people, every year for four or more. Includes an under-sink drinking system.
For households with chloramine concerns throughout the home — not just at the kitchen tap — this is the most complete solution. For most people starting out, I still recommend beginning with the under-sink system and shower filter, seeing the difference, then deciding if whole-house coverage makes sense for your situation. Our whole-home vs. under-sink guide walks through that decision in detail.
Not sure what's right for your home?
Take the 60-second quiz — I'll walk you through it based on your water source, household size, and what's bothering you most.
Take the quizFrequently Asked Questions
Does standard activated carbon remove chloramine?
Not reliably. Standard activated carbon is effective against free chlorine but struggles with chloramine because chloramine's chemical bond is far more stable. Catalytic carbon — a more advanced form — is specifically engineered to break that bond, and is the media you want for chloramine removal. Most basic pitcher and faucet filters use standard carbon; check the spec sheet before assuming yours handles chloramine.
How do I find out if my city uses chlorine or chloramine?
Your utility's annual Consumer Confidence Report (CCR) will list which disinfectant is in use. Search your utility's name plus "water quality report" or "CCR" — or call them directly and ask. The EPA requires public water systems to publish this report every year.[6]
Does a shower filter help with chloramine?
It depends on the filter media. Many basic shower filters target only free chlorine via KDF or vitamin C media. If your city uses chloramine, look specifically for a shower filter that uses catalytic carbon or states chloramine removal on its spec sheet. The Sentry H2O Shower Filter is built for this.
Will boiling water remove chlorine or chloramine?
Boiling will dissipate free chlorine relatively quickly, but it is much less effective against chloramine and impractical for daily household use. For consistent removal at the tap, filtration is the right tool.
Is chloramine in drinking water dangerous?
At the levels used for disinfection, chloramine is considered safe for most people under EPA standards. Dialysis patients are the key exception — chloramine passes through dialysis membranes and must be removed at dialysis centers and in home dialysis setups.[5] For most households, the motivation to filter is taste, smell, and skin comfort — all legitimate and addressable.
Sources
[1] NSF International — NSF/ANSI 42 Standard for Drinking Water Treatment Units — Aesthetic Effects. Covers reduction of chlorine taste and odor; catalytic carbon systems tested under this standard demonstrate significantly higher chloramine reduction rates than standard activated carbon at equivalent contact times. Separate listing required for chloramine reduction claims.
[2] U.S. Centers for Disease Control and Prevention (CDC) — Water Disinfection with Chlorine and Chloramine. Overview of chlorination history, mechanism, and regulatory context in U.S. public water systems.
[3] U.S. EPA — Disinfection Byproducts (DBPs). Describes the formation of trihalomethanes and haloacetic acids from chlorine reacting with natural organic matter, and the regulations governing their levels in public water.
[4] U.S. EPA — Chloramine in Drinking Water. Official EPA Q&A on chloramine use, safety, and effects on sensitive populations. Sets maximum residual disinfectant level (MRDL) at 4 mg/L for chloramine.
[5] U.S. EPA — Chloramine in Drinking Water — Sensitive Populations. Notes that chloramine can pass through dialysis membranes; dialysis centers are required to treat water to remove chloramine before it is used in dialysis treatment.
[6] U.S. EPA — Consumer Confidence Reports (CCR). Public water systems must provide customers with an annual drinking water quality report. Reports include the disinfectant type and residual levels, detected contaminants, and comparisons to regulatory standards.
Keep reading
Educational guidance only — not health or medical advice. For health concerns related to water disinfectants or disinfection byproducts, consult your physician or local health department. Regulatory specifics should be verified against current primary sources before any decision.