Chlorine is added to municipal water supplies intentionally. It kills bacteria, viruses, and other pathogens during the treatment process and continues protecting water as it travels through miles of pipes to your home. The problem is that by the time it arrives at your tap, that chlorine — and its byproduct chloramines — affects taste, smell, and potentially your skin and hair. The good news is that removing it is straightforward.
Why Does Chlorine End Up in Your Drinking Water?
The EPA requires public water systems to maintain a minimum chlorine residual of 0.2 milligrams per liter at the tap to ensure water stays disinfected throughout the distribution system. Most utilities add enough chlorine at the plant to maintain this level even at the farthest points in the system, which means water near the plant often has higher levels — sometimes 1 to 4 mg/L — that are detectable by smell and taste.
Chloramines are a variant used by some utilities. Formed by combining chlorine with ammonia, they last longer in the distribution system but are harder to remove than free chlorine.
Method 1: Activated Carbon Filtration (Best Option)
Activated carbon is the most effective and practical way to remove chlorine from tap water. Carbon has an enormous surface area — one gram contains roughly 32,000 square feet of surface — that attracts and traps chlorine molecules through a process called adsorption.
Carbon filter options:
- Pitcher filters (Brita, PUR, ZeroWater): Use granular activated carbon or carbon block. Effective and inexpensive, but require frequent cartridge changes and only filter small volumes at a time.
- Faucet-mounted filters: Attach directly to your tap. Convenient for single-point use. Filter life is typically 100 gallons.
- Under-sink carbon filters: Higher capacity and better filtration than pitcher filters. Filter 500 to 1,000 gallons before cartridge replacement.
- Whole house carbon filters: Install on the main supply line and remove chlorine from every tap, including showers. The best option for whole-home protection.
For chloramines (check your CCR to see if your utility uses them), choose a filter with catalytic carbon, which is specifically designed to break down chloramines. Standard activated carbon is much less effective against chloramines.
Method 2: Reverse Osmosis
Reverse osmosis systems include a carbon pre-filter stage that removes chlorine before the water reaches the semi-permeable RO membrane (chlorine would degrade the membrane quickly without this protection). If you already have or are considering an RO system for your kitchen tap, chlorine removal is included automatically.
Method 3: Letting Water Stand (Limited Effectiveness)
Free chlorine naturally off-gasses over time. Leaving a pitcher of tap water uncovered at room temperature for 30 minutes to an hour will reduce free chlorine levels noticeably, and leaving it for several hours can eliminate most of it. This works for free chlorine only — chloramines do not evaporate at any practical rate.
This method is free and requires no equipment, but it is slow, only works for free chlorine, and is impractical for any significant water volume.
Method 4: Boiling
Boiling water for one minute will drive off free chlorine through evaporation. Like letting water stand, boiling does not effectively remove chloramines. It is also energy-intensive and impractical as a daily solution for drinking water.
Method 5: Vitamin C (Ascorbic Acid)
Adding vitamin C to water neutralizes both free chlorine and chloramines quickly. This method is popular among aquarium owners who need to dechlorinate water immediately. One gram of vitamin C neutralizes approximately 100 gallons of chlorinated water.
For drinking water, food-grade ascorbic acid powder is available cheaply online. However, adding vitamin C changes the water’s chemistry slightly and some people notice a mild taste at higher concentrations. It is more practical for occasional use than as a daily solution.
What About Chlorine in Shower Water?
Chlorine in shower water can dry out skin and hair, and some research suggests that inhaling chlorine vapors during a hot shower may be a concern with prolonged exposure. Options for shower chlorine removal include:
- Whole house carbon filter: Removes chlorine at the entry point, protecting every outlet including showers.
- Inline shower filter: Installs between the shower arm and head. Costs $20 to $60 and lasts 6 to 12 months. Effective for basic chlorine reduction.
Comparing Methods at a Glance
- Best overall: Whole house carbon filter or under-sink carbon filter
- Best budget option: Pitcher filter with activated carbon
- Best for chloramines: Catalytic carbon filter
- Best for showers: Whole house filter or inline shower filter
- No cost option: Letting water stand (free chlorine only)
Bottom Line
Activated carbon filtration is the most practical and cost-effective way to remove chlorine from tap water. For drinking water only, a pitcher filter or under-sink unit is sufficient. For whole-home protection including showers, a whole house carbon filter is the better investment. If your utility uses chloramines instead of free chlorine, verify that any filter you buy uses catalytic carbon.
Disclaimer: Chlorine levels in drinking water within EPA limits are considered safe for consumption. If you have specific health concerns, consult your physician.