Boiling does remove free chlorine, because chlorine is a dissolved gas that comes out of solution faster as the water heats. What boiling does not do is remove chloramine effectively, and what it actively does is concentrate every non volatile thing left in the pot as steam leaves. Whether boiling is a sensible answer depends on which disinfectant your utility uses.
Why free chlorine leaves and chloramine stays
Free chlorine is volatile and only loosely held in solution, so heat and agitation drive it off, which is why a covered jug in the refrigerator also works given time. Chloramine is chlorine bonded with ammonia, and it was adopted by many utilities precisely because it is far more stable and persists further into the distribution system. That stability is what defeats boiling. A brief boil barely touches chloramine, and a long boil is an expensive way to make a small difference.
Find out which one you have
This is not something you can taste reliably. Every community water system publishes an annual Consumer Confidence Report naming the disinfectant it uses, and the EPA maintains a finder for those reports. Look yours up before deciding what to do, because the answer changes the method completely: free chlorine responds to standing, chilling and carbon, while chloramine effectively requires catalytic carbon. Well owners have no disinfectant unless they added one themselves.
What boiling makes worse
Boiling reduces the volume of water while leaving behind everything that is not volatile. Nitrate, lead, arsenic, hardness minerals and dissolved solids all remain in the pot, so a hard boil leaves you with a slightly more concentrated version of those. This is the point people miss when boiling is recommended as a general purification measure. Boiling is a treatment for microorganisms during a boil notice, and it is not a treatment for chemistry.
The methods that actually remove chlorine
Activated carbon adsorbs free chlorine efficiently in a pitcher, faucet mount, countertop or under sink cartridge. Catalytic carbon, a treated form with more active surface chemistry, is the standard answer for chloramine and is what whole house systems in chloraminated areas are built around. Reverse osmosis systems remove it too, mainly through the carbon stages ahead of the membrane, which also exist to keep chlorine from attacking the membrane itself. Our water filtration system cost guide covers what those options run.
When boiling is exactly the right thing
If your utility issues a boil water notice, or a well test comes back positive for coliform bacteria, boiling is the correct emergency response and chlorine is not the point. Bringing water to a rolling boil deals with bacteria, viruses and protozoa, which is precisely what those notices are about. Use boiling for the microbiological problem it solves, and use carbon for the chlorine taste problem it solves. Confusing the two is how people end up boiling water for months for no reason.
Questions people ask about does boiling water remove chlorine
How long do I need to boil water to remove chlorine?
There is no useful published interval, and the honest answer is that letting water stand covered in the refrigerator achieves much the same for free chlorine with no energy cost at all.
Does boiling remove chloramine?
Barely. Chloramine is deliberately stable and resists heat far better than free chlorine does. Catalytic carbon filtration is the practical household answer where the utility uses chloramine.
Does boiling remove lead?
No, and it makes it slightly worse. Lead is not volatile, so it stays in the pot while steam leaves, which concentrates it. Lead needs a certified filter or reverse osmosis.
Is chlorinated tap water safe to drink anyway?
Disinfection is why municipal water is microbiologically safe, and most people who filter it are removing a taste rather than a hazard. Your utility report tells you what levels they are treating to.