How PUR Water Filters Work and What They Remove
What PUR filters actually do
PUR is a brand of pitcher and faucet-mounted water filters that use activated carbon and ion exchange to reduce certain contaminants. The filters don't remove everything from tap water — they target specific things like chlorine taste and odor, lead, mercury, and some pesticides. What passes through depends on which PUR model you own, because different filters have different capabilities.
PUR filters work by forcing water through layers of material. Activated carbon traps molecules that cause taste and smell problems. Ion exchange resin swaps out ions like lead and copper for sodium or potassium ions, pulling heavy metals out of the water. The combination handles chlorine very well, which is why PUR water tastes noticeably better than straight tap water to most people.
The filters do not remove bacteria, viruses, fluoride, or dissolved minerals like calcium and magnesium. If your water has any of those concerns, a PUR filter alone won't solve them. You'd need a different type of system — reverse osmosis for minerals and fluoride, or UV treatment for bacteria.
Key Takeaways
- PUR filters reduce chlorine taste and odor, and remove some lead and mercury, but do not remove bacteria, viruses, or fluoride.
- Different PUR models filter different things — a basic pitcher filter removes less than a faucet-mounted model with a longer cartridge.
- Filter cartridges need replacement every 2 to 3 months depending on your water quality and how much water you filter.
- PUR filters work best in homes with municipal tap water that already meets safety standards but tastes or smells bad.
PUR pitcher filters versus faucet-mounted models
PUR makes two main types: pitcher filters that sit on your counter, and filters that screw onto your kitchen faucet. Pitcher filters are cheaper upfront and portable — you fill them and wait a few minutes for water to drip through. Faucet-mounted filters cost more but give you filtered water on demand without the wait, and they take up no counter space.
The trade-off is filtering power. A PUR pitcher filter cartridge is smaller and shorter, so water spends less time in contact with the filtering material. A faucet-mounted cartridge is longer and denser, which means it can remove more contaminants and lasts longer before needing replacement. If you drink a lot of water or have specific concerns like lead, the faucet model usually performs better.
Pitcher filters work well if you drink a few glasses a day and mainly want better taste. Faucet models make sense if you use filtered water for cooking, filling bottles, or drinking throughout the day. Both require you to replace the cartridge regularly — ignoring that schedule means the filter stops working and water just passes through untreated.
What contaminants PUR removes and what it doesn't
| Contaminant | PUR Removes It | Notes |
|---|---|---|
| Chlorine | Yes | Removes taste and odor very effectively |
| Lead | Yes | Reduces lead; faucet models perform better than pitchers |
| Mercury | Yes | Reduced through ion exchange |
| Copper | Yes | Ion exchange removes dissolved copper |
| Some pesticides | Partial | Activated carbon catches some; not all pesticides |
| Bacteria | No | PUR filters do not kill or remove bacteria |
| Viruses | No | Viruses pass through; need UV or boiling |
| Fluoride | No | Requires reverse osmosis or specialized filters |
| Calcium and magnesium | No | These minerals pass through; cause hard water |
The most important thing to know: PUR filters work well for taste and odor, and they reduce some heavy metals. They are not a treatment for contaminated water. If your water has been flagged by your local health department, or if you suspect bacteria or serious contamination, a PUR filter is not enough. You need testing first, then a system designed for your specific problem.
How often to replace PUR filter cartridges
PUR recommends replacing pitcher filter cartridges every 2 months or after 40 gallons of water filtered, whichever comes first. Faucet-mounted cartridges last about 3 months or 100 gallons. These numbers assume average tap water quality — if your water is very dirty or has high sediment, the filter will clog faster and need replacement sooner.
You'll notice when a filter is getting tired: water flows more slowly through a pitcher, or the faucet filter produces a weaker stream. That slowdown means the filter is clogged and no longer filtering effectively. Waiting until water barely drips through defeats the purpose — replace it before you reach that point.
Keep track of when you installed the cartridge. Write the date on the filter itself with a marker, or set a phone reminder for 2 or 3 months out. Replacement cartridges are sold at most grocery stores, drugstores, and online. They cost between $5 and $15 depending on the model and where you buy them.
Storing filtered water in your refrigerator
Filtered water keeps longer than unfiltered tap water because the chlorine that acts as a preservative has been removed. Store PUR-filtered water in a clean, sealed container on a refrigerator shelf — not in the door, where temperature fluctuates. Filtered water stays fresh for about a week in the fridge.
If you leave filtered water on the counter at room temperature, bacteria can grow within a day or two. The filter removed chlorine, which means there's nothing stopping microbes from multiplying. Always refrigerate filtered water, and don't leave it sitting out. If you're filling bottles to take with you, fill them fresh each morning and drink them the same day.
Clean your PUR pitcher or faucet filter housing regularly — once a week is good. Rinse the pitcher with warm water and a soft cloth, and wipe the faucet mount. Mold and bacteria can grow on the plastic surfaces even though the filter itself is working. A clean pitcher means cleaner water and a longer-lasting filter.
When PUR is the right choice and when it isn't
PUR filters work best if you have municipal tap water that meets safety standards but tastes or smells like chlorine. They're also a good choice if you want to reduce lead exposure in an older home, or if you're concerned about specific pesticides that activated carbon catches. They're affordable, easy to use, and you see results immediately.
PUR is not the right choice if your water has been flagged as unsafe by your health department, if you suspect bacterial contamination, or if you need to remove fluoride or minerals. It's also not ideal if you have well water that hasn't been tested — well water needs a water test first to know what you're dealing with, then a system matched to those results. A PUR filter alone won't tell you what's in your water or fix serious problems.
If you're renting, PUR is often the best option because you can take the filter with you when you move. Faucet-mounted models unscrew easily, and pitcher filters are portable by design. Landlords usually don't object to temporary filters the way they might object to permanent systems.
Frequently Asked Questions
Does PUR remove all the chlorine from tap water?
PUR removes most chlorine taste and odor, but may not remove 100 percent of dissolved chlorine. For most people, the water tastes and smells noticeably better. If you need complete chlorine removal for a specific reason, ask PUR or check the product specs for your exact model.
Can I use a PUR filter if my water has been tested and found to have lead?
PUR reduces lead, but the amount depends on your model and how much lead is in your water. A faucet-mounted filter removes more lead than a pitcher. If your water has been tested and shows lead above safe levels, contact your local health department or water utility about treatment options — a PUR filter alone may not be enough.
How do I know when my PUR filter is no longer working?
Water flows slower through the filter as it clogs, and taste or odor problems may return. Replace the cartridge every 2 to 3 months regardless, because filters can look fine but stop working. Don't wait until water barely drips through — that means the filter stopped filtering long before.
Is filtered water safe to leave in a pitcher on the counter overnight?
No. Filtered water has had chlorine removed, so bacteria can grow if it sits at room temperature. Always store filtered water in the refrigerator in a sealed container. Fill bottles fresh each day and drink them the same day if you're taking them with you.
Do PUR filters remove fluoride?
No. PUR filters do not remove fluoride. If you want to remove fluoride from your drinking water, you need a reverse osmosis system or a filter specifically designed for fluoride removal.