How Often Should Your Water Filter Be Replaced?

Disclaimer: There are affiliate links in this post. At no cost to you, I get commissions for purchases made through links in this post.

As a homeowner, you’re responsible for ensuring your property is well-maintained. This includes regular upkeep of your home’s appliances and fixtures, including the water filter in your kitchen sink. So, how often should you replace your water filter?  

Replacing it too often can be wasteful and costly, but not replacing it often enough could mean contaminants making their way into your drinking water. Read on to find out the right replacement schedule for your needs. 

Why does the water filter need to be replaced? 

Once a water filter is installed at home, regular replacement of the filter when it becomes old or worn out is a must. This creates a dilemma in many people’s minds that how long should I leave the filter to do its job?  

What happens if I keep using it beyond its lifespan? The mistake here lies in not understanding the importance of the water filter.  

It is not like a regular milk pitcher that can continue to provide milk even if its pores are blocked by bits of old milk protein. The water filter should be left in for no longer than six months, after which it can become an obstacle to pure water intake. 

The first cause for concern with using worn out filters is to neglect the proof that it will not help you obtain clean and safe water. The dirt, sand and metal particles in the water become trapped by the pores in the filter when they pass through it.  

When these pores are clogged with contaminants, not only will they be unable to trap any more of these particles but also leave room for bacteria and virus particles to pass through the filter. Therefore, it becomes necessary to replace them after six months of usage. 

The second reason for switching off the water filter is that even though after 6 months it will not be trapping any more contaminants, you are still using up water.  

Once the pores in the filter get clogged, they cannot get back to their original state because they are stationary. This results in the filter becoming less effective by absorbing more water, thus wasting money. 

The final reason not to keep using the water filter is that it becomes a health hazard to use it even if you cannot see any contaminants getting through.  

By allowing the contaminants trapped on the surface of the filter to remain there, you are allowing the contaminants to contaminate other areas in your home. This could be dangerous for children or people who have respiratory problems. 

To avoid any of these scenarios from occurring, make sure that you replace the water filter every six months to get pure and healthy drinking water. 

How often should your water filter be replaced? 

The answer to this question depends on the type of filter you use in your home.  If it is a reverse osmosis filter, then you may need to change it every six months. Filters containing activated carbon usually only need to be changed once per year.  When you change your filter depends on a few factors: how much water you use, the quality of your local tap water and what it is being used for. 

If you have a refrigerator with an internal filter that needs changing, check the manual that came with it to see when this should be done. You can also contact the manufacturer by phone or email to ask when the filter in your refrigerator should be replaced. 

The Kitchen Sink 

One of three water filters is most likely attached to your kitchen sink. There are activated carbon, ceramic and diatomaceous earth filters available. Each has a different lifespan. If you have an activated carbon or ceramic filter, it may need to be changed every 6 months. However, a DE filter can last up to a year or longer. 

If your water is heavily chlorinated, you should replace the activated carbon filter more often. This is because chlorine from city treated tap water can wear down the carbon particles in the filter more quickly than usual, reducing its effectiveness over time. You may need to change it every 3 or 4 months. 

What to Do With Used Filters 

When it is time to replace a filter, don’t just throw your old one down the drain. There are several recycling options for used filters, including drop-off sites at local environmental companies and recycling centers. The EPA keeps a list of all the different recyclers across the United States that accept activated carbon or reverse osmosis filters. 

If you do not have access to a recycling center, you can contact the manufacturer of your water filter to find out if they will accept used cartridges. If that fails, you can place the old cartridge in with your regular garbage collection. 

The Bottom Line on Replacement Filters 

When it comes time to replace your water filter, make sure you choose one designed for the type of system you have- some filters work for both. Use the schedule provided by your manufacturer or dealer to decide how often it should be replaced and make a note to remember the replacement date. 

Don’t forget that you can always ask questions or contact anyone mentioned in this article by leaving a comment below. 

What kind of water filter do you have? 

When it comes to water filters, there are many options on the market. Knowing what kind of filter, you have will help you understand more about the product, including build quality and longevity. 

Filters can be categorized into 4 primary types:  

Jug filters (e.g., Brita)  

Jug filters, such as Brita or PUR, remove many contaminants and are easy to use. They typically have readable water-quality gauges and require no real maintenance other than changing filter cartridges periodically. However, they do not typically remove fluoride and aren’t as customizable in terms of contaminant removal. 

Faucet-mount filters  

Faucet mounted filters are typically not as easy to use or maintain (more frequent filter changes) but can be good for emergency situations. However, they typically do not remove fluoride like the other types mentioned above do. 

Under-sink filters (AKA reverse osmosis/RO systems or RO faucet mounted filters)  

Under-sink filters, such as RO systems or RO-type faucet mounted filters, are great for treating a large volume of water in one place.  

They typically have multiple stages of filtration and can handle both drinking and cooking needs.  

However, they require installation under the sink and must be used with dedicated lines to avoid contamination from use of the cold-water line for drinking/cooking purposes. 

Countertop gravity-fed filters (e.g., Berkey, most ceramic units). 

Countertop units (e.g., AquaRain, etc.) are typically more customizable in terms of contaminant reduction and require little to no maintenance.  

The Berkey gravity-fed filter is a good alternative that requires no electricity, provides more gallons per day than commercial units (e.g., AquaRain, etc.), and has a very high contaminant removal rate (> 99%). 

If you use bottled water as a primary source for drinking and cooking, this type of filter is a great option because it can remove contaminants (including fluoride) that you otherwise would be consuming in the purchased water. 

If you already have an RO system or faucet-mounted filter, it is important to know that not all filters are created equal.  

Some filters claim to remove contaminants like fluoride, arsenic, etc., but do not actually remove them.  

The most common way this occurs is by substituting an inorganic (i.e., not carbon-based) element like granulated clay, granulated carbon, etc. in the filter cartridge in place of a true reverse osmosis (RO) membrane that filters contaminants via chemical and physical processes.  

The chemicals used to make these fake RO membranes are usually inferior or lack proper testing for safety and efficacy. 


  • It is also important to note that RO filters require normal maintenance like other types of filters (i.e., replacement cartridges periodically). Additionally, some RO systems can’t handle the build-up of minerals over time. These units will need periodic descaling or de-liming via cleaning by a water treatment professional (not typically covered under warranty). 
  • If you need to purchase a filter for drinking/cooking purposes, we recommend purchasing the RO system as it is the most customizable and best option. If you already have an RO system or faucet-mounted filter, make sure that the replacement filters you use remove contaminants like fluoride.  
  • Avoid purchasing or using RO systems or filters that use granulated elements in the cartridge over a true RO membrane. 
  • If you are looking for an under-sink system, make sure to purchase one with multiple stages of filtration. These are typically more customizable and better at removing contaminants like fluoride than units with fewer stages.  
  • Be sure your RO system or under-sink unit has a working warranty and can handle the build-up of minerals over time. 
  • If you need to purchase a faucet mounted filter, we recommend PUR as they provide good value for money and typically remove contaminants like fluoride. 

How do you know when it is time to replace your water filter? 

It’s a good idea to replace your water filter every year. There are a few telltale signs that it may be time to get a new one. Check if any of these apply: 

If the flow rate is slower than usual, then the cartridge needs replacing. If you have started seeing blackish or brown particles in your filtered water, then the cartridge needs replacing. If your faucet still has residue after running through the filter, then it’s time to replace the filter for sure! 

If you get your water from a private supply or a well, then you will have to test it by using a TDS meter. If the ppm level is more than 300ppm in total dissolved solids, then you will need to replace your water filter. Also check the pH levels in the filtered water. If they are not within the desired range of 6-8, then it’s time for a new cartridge. 

If you have an under-sink unit installed in your kitchen for filtering water, you should change the cartridge every six months. Over this time, the resin will have absorbed most of the contaminants from your water. 

If you don’t do any of these things, then you may end up drinking contaminated water that can harm your health. To avoid this, order a new cartridge every month. This way it will always be ready to use. 

Where can you find a replacement for your water filter? 

There are only a few places that offer replacement filters for your home water treatment system.  

The first place you can check is the manufacturer’s website. Some manufacturers offer customer support, product support and warranty information online.  

You can also purchase filters directly from them or another retailer. If you do not like ordering products on the internet, you can also look for a local water treatment dealer. 

This type of dealer provides new filters and cartridges for your home system. They may even offer other replacement parts such as valves or O-rings.  

The benefit of buying from a local water treatment dealer is that they will have an expert who can diagnose and repair any issues with your system.  

If you have a well, you could find a dealer by looking in the phone book under “Water Filter Dealer.” You can also check with local water treatment equipment dealers or appliance stores for this information. 

FAQs About How Often Should Your Water Filter Be Replaced

A water filter is used to remove impurities from the water. The most common type of filters is activated carbon, deionization and reverse osmosis.  

The list varies depending on where you live and what is in your plumbing system: chlorine (added for sanitation), fluoride (used to improve dental health), pharmaceuticals, pesticides, dissolved minerals, heavy metals. 

It is recommended that the filter be changed every 6 months. 

Yes, but you might get wet! It is recommended that you disconnect the filter from the hose or tap it on something solid before trying to remove the old filter. Then just snap the new one in, twist clockwise until secure and you are ready to go! 

If you have an ice maker on your fridge, then no. You can either turn off the water at the shutoff valve under your sink or you may disconnect the icemaker line from the filter by pushing in on both ends of the tube until it comes apart. Then remove the end that goes into your refrigerator and snap in a new cartridge. You can then connect one end of this piece to your fridge so you can make ice while replacing your filter. 

There are several ways to do this depending on the type of filter you have. Push down on the bottom of the housing while pulling up to release it from its locked position, then slide out. You can also just pull straight up with one hand located in the spot provided in the lid and push down on the bottom with your other hand. It should just slide out easily. 

If you have a wrench, it will be helpful in removal of your filter. Because most filters are designed to fit several different housing units, there may or may not be a groove on one side of the filter cap. If there is no groove, you can just put the wrench around the cap to keep it from turning. If there is a groove, then you will need to place the wrench so that it contacts both sides of the filter housing. 

Once you have done this, you may be able to remove your filter by turning counterclockwise until it comes free. Reverse the process to put the new filter in. 

If you have a refrigerator with an automatic icemaker or water dispenser, the manufacturer may recommend that you change the water filter every six months. For a basic faucet-mounted filter, follow the replacement schedule suggested by the manufacturer. If it has been more than six months since you replaced your filter, you should replace it now. 

Think about how many water filters have been used over the years. If one filter has the capacity to last six months or more, think of all that garbage that can be prevented from being created! 

Most faucet-mounted filters can be identified by looking at the underside of the filter head. There should be a sticker with some or all the following information: 

  • The brand name (PUR, Brita, etc.) 
  • The model numbers 
  • A series of letters and/or numbers used to identify individual filters for that product line 

If you cannot find the model number on the underside of your filter head, it may be molded into the body of your faucet-mounted filter. 

A small removable sticker with a barcode and/or series of numbers is commonly used to identify specific models by product line. The sticker can usually be found on the top or side of the plastic housing that surrounds your filter. 


Replacing your water filter every six months is a good rule of thumb for most households. For those with especially hard-to-treat tap water, it may be necessary to replace the filters more often than that.  

In these cases, it’s best to consult an expert at a local hardware or home improvement store about what type and size of filter you should purchase. 

Related Posts

Why Trust Us

You will find what you are looking for at Largo Bar and Grill. From classic to luxury brands, you'll find both. We will help you to select appliances that fit your needs, budget and lifestyle. Whether you want to stop by to learn more — or plan to make a major purchase — we’ll treat you like family and assist you every step of the way. Shop with us today to receive friendly and experienced help along the way.