Wondering which water filters and membrane you should purchase for your RO filtration system?
Find the exact replacement filters for your RO system with our easy-to-use Filter Finder tool. Simply enter your brand and model number.
If you're not sure of your RO system's brand and model number, here are three steps to help you determine which RO system you have so you can buy the correct replacement filters.
STEP 1: FIND BRAND AND MODEL OF RO SYSTEM
The best option and most accurate way to get the right replacement filters is to identify the brand and model number of your current system.
STEP 2: SELECT WHICH MODEL RESEMBLES YOURS
If you're unable to find your RO system's brand and model information on the system itself, select the graphic below that most closely resembles your RO unit. When you click the "learn more" button, you'll be able to see which replacement filters are avilable for your RO system.
If none of the four systems below match your system, go to step 3.
STEP 3: CALL US
If you've tried the two steps above and still cannot figure out which filters you need, please give our customer support team a call. We're avaialble Monday-Friday 9 am to 5 pm Central Time: 877-377-9876.
To simplify the filter replacing process, we offer replacement kits that bundle everything needed for the annual filter replacement. Because the RO membrane typically only needs to be replaced every 2 years, we offer replacement kits with the membrane (year one) and just the sediment and carbon filters and no RO membrane (year two).
SEDIMENT PREFILTER
This pre-filter stage is designed to strain out sediment, silt, and dirt and is especially important as the sediment filter protects dirt from getting to the delicate RO membranes that can be damaged by sediment. Learn more about sediment filter. Change this filter every 6-12 months, or possibly more often in areas with very high turbidity in water.
CARBON PREFILTER
The carbon filter is designed to remove chlorine and other contaminants that affect the performance and life of the RO membrane as well as improve the taste and odor of your water. Change the carbon filter every 6-12 months. This will help to ensure membrane life and quality.
REVERSE OSMOSIS MEMBRANE
The semi-permeable RO membrane in your RO system is designed to allow water through but filter out almost all additional contaminants. Change the reverse osmosis membrane every 24 months.
POST FILTER
In a four-stage RO System, a final polishing carbon filter will “polish” off the water to remove any residual taste and odor. Change this filter every 6-12 months to ensure quality water. Do not wait until taste is a problem.
When your new replacement filters arrive, follow the instructions on how to change the RO filters and membrane. Note that when changing RO filters, it is strongly recommended that you sanitize and clean your RO system at the same time.
To maintain your system, we offer a few simple maintenance tips. And for answers to common Reverse Osmosis system questions, check out our RO Troubleshooting Guide
If your RO system is getting older, you may be able to convert your existing system with a Reverse Osmosis "conversion kit".
RO conversion kits provide a simple way to not only update your system, but also break away from having to buy expensive name-brand filters and parts. Conversion packages include the new manifold, RO filters, and extra tubing. You can keep your current faucet and RO tank. Setting up the new conversion kit is about as simple as connecting the tubing from your existing faucet and tank to your new manifold (part that holds the filters), and you're ready to go!
And if you're shopping for an entirely new Reverse Osmosis drinking water system, here are suggestions on what to know before purchasing a reverse osmosis system that might prove helpful. See highly-recommended RO drinking systems below.
We've been in the water filtration industry for more than 20 years and are proud to carry one of the largest online inventories of membranes, filters and replacement parts for reverse osmosis, ultraviolet and a variety of other water filtration systems.
RO System Identification Frequently Asked Questions
How do I identify my reverse osmosis system brand and model?
The most reliable place to look is the manifold — the plastic or metal block that holds your filters in place. The brand name and model number are usually printed on a sticker on the back or side of the manifold. Labels on individual filter cartridges do not indicate the system brand or model. If there's no sticker, check any paperwork or owner's manual that came with the system, or compare your unit visually against the system photos in our RO system identification guide.
Where is the model number on my RO system?
Check the back or underside of the manifold — the component that connects and holds the filter housings together. There is usually a small sticker with the brand name and model number. If no sticker is visible, the owner's manual may list it, or you can use our visual identification guide to match your system by appearance. Once identified, use our Filter Finder to pull up the correct replacement kit for your model.
Can I use generic replacement filters instead of brand-name RO filters?
Yes — for most RO systems, high-quality compatible replacement filters perform just as well as expensive OEM filters at a fraction of the cost. ESP Water carries compatible replacement filter kits for dozens of brands including GE, Culligan, Watts, EcoWater, and more. The exception is some proprietary systems that require a conversion kit before universal filters can be installed — a one-time upgrade that permanently ends your reliance on expensive brand-specific replacements.
How do I know which replacement filters fit my RO system?
Identify your system's brand and model number from the manifold sticker, then search using our Filter Finder by Brand & Model. If you cannot find the brand or model, use the visual matching guide on our Identify My System page. Once matched, ESP Water provides complete replacement kits covering your sediment pre-filter, carbon block pre-filter, RO membrane, and post-carbon polishing filter — everything needed in a single order.
What is a reverse osmosis conversion kit and do I need one?
An RO conversion kit replaces the filter manifold on your existing system so you can use affordable universal filters instead of expensive proprietary OEM replacements. You need one if your current system uses brand-specific filters unavailable from third-party suppliers. The conversion keeps your existing storage tank, tubing, and faucet intact — only the manifold is replaced. Learn more about converting your existing RO system to save money, and browse our RO replacement filters and parts
How often should I replace reverse osmosis filters?
Sediment and carbon pre-filters should be replaced every 6–12 months to protect the RO membrane and maintain water quality. The membrane itself typically lasts 2 years. The post-carbon polishing filter should be replaced annually. Neglecting filter changes is the leading cause of premature membrane failure. For full step-by-step instructions see how to change RO filters and membranes, and sign up for a filter subscription plan so you never miss a change.
Reverse
Osmosis
RO Systems
Ultraviolet
UV Systems
