Aquasana and Culligan both sell under-sink filters, but you buy and install them in different ways. Aquasana sells online, and most people fit the system themselves. Culligan works through local dealers, who usually come to your home and install it. When we compare Aquasana vs Culligan below, we look at what each filter removes and also at how much help you get after the purchase.
What you actually pay
If you’re pricing an Aquasana under sink water filter, the numbers are public. A Claryum 3-stage replacement set costs $83.99 on Aquasana’s page, and Aquasana recommends a new set about every six months. Two sets a year add up to roughly $168 in cartridges, and that is before you pay for the system. Aquasana has been owned by A.O. Smith since 2016.
The Culligan reverse osmosis system cost is harder to find. According to TapWaterData, culligan.com does not list prices, so you contact a dealer, and the dealer often visits your home before giving a price. The figures you see online come from third parties. HomeGuide estimates $1,050 to $1,700 for an installed under-sink RO unit and $2,500 or more for smart and tankless models. We would use these numbers only as a rough guide and ask the dealer for a written quote. Culligan also rents systems, usually for $10 to $30 a month with maintenance included.
Getting it installed
You install Aquasana yourself. Check your sink before you order the Aquasana 3-stage under sink water filter (the 3-Stage Max Flow model), because it comes with a separate faucet. If the sink or countertop has no free hole for it, you will need to drill one.
Culligan under sink water filtration is installed by an authorized dealer, and the visit usually takes an hour or two. TapWaterData also reports that the warranty terms limit DIY installation. For people who don’t want to deal with plumbing, this is convenient. We still suggest reading the warranty for the specific model before you agree to anything.
Filters, upkeep, and minerals
How the water is filtered matters more than the brand. Many Culligan under sink water filter systems for drinking water use reverse osmosis (RO). The RO membrane removes many dissolved substances, minerals among them, and some of the water goes to the drain. Some models add minerals back after filtration. With RO you also maintain several filters and a membrane, and each has its own replacement schedule. On a rental, the dealer may handle this. If you buy the system, ask the dealer what maintenance the price includes.
Aquasana’s Claryum system does not use reverse osmosis. According to Aquasana, its filters keep beneficial minerals in the water. Maintenance means replacing the whole set, pre-filter included, about every six months. It is a simpler routine than RO, but you still need to plan for the cost.
Where we fit in
Woder is our brand, and we sell under-sink filters too. Below is how our system compares with the other two, and when it is not the best choice.
Like Aquasana, Woder is installed by the owner. Direct Connect attaches to the existing cold-water line and uses the faucet you already have, so you don’t drill a new hole. Basic tools are enough for the installation. You change one cartridge instead of a set of filters, and the cartridge is rated for a year under the stated warranty conditions. When we wrote this, the WD-G4-REP replacement cost $48. Our Selective Filtration™ media targets specified contaminants and keeps calcium and magnesium in the water. The system has no drain line and does not need a power cord.
When you compare brands, check what each certification actually covers. Woder’s base Gen4 Advanced media has WQA Gold Seal certification to NSF/ANSI 42 and 372 as sold. Our other claims, including lead and PFAS, are based on testing by CLB Labs. This is independent testing, and it is not the same thing as WQA certification, which is why we list them separately. Our team can send you the performance data before you decide.
Woder is not a reverse osmosis system, and it does not reduce total dissolved solids the way RO does. If your water test shows that you need TDS reduction, or you want a dealer to install and maintain the system, Culligan suits you better.
So which one?
In Culligan vs Aquasana, each brand works for a different kind of buyer. Culligan makes sense if you want RO and a dealer who installs it. Aquasana suits people who buy online and are ready to install a multi-stage system with a separate faucet. If you want to keep your current faucet and replace only one cartridge a year, compare Woder with the other two. This article covers under-sink systems only; an Aquasana vs Culligan whole house filter comparison involves different equipment and prices, so we don’t cover it here.
If you are not sure yet which type of filter you need, read our guides on how to choose a water filter and the types of water filters. For other brands, see our comparisons Aquasana vs Waterdrop and Culligan vs Kinetico. All of our under-sink filters are listed in the catalog.
Frequently asked questions
Is Aquasana better than Culligan?
Not for everyone. Aquasana is a good fit if you are comfortable installing a filter yourself. Culligan costs more, and the extra cost pays off if you want professional installation and service or need reverse osmosis. In both cases, compare the performance data for the specific models.
Is Culligan worth the cost?
It can be worth it if you value professional installation and regular service. If you mainly want better taste or need to remove one specific contaminant, a simpler under-sink filter will usually cost less. Ask the dealer for a written quote that lists equipment, installation, service and rental terms separately.
Does Aquasana remove minerals?
According to Aquasana, Claryum filters keep beneficial minerals. RO systems remove most dissolved minerals, although some models have a remineralization stage.
Can I install a Culligan under-sink system myself?
If you want a Culligan water filter under sink, plan on an authorized dealer doing the installation. TapWaterData reports that installing one yourself may conflict with the warranty terms, so read the warranty for your model first.
Does a Woder filter replace reverse osmosis?
No. Woder uses Selective Filtration, not reverse osmosis. It targets certain contaminants and keeps minerals in the water, but it does not reduce total dissolved solids the way an RO system does.
