Last updated: August 23, 2021

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Welcome to our big drinking water filter test 2021. Here we present all the drinking water filter systems that we have tested in detail. We have compiled detailed background information and added a summary of customer reviews on the internet.

We would like to make your purchase decision easier and help you find the best drinking water filter system for you.

You will also find answers to frequently asked questions in our guide. If available, we also offer interesting test videos. Furthermore, you will also find some important information on this page that you should definitely pay attention to if you want to buy a drinking water filter system.


  • A drinking water filter system is indispensable in many households and gardens. The water has too much lime, bacteria or is too contaminated for everyday use, so that the purchase of a water filter system decisively improves the quality of the drinking water.
  • Basically, a distinction is made between drinking water filters with reverse osmosis and filter systems with activated carbon. You have to decide for yourself which advantages you see in the respective filter technology.
  • What is important is that the treatment of drinking water for the home and garden is generally sensible and that it does not initially matter how the water is filtered.

The Best Drinking Water Filter System: Our Picks

Guide: Questions you should ask yourself before buying a drinking water filtration system

Who needs a drinking water filtration system?

First of all, you should know that the Federal Environment Agency regularly tests water in Germany for pollutants. This means that further filtration of your drinking water is not necessary for the time being. According to the German Drinking Water Ordinance, water must be constantly monitored and meet high quality standards.

However, this testing only takes place within the framework of public water distribution. For you, this means in detail that this control and requirement only applies up to the house or flat connection.

It should be noted that the drinking water still flows through the domestic installation. The domestic installation means all pipes, devices and fittings, and you as the tenant or owner are responsible for their suitability.

Tischfilter mit Wasserglas

You can filter your drinking water either with a system connected to the tap or with a table filter. (Image source: / 106433531)

You need a drinking water filter system if you have defective pipes, fixtures or fittings. Old water pipes can contaminate drinking water with heavy metals, germs or bacteria and make it unsuitable for everyday use.

Buying a system for drinking water can also make sense if you are concerned about traces of drug residues or pesticides, because these can be present despite strict controls. Although the limit value is met by the qualitative requirements, it is not completely removed.

Did you know that 3.4 million people die every year because of contaminated water?

Unfortunately, access to drinking water is not as self-evident everywhere as it is in Germany. Worldwide, 844 million people have no access to clean drinking water.

Another reason for buying a drinking water filter system can be that you want to save yourself the hassle of carrying water boxes. This would also save you money in the long run.

What alternatives are there to drinking water filter systems?

There are inexpensive alternatives to drinking water filter systems that are often expensive or at least difficult to install. Although these water filter systems have their advantages, you may want an alternative.

Table jug filter

This alternative can be the table jug filter. Especially in the garden, a table jug filter is very practical, because it provides you with clean water to drink all the time in a quick and complicated way.

The jug filter often has an activated carbon filter, which removes limescale and taste disturbances. However, the tap water is not completely purified, i.e. other pollutants remain in the water.

The problem here, however, is that the water filter cartridges have to be replaced quite frequently and regularly. If the cartridge of the activated carbon filter is not changed properly, germs will quickly develop. You can buy replacement filters online or in a shop.


A distiller heats the drinking water to about 100 degrees Celsius. The water is evaporated, which is then collected, cooled and returned to its liquid state.

This method filters out all pollutants that have a boiling point below that of the water, while the rest remains in the distiller. The purity of the drinking water is thus very high.

The problem is, however, that distillers have a very high energy consumption, so that the running costs increase as a result. You also have to clean a distiller after each use.

How does a water filter work and what is filtered?

There are different ways in which water is filtered.

In general, the purpose of a water filter is to make the tap water cleaner and healthier for you after it has been filtered.

The most important ones are listed below.

Activated carbon filter

An activated carbon filter for filtering water removes impurities from the water, including heavy metals, chlorine, pesticides and pharmaceutical residues.

In this process, the water is filtered through the activated carbon monoblock at high pressure. The activated carbon monobloc consists of sintered activated carbon or activated carbon baked under high temperatures, and it has to be changed about every 6 months.

Reverse osmosis

With reverse osmosis systems, the drinking water is treated differently. The water is forced at high pressure through an almost impermeable membrane through which only small water molecules can pass.

This water treatment process has the advantage that the water attains a purity level of over 99.9%, although this also removes all minerals.

Table jug filter

Table jug filters are primarily used for softening and descaling water. Most table jug filters have an activated carbon filter and sometimes an ion exchange.

The unfiltered water is filled into the upper part and then passes through the filter into the lower part of the jug. In doing so, the filter serves its purpose by removing pollutants and limescale.

How much does it cost to filter water?

You probably already suspect that the actual cost of filtering water is higher than just the initial cost of a drinking water filtration system. There are 3 main points to consider here.

  1. Purchase costs of a drinking water filter system
  2. Costs for the filter cartridge
  3. Operating costs

You can get very cheap drinking water filter systems with activated carbon filters from 24 euros on Amazon. The same applies to drinking water filter systems with reverse osmosis, which you can also get online for as little as 49 euros. However, if you value good quality, you should spend more. The installation of these water filter systems is very simple and is usually done in person.

Type costs
Activated carbon filter system from approx. 24 GBP
Reverse osmosis system from approx. 49 GBP
Filter cartridges from approx. 6 GBP
Operating costs depending on the filter system

You can buy cartridges for the water filters from 6 euros on Amazon, for the water filters shown in the ranking you can buy the cheapest filter cartridge online from 22 GBP.

The operating costs depend on the water filter system, as the filter systems are very different. You will need to factor in the cost of any electricity consumption and increased water usage.

As a drinking water filtration system is a long-term and expensive purchase, you should think carefully about what the water filter should be able to do and whether you are prepared to bear the long-term costs.

Decision: What types of drinking water filter systems are there and which one is right for you?

As already mentioned, there are different drinking water filtration systems. The aim of a drinking water filter system is to clean the contaminated water that flows into it. Depending on the water filter system, minerals are enriched during this process.

Basically, all water filters work in the same way, as they all have the same objective. However, a distinction is made between different drinking water filter systems.

There are drinking water filter systems with:

  • Activated carbon filter
  • Reverse osmosis

All these water filter systems have special features and are particularly suitable for different needs. We will show you these in the following.

What distinguishes a drinking water filter system with activated carbon and what are its advantages and disadvantages?

A drinking water filter system with activated carbon can retain large and organic water constituents, including plant treatment agents and chlorine. Most systems with activated carbon filters are installed on or under the sink.

As the activated charcoal monobloc takes care of filtering the water, the water is freed from the pollutants, but the minerals are retained. The filter needs to be changed when the monoblock is fully loaded. You can recognise this by the fact that the water flow is noticeably reduced.

  • Water is freed from pollutants
  • minerals are retained in the water
  • installation possible as an on-sink and under-sink version
  • No filtration of lime or nitrate
  • filter cartridges need to be changed every 6 months

For this type of filter to work, contact with water is necessary, i.e. the activated carbon monobloc actively absorbs the pollutants. The water must flow slowly through it, which happens through the block filter.

You can buy replacement filters online from Amazon, for example.

What distinguishes a drinking water filter system with reverse osmosis and what are its advantages and disadvantages?

A reverse osmosis system has pumps that force the water through an almost permeable membrane. This means that only small water molecules can pass through, ensuring super-pure water.

The reverse osmosis process is beneficial because the osmosis filters actually filter out all pollutants:

  • chemical substances, such as plant treatment agents or drug residues
  • Larger substances, such as nitrate, heavy metals or phosphate
  • Minerals, such as calcium and magnesium

However, these water filtration systems are very complex, so regular use is very important to avoid bacteria build-up. In addition, many reverse osmosis systems have a high water consumption. Depending on the model, up to 10 litres of water are needed to produce one litre of osmosis water.

  • Water is freed from all pollutants
  • saves electricity because water is purified by means of pressure
  • Very maintenance-intensive
  • high water consumption possible
  • minerals must be added to the water after filtering

You can buy osmosis filters online via Amazon, but you won't often need replacement filters for the membrane as they are very durable.

Buying criteria: Use these criteria to evaluate and compare a drinking water filter system

Do you want to buy a drinking water filter system? In the following, we would like to show you which criteria you can use to compare and evaluate water filter systems. This will make it easier for you to decide whether a certain product is suitable for you or not.

In summary, these are:

  • The type of filtration
  • The replacement of the filter cartridges
  • The suitability of the system for fittings
  • The size and weight of the filter system

In the following paragraphs you can find out what the individual purchase criteria are and how you can classify them.

Tap water filtration (which type of filtration)

Depending on the type of contamination in the drinking water that you want to combat with the drinking water filter system, the type of drinking water filtration will play a role in your purchase decision.

Activated carbon filter systems are usually a little cheaper to buy, and they also filter out most of the impurities in the water. Reverse osmosis systems, on the other hand, are usually more expensive and have a higher water consumption.

However, most reverse osmosis systems have an integrated mineral filter so that the minerals previously removed are returned to the water.

Both types of filtration have their own advantages, in various online shops you can find out about the opinions of other customers or ask your own questions about the type of filtration.

Exchange filter cartridges

You should know that a drinking water filter system can only work well as long as it is maintained. This means that you have to take a look at the filter cartridges before buying a water filter system.

Filter cartridges usually have to be changed every 2-3 months, at the latest after 6 months. When buying a drinking water filter system, it is usually already pointed out that the cartridges have to be changed at regular intervals.

When buying a filter cartridge, you should pay attention to the brand of the water filter. Changing a cartridge is quite easy, instructions are always included.

Since filter cartridges can be quite expensive, you should include their purchase or regular replacement in the purchase of your drinking water filter system.

Suitability for which taps

When buying a drinking water filter system, you should consider how it will be connected.

Most drinking water filter systems are easy to install: The water filter systems presented in the ranking can all be installed by yourself without much effort.

You only need to check whether the filter system is suitable for your taps. Most suppliers of drinking water filter systems will send you a universal adapter for the tap, or at least offer different adapter sizes. If your size is not included, you can ask the supplier if they can help you with your tap size.

Size and weight of the drinking water filter system

Both the size and the weight of a drinking water filter system are crucial when buying.

Type Size Weight
Activated carbon filter system from approx. 11x12x31cm approx. 2.7kg
Reverse osmosis system from approx. 20x36x8cm approx. 2kg

If you have a large garden or a large kitchen, or wherever you would like to install the drinking water filter system, you are quite flexible when it comes to purchasing it. However, if you have less space, you will have to deal with the size and weight.

Facts worth knowing about drinking water systems

Water filtration for wells

Well water is water that is taken from a well. These are fed by springs or groundwater.

Since not every well in the garden draws drinking water, water filtration is particularly important here. Basically, you can choose between activated carbon filtration and reverse osmosis. There is no special well water filter.

How useful is it to filter drinking water?

On average, the human body consists of 55% water. While the proportion was 70% at the beginning of life, it drops to just 45% in the course of life.

This is why water is so important for human survival, because without drinking water a person can only survive for 3 days. It is important to know that drinking water is everything with which humans have more than just fleeting contact, i.e. water for personal hygiene, cleaning food and other points of contact in daily life.

A drinking water filtration system is used to filter the water for bacteria, viruses, medical residues, chlorine and lime. This is the only way to ensure that you have clean and healthy drinking water.

Did you know that half of all Germans suffer from a lack of fluids every day?

Actually, a person should drink an average of 3 litres of water per day. Moreover, access to clean drinking water encourages you to drink more.

Although drinking water in Germany is strictly tested, there can still be impurities in the water, as this testing only covers the municipal service network.

It makes sense to filter the drinking water through a water filtration system, as this saves money in the long run, thus saving the purchase of mineral water. It is also beneficial for the environment, as tap water has a lower CO2 footprint than mineral water.

Who installs the water filter system?

You can install most drinking water filter systems yourself with the help of instructions. Professional help from a plumber is not necessary.
The only thing you have to consider when installing your water filter system is whether it is an under-sink unit or an over-sink unit. Then, depending on the installation location, you must create the appropriate space and can still install it easily.

Most reverse osmosis systems are larger and many have an additional tank, but this does not affect the ease of installation.

Image source: / 56598411