A filtered water bottle is an excellent tool for improving the taste of tap water or filtering out harmful bacteria in spring water while traveling. In addition to offering convenience, filtered water bottles can help the environment by reducing the consumption of plastic water bottles.

There are two main types of filtered water bottles: those that improve the flavor of already drinkable water (like tap water) and those that make water found in nature or in foreign countries safe to drink. The latter typically costs more, and the filters for this type of bottle may not last as long. Filtered water bottles designed for filtering tap water can remove the unpleasant taste of chlorine found in most tap water in the U.S.

The filters in water bottles are designed to remove chemicals that affect taste (like chlorine) or to remove bacteria that can be harmful to health.

A carbon filter is the most common type of filter. It uses active carbon to remove impurities. Active carbon is porous, which allows it to collect particles as water passes through. Notably, as more particles and impurities are removed over time, the filter becomes clogged. This can hinder water flow and reduce the effectiveness of the filter. As a result, carbon filters must eventually be replaced.

Also known as UV filters, these are less common and require batteries. They are also more expensive, and the cost of batteries adds up. While UV filters cannot treat chemicals in water, they are more reliable when it comes to removing bacteria and viruses from water.

The best (and most expensive) filters available combine carbon and UV filters or additional filtering layers. The nice thing about water bottles with combination filters is that even if the battery runs out, you can still filter a good deal of harmful bacteria with the carbon filter.

Straw filters can be challenging to use, as the filter creates more resistance than a normal straw. What’s more, as the filter becomes clogged, it becomes difficult to draw water out. However, some water bottles with straw filters are soft-sided, allowing you to squeeze as you drink for easier access.

These must be pressed down or pumped. The push or pump design is not for everyone, as a decent amount of hand strength is required to use these bottles.

These are among the simplest filter designs. Water is filtered as you pour it through; after a few minutes, your water is drinkable.

These filters are quite straightforward. You press a button, wait a few seconds, and your water is filtered.

Filtered water bottles range in size from approximately 16 to 26 ounces. How much water you need depends on the task at hand. For camping, a larger bottle may be best. If you’re hiking long distances, however, you may not want to carry the additional weight.

If you plan to carry your water bottle in your backpack or on a long commute, opt for a lighter bottle. Must UV filter bottles tend to weigh more due to the filter and batteries. The material of the bottle can also have a significant impact on weight, with plastic bottles weighing the least. Filtered water bottles usually range from 3.5 to 10 ounces.

Filtered water bottles are usually made of one of three primary materials: plastic, metal, or glass.

• Plastic filtered water bottles are lightweight and durable, though some people find the plastic gives the water an unpleasant taste — particularly if the bottle becomes warm. Always look for BPA-free plastics. Some thicker plastic bottles can be quite heavy.

• Metal bottles are heavier than plastic bottles, but they tend to look and feel nicer, and most people don’t notice an unpleasant flavor.

• Glass bottles are generally the heaviest option due to the thickness of the material. People often enjoy the lack of taste that comes with glass bottles. Most have a rubber or silicone coating to prevent breakage.

Some filtered water bottles have a straw system that facilitates both filtering and drinking. Others have a traditional opening that requires you to tilt the bottle to drink, which is often more convenient than a filter straw.

Between $20 and $40, you’ll find filtered water bottles with straw carbon filters that are typically made of BPA-free plastic. The number of uses for these filters is often limited, and the filters may be difficult to replace.

Mid-range bottles for $40 to $60 offer carbon filters, UV filters, or combination filters for high-quality filtration. These are often made of plastic, metal, or glass.

Filtered water bottles in the $60 to $120 range tend to excel at removing most harmful bacteria and viruses from water and are best suited for outdoor use or international travel.

• Clean your filtered water bottle regularly. Even though these bottles remove harmful particles, bacteria can still build up on the straw or in the opening.

• Don’t ignore the filter expiration date, even if the filter isn’t clogged yet.

• When comparing prices, don’t forget to factor in the cost of batteries and replacement filters down the road.

• Filtered water bottles cannot remove salt from salt water and should only be used with fresh or tap water.

• If lead is a major concern for you, look for filtered water bottles that specifically target lead. This is common with most activated carbon filters.

For a high-end filtered water bottle that will last for years, consider the Lifesaver Bottle 6000 Ultra Filtration Water Bottle. With a filter that can handle over 1,500 gallons and can process 25 ounces in under a minute, this is an ideal choice for campers and hikers. A less-expensive option that works well for international travel is the Purewell Water Filter Bottle. While the straw takes some effort to draw water, this is a reliable and affordable choice for filtering tap water abroad.

Q. Can filtered water bottles remove heavy metals from water?
A. It depends on the filter, but many carbon filters are capable of removing common heavy metals such as copper and lead.

Q. Can you pour filtered water from the bottle to another container?
A. As long as the water is already filtered (and doesn’t need to be pulled through a straw), you can safely pour your filtered water into other containers.

Q. Are filtered water bottles dishwasher safe?
A. It varies from one model to the next. In most cases, filtered water bottles should be hand washed with soap and water.

Q. What’s the difference between a filter and a purifier?
A. While both serve the same purpose — removing harmful elements from your water — a purifier adds an extra level of protection by removing bacteria and viruses. Many bottles advertise a two-in-one system that filters and purifies for additional peace-of-mind.