Hey Lolly! Thanks for asking.

They say on their Amazon Page that it filters 264 gallons. I just did a little bit of math before I went, so: If you (ideally) want to drink 8 glasses a day of water, thats somewhere between 48–64 ounces, the lifestraw will filter 33,792 ounces in its filter lifetime, which evens out to 528 days of 64-ounce consumption. So, you’d be good for the whole year and then some. There is a bit of a plastic-y taste, however, which some people don’t like.

BUT! Pro tip: You can remove your filter (just by popping it it out) and use it like a normal water bottle. I’ve being doing that in both Portugal and Spain where the tap water is drinkable! Makes the filter last longer and gives you more room in the bottle to carry water on trips.

Let me know if you have any other questions!