Is Tap Water or Bottled Water Better for Coffee?

Last Updated on July 6, 2023 by Barry Gray

Coffee is important to me. I’m sure you have already realized that.

But even though I feel pretty settled as to what I want from a coffee, I’m always up for some experimenting.

Usually, I talk about different beans and how they change their flavor, but this time I plan on looking at something that’s integral to coffee: the water.

Now, there are options when it comes to water, but the primary focus is on whether tap water or bottled water is best for coffee. So, which one is it?

If you have poor tap water, then bottled water may be best. But not all bottled water is the same, with some being of inferior quality. If your tap water is pleasant to drink, then you can easily use it for your coffee, and I wouldn’t worry too much about then using bottled water.

What you can take from all this is that the issue of water is not as straightforward as you may have hoped. So, let’s start working through different aspects of your water options and see if I can clarify things for you.

tap water or bottled water for coffee

Does the Water You Use Make a Difference?

But before I go ahead and look at both tap water and bottled water, let me assure you that the water you use does make more of a difference than you perhaps expected.

The mistake people make is thinking that all water is the same. It’s not.

Even if you try different bottled water and drink it, you will notice a slight change in taste. Evian is not the same as Volvic, for example, so if you do have those taste changes in the water, you can imagine what it may do to your coffee. 

And yet, I know most people won’t even pay attention to the water aspect. Sadly, this is a huge mistake, but people will then automatically turn to the coffee or something else as the source of the problem when that may not be the case. 

But the way I see it, you have two main options: tap water or bottled water. So, I will start to explore both options to see which one is best.

Using Tap Water for Coffee

tap water in pitcher for making coffee

Most people will have no problem with using tap water to make coffee. It’s undoubtedly the most common choice, and it’s literally on tap.

But to get to the bottom of which water option is best, you need to think about the minerals contained within your coffee. This is crucial as those minerals will change the taste of the water, and as a result, it can change the taste of your coffee.

Soft Water is the Best

What I’ve found is that soft tap water is best for coffee. Soft tap water means it’s lower in those minerals, and that’s actually a good thing.

What happens with soft tap water is it doesn’t get the opportunity to really interfere with the taste of the coffee beans. It lacks the intensity that comes with the minerals, but it also does something else: potentially affecting your coffee machine.

Limescale Build-Up and Your Coffee Machine

When you have hard tap water, it means you will need to descale your coffee machine as limescale builds and will eventually cause problems. Also, limescale will change the taste of everything, and that’s not what you want to happen. 

But the potential for limescale to damage your coffee machine is the most concerning thing of all. 

Yet, there’s a key point to mention here. You don’t want all the impurities removed, and soft water should certainly not be like that.

Instead, it should still contain some calcium and magnesium, and these are both crucial elements that help bring coffee to life.

How Calcium and Magnesium Help Coffee

Calcium is the element that prevents water from becoming too soft, so it’s required in your water. However, it’s magnesium that plays a more critical role in your coffee.

What tends to happen, and this is something I only recently discovered, is that magnesium effectively sticks to the coffee compounds. As a result, it helps the coffee to deliver a smoother taste, and it does this without taking anything away from the flavor.

Using Bottled Water for Coffee

using bottled water for making coffee

The first thing that stands out regarding bottled water is you won’t have the same issue regarding hard water. That means you don’t need to stress about limescale or anything else, and that’s a fantastic thing.

Bottled water is clean and with no impurities; it does mean the flavor of the coffee beans will come to the fore. I do love this idea, and I can see why people living in an area with hard tap water could feel drawn to using bottled water.

The Problem With Bottled Water

I’ll be honest with you, I understand that using water that allows the coffee flavor to come to the fore is a good thing. Still, bottled water is not always a positive when it comes to your coffee.

Instead, it does have several problems.

Sometimes, the problem is more to do with the process the water goes through. It’s almost as if the water is over-processed, removing all traces of anything from the water.

While you may think this is a great thing. It’s not.

Instead, removing too many of the impurities gives the coffee nothing to work with, and it could lead to a coffee that is too dull. You need some of that calcium and magnesium in water to help bring it to life.

If you don’t expect your coffee to be pretty weak.

And there’s another problem with bottled water. The cost.

It can quickly become quite expensive over a week if you drink a lot of coffee. That’s certainly something you need to think about when it comes to determining if bottled water is something you want to use.

What is the Best Water for Coffee?

I personally use tap water for my coffee. Still, I admit this idea of looking into tap water and bottled water did give me one or two things to think about. Ultimately, it led me to think: what is the best water for coffee?

Now, by that question, I don’t mean a particular brand of bottled water or tap water from a specific part of the world. Nope, what I am wondering is what should be contained in the water to then get the perfect cup of coffee?

Well, this is what I discovered.

Hardness Rating

If you view water on a sliding scale, from soft water on one end to hard water on the other. When you do that, the ideal water for coffee should be sitting somewhere on the soft side but not at the extreme end.

That’s because water needs some hardness, and extremely soft water is too limp for coffee.

No Chlorine

Another key component is you don’t want any chlorine in your water. That’s just a bad idea, and it’s something that often pushes people toward bottled water.

But the reality is most tap water will contain no chlorine, so there’s no real need to automatically presume bottled water is best.

pH Rating

From a pH perspective, water is clearly neutral, but even with this, it’s on a sliding scale. But it’s best if your water is as close to a pH of 7.0 as possible. 

I’m not saying water slightly on either side of that 7.0 will be disgusting. However, the closer it is to that figure, the better your coffee will be, as there’s nothing to then taint it. 

Which Option Would I Choose?

I need to take my tap water out of the equation to answer this. I live in an area where it’s soft water and pretty pure, so I don’t need to think about hardness rating, chlorine, or anything else.

But that does mean my answer should be obvious to most in that I would always try to choose tap water, and I’ll give you my reasons as to why.

If the tap water has the correct balance from a softness and pH perspective, why would you go to a store, buy bottled water, and then use that? It doesn’t make sense to me.

And yet, I understand why people may feel the need to head down the bottled water road. There’s nothing worse than failing to achieve a decent cup of coffee, and it’s depressing when the source of the issue is something so basic as water.

But if you have a water filter built into your system, then I would still stick to tap water as much as possible. I just feel it’s the better option, and you don’t then have to contend with the plastic from the bottles either.

Also, as long as you don’t have the limescale issue, I doubt you have much to worry about. In addition, there’s less need to worry about descaling either. 

My Recap on Using Tap Water or Bottled Water for Coffee

Either tap water or bottled water can be used to make coffee, but I just want to give a recap on the key points you need to look out for when making your decision.

  • If your tap water is slightly soft, it’s perfect for coffee
  • If you have hard water, use bottled or filter it
  • Hard water contains limescale, and it changes the taste
  • Hard water will also damage your coffee machine
  • If the water is too soft, your coffee will taste flat
  • Bottled water can sometimes be too pure for a good coffee

Overall, it’s best to know your local water and see if it’s something you can work with. Often, it will be the most balanced option out there. 

My Conclusion

If I had to choose, I’d always opt for tap water if it’s not too hard and full of impurities. I feel bottled water can work, but you do run the real risk of it producing a dull coffee.

But if you have hard water, then it could make your coffee taste horrible. Basically, you need to understand your natural water supply and whether you can drink it without any problems before deciding.

But don’t really filter your water, as that will also remove impurities to such an extent that you could cause problems for your coffee.