Does Decaf Coffee Dehydrate You? 

If you’ve ever reached for a cup of decaf and wondered, “does decaf coffee dehydrate you?” you’re not alone.  After all, is it the coffee or the caffeine that is rumored to cause dehydration?

At Philly Fair Trade Roasters, we believe good coffee should add to your day—not work against you.  That’s why we look to source quality Organic, Fairtrade coffee processed in an Organic facility.  Ethically sourced, expertly roasted.   

So, let’s clear the air (and fill your mug): decaf coffee does not dehydrate you. Below, we’ll explain why that myth exists, what science actually says, and how high‑quality Organic, Fairtrade decaf fits into a healthy daily routine.

PS - if all this talk about decaf makes you thirsty, check out our Decaf Peru for a darker roast, or our Decaf Mexico for a medium style decaf.  A perfect companion for that quiet evening book read or after dinner coffee.  Especially if you plan on sleeping.

Where the Myth Started: Is Coffee Dehydrating?

The idea that coffee dehydrates you comes from caffeine’s reputation as a diuretic.  A diuretics increases urine output, which can lead to a net negative fluid loss in certain situations.  Caffeine is a diuretic, but not all diuretics are caffeine.

 And it’s a well-earned reputation as a diuretic, because its true.  It’s the reason we contemplate (or is it just me?) the second cup of coffee before a long drive. 

But here’s the breakdown with assuming coffee causes dehydration -

• Coffee isn’t just caffeine
• Most people build tolerance to caffeine, which also means it causes less fluid loss (in other words, the more we get used to coffee, the less it causes us to go to the bathroom).
• The fluid content of coffee offsets caffeine’s mild diuretic effect. 

When the topic is decaf coffee, things change even more!

What Is Decaf Coffee, Really?

Spoiler – decaf coffee is not caffeine free.  It’s coffee that has had 97–99% of its caffeine removed before roasting.

A typical 8‑ounce cup of coffee has:

• 2–7 mg of caffeine in decaf
• 80–120 mg of caffeine in regular coffee

That small amount of caffeine matters when we’re talking about hydration.

At Philly Fair Trade Roasters, we prioritize chemical‑free decaffeination methods, like Swiss Water® or Mountain Water Process, which remove caffeine using water, temperature, and filtration—not harsh chemicals. The result is cleaner coffee and peace of mind.  Plus, we think it tastes pretty great too!

Does Decaf Coffee Dehydrate You?

Let’s answer the question directly:

No—decaf coffee does not dehydrate you.

Remember our friend caffeine?  Of course, we all do!  Since decaf doesn’t have a large enough amount of caffeine to cause a meaningful diuretic effect (it doesn’t have enough caffeine to make us go to the bathroom).  Quite the opposite in fact, decaf coffee can actually contribute to daily fluid intake, much like herbal tea does. 

Research consistently shows that:

• Habitual coffee drinkers do not experience net fluid loss from coffee
• Low‑caffeine beverages behave like water in the body
• The liquid in coffee offsets any minor diuretic action

In plain terms: decaf coffee is net hydrating, not dehydrating.

How Hydration Actually Works

Hydration isn’t about avoiding every beverage except water. It’s about overall fluid balance throughout the day.  Like a bank account, our hydration is about our withdraws and deposits. 

True dehydration usually comes from:

• Prolonged sweating without fluid replacement (include a few electrolytes when replacing since you sweat more than just water)
• Intense exercise or heat exposure
• Illness (vomiting, diarrhea)
• Excessive alcohol consumption

A cup of decaf coffee doesn’t come close to causing dehydration under normal circumstances. If anything, replacing sugary drinks with decaf coffee can support better hydration habits.  A simple swap for a positive upgrade to your health. 

Did we mention we think our decaf tastes pretty great too?

 Decaf vs Regular Coffee: A Hydration Comparison

Regular Coffee

• Moderate to high caffeine (usually 80-120 mg of caffeine per 8 oz)
• Mild diuretic effect in people not used to drinking coffee
• Generally hydrating for habitual coffee drinkers

Decaf Coffee

• Minimal caffeine (2-7 mg of caffeine per 8 oz)
• No meaningful diuretic effect
• Counts toward daily fluid intake

For people sensitive to caffeine—or those who enjoy coffee later in the day—decaf is an easy win.

Does Decaf Coffee Count as Water Intake?

Yes. Decaf coffee counts toward your daily hydration.

While plain water should still make up the foundation of your hydration strategy, beverages like decaf coffee and herbal tea absolutely contribute to fluid intake.

Why Organic, Fairtrade Decaf Matters

Not all decaf coffee is created equally, we’re talking about Swiss Water & Mountain Water Process vs conventional decaf. 

Many conventional decaf coffees are processed using harsh chemical solvents, which of course may end up in your coffee. 

At Philly Fair Trade Roasters, we take a different approach.

Using water‑processed decaf methods, Swiss Water and Mountain Water as mentioned above, remove caffeine gently while preserving the natural character of the bean.  Learn more about Swiss Water & Mountain Water process here.

Like choosing Organic coffee, Swiss or Mountain Water Process Decaf rather than conventional, is a small change that compounds over time for those who make drinking decaf a habit.  A habit we encourage!

Can You Drink Decaf Coffee All Day?

For most people, yes.

Because decaf has minimal caffeine, it’s well tolerated throughout the day, even in the afternoon or evening. It’s a great way to add some of that warm coffee taste to your day without too much caffeine. 

From a hydration standpoint, there’s no reason to limit decaf beyond what feels comfortable for your body.

What About Electrolytes?

Decaf coffee does not meaningfully deplete electrolytes.  Nor does it provide meaningful electrolytes either. 

If you’re very active, sweat heavily, or follow a low‑carbohydrate diet, electrolyte balance is something to be mindful of—but that’s independent of decaf coffee consumption.

For most people, normal meals and adequate fluid intake are more than sufficient.

Common Myths About Decaf Coffee

Myth: Decaf is completely caffeine‑free
Truth: It has trace amounts—far too little to dehydrate you.

Myth: Decaf tastes weak
Truth: High‑quality, well‑roasted decaf can be just as flavorful as regular coffee.

Myth: Decaf isn’t “real” coffee
Truth: It’s the same coffee—grown, harvested, and roasted—just with most of the caffeine removed.

Final Sips: Does Decaf Coffee Dehydrate You?

No—decaf coffee does not dehydrate you.

When brewed from high‑quality beans and processed cleanly, decaf coffee is a flavorful, hydrating part of a healthy lifestyle.

At Philly Fair Trade Roasters, we believe coffee should support your well‑being and the people who grow it. If you love coffee but want less caffeine—and no hydration worries—Organic, Fairtrade decaf is a choice you can feel good about.

Just one more way we’re helping you have a good day!

So whether you're ready to fuel up your good day with a cup of Organic, regular coffee, wind down a good day with a cup of decaf or haven't made up your mind yet (may we suggest some half caf?) we've got you covered right here!

PS - find something you like? Right now subscriptions are 25% off the first order, then 5% off each order after that.  Just find your favorite beans and choose your plan!