How to Clean Your Espresso Machine, According to an Expert

Keeping your espresso machine clean is wicked important. Coffee oils stick to metal surfaces and grow rancid over time, imparting musty, bitter flavors. Plus, coffee residue and scale build-up can block water lines, and unclogging them is expensive.

Regular cleaning helps prevent icky espresso and also keeps your machine running smoothly. The simplest way to clean it is to backflush; that is, run coffee detergent through the machine with a blank portafilter basket.

Before diving in, I recommend checking that your machine can be backflushed. Cheaper espresso machines don’t always have this ability. Once you’ve double-checked the user manual, though, you can follow my cleaning guide below. 

Espresso Machine Cleaning and Maintenance Tools

A Multi-Use Coffee Tool

Pallo Coffee Tool

$16 at Amazon View on Seattlecoffeegear.com

This brush has stiff nylon bristles for scrubbing the group head clean after you pull an espresso shot. It also has a scoop for measuring out coffee detergent powder and a thin metal rod for cleaning a steam wand’s holes. 

The Best Coffee Detergent for Espresso Machines

Urnex Cafiza Espresso Machine Cleaning Tablets

$36 at Amazon

Designed to break up coffee oils, Cafiza is the standard espresso machine detergent used in most commercial espresso bars. While it also comes in a loose powder form, these tablets are convenient and less messy. 

Dark Colored Microfiber Cloths

Microfiber Wholesale Buff Pro Multi-Surface Microfiber Cleaning Cloths

$16 at Amazon

Microfiber cloths are great for polishing the outside of your espresso machine, and most any will do. I usually buy dark-colored ones so they don’t show coffee stains. 

A Double-Sided Screwdriver

K20 Tools Short Stubby Screwdriver

$14 at Amazon

You’ll need to remove the group head screen to make sure everything is thoroughly cleaned, and this short screwdriver will do so painlessly. It has both a flat and Phillips-head while being small enough to fit between the drip tray and group head. 

How to Blackflush an Espresso Machine

Step 1: Scrub the Group Screen with a Brush

The first thing you’ll want to do is to grab your group head brush and scrub the screen and rubber gasket clean of any coffee residue or leftover coffee grounds. It also helps to run the espresso machine to flush the group head with clean water.

Step 2: Remove the Group Screen

Using a stubby screwdriver, unscrew the group head screen and place it in a heat-proof container. Place the screen in a shot glass or other small vessel so it won’t get lost. 

Step 3: Remove the Filter Basket

Pop the filter basket out by leveraging the screwdriver against the short metal wings of the portafilter. Place the filter basket in the heatproof container with the screen. Note: If your machine comes with a rubber backflush disk instead of a blank metal portafilter basket, you can skip this step. 

Step 4: Backflush

Insert the blank basket (the one with no holes) into the portafilter and add a Cafiza tablet or a half teaspoon of coffee detergent powder. If you have a rubber backflush disk instead of a blank metal portafilter basket, place the rubber disk over the holes in your regular filter basket so that it forms a seal.

Lock the portafilter into the espresso machine and run the group head for five seconds. This will pressurize the hot water and Cafiza mixture into the espresso machine. Press the group head button again to stop the machine and allow the water to be expelled into the drip tray. Repeat three more cycles of five seconds on and five seconds off to fully flush any residual coffee detergent from the machine.

Step 5: Soak

Once the machine is backflushed, add the portafilter into the heat-proof container with the handle sticking up. Add one Cafiza tablet or a half teaspoon of coffee detergent to the container, and pour in enough boiling water to cover all of the metal surfaces. Let soak for 20 minutes.

Step 6: Rinse and Reassemble

After everything has soaked for 20 minutes, dump the cleaning solution into the sink and rinse off everything. Reassemble the screen and reinsert the basket into the portafilter. After inserting the portafilter back into the espresso machine, flush the group head for 10 seconds through the filter basket to ensure no detergent residue remains.

Step 7: Empty and Clean the Drip Tray

While this is unrelated to back-flushing your machine, cleaning out the drip tray is an important task that's easy enough to do. Some espresso machines, like most Brevilles, even have pop-ups that indicate when the tray is full. To clean it, carefully detach the drip tray (you don't want to spill dirty water everywhere! More mess to tackle!), empty it into the sink, and gently clean the parts with a sponge and soap before rinsing and drying. Put it back and voila, your espresso machine is ready to pull a shot.

A Quick Note About Coffee Detergents

Coffee detergent powders are made from a variety of salts and acids and can cause skin irritation. Be sure to thoroughly rinse any part of the espresso machine you clean with coffee detergent and wash your hands with warm, soapy water afterward. You can also wear cleaning gloves if you’re concerned about exposure. 

FAQs

What can I run through my espresso machine to clean it? 

The only substance you should use to clean your espresso machine is an espresso machine-specific coffee detergent, like Urnex Cafiza Tablets. These cleaners are formulated to break down coffee oils but also to dissolve easily in water so that they won’t create any build-up inside of the machine. 

Is it okay to descale my espresso machine with vinegar? 

No—vinegar has strong odors and flavors that can affect both the life of your espresso machine and the flavor of every shot you pull. Descaling an espresso machine be a harsh process, so it’s better to use softened and filtered water, or a product like Third Wave Water, to prevent scale build-up in the first place. 

How often should an espresso machine be cleaned?

Espresso machines should be scrubbed clean with a brush every time you use them, but backflushing only needs to be done around once a week or so. A good rule of thumb is to backflush whenever possible because it assists with preventing scale build-up, even if you only pull one shot of espresso a day. 

What happens if you don't descale your espresso machine?

Coffee scale buildup can not only make your espresso shots and drinks taste burnt and bitter but also harm your fancy-schmancy espresso machine. If you let scale build up, it can gunk up your machine, preventing water from flowing through it. Some brands let you send the machine in to be cleaned up, but this can cost a couple hundred dollars. Save yourself the hassle (and a trip to the post office, not to mention a few weeks without espresso) and buy a few Urnex Cafiza Tablets and backflush your machine.

Why We’re the Experts

• Jesse Raub was Serious Eats' commerce writer and spent over 15 years working in the specialty coffee industry. He was our in-house coffee expert and regularly tested coffee gear for this site. 
• He has cleaned and backflushed over 300 espresso machines in his career in the coffee industry, and regularly cleans his personal espresso machine at home, too.