Baking soda removes mineral buildup and stale coffee oils without harsh chemicals
Baking soda is one of the safest and most effective ways to clean the inside of your coffee maker. It dissolves mineral deposits left by hard water, cuts through old coffee oils that can turn fresh coffee bitter, and costs just a few cents. Unlike commercial descaling products, baking soda leaves no chemical taste and is safe if a small amount remains in the machine.
The process takes about 30 minutes of active work spread across two brew cycles, plus time for soaking. You do not need to take the machine apart, and the method works on drip coffee makers, percolators, and most automatic machines.
Key Takeaways
- Mix one-quarter cup of baking soda with one cup of water to create a cleaning solution that dissolves mineral buildup without damaging your machine.
- Run the baking soda solution through a full brew cycle, then run plain water through two more cycles to rinse completely.
- For heavy mineral deposits, fill the water reservoir with plain water mixed with baking soda and let it sit for 15 to 20 minutes before brewing.
- Clean your coffee maker with baking soda once a month if you have hard water, or every two months for soft water.
- Never mix baking soda with vinegar in your coffee maker, because the fizzing reaction can damage internal parts.
What you need before you start
Gather baking soda, water, a measuring cup, and a spoon. You do not need a brush or cloth for the inside of the machine—the baking soda solution does the work. Have a sink or large bowl ready to catch water that drains from the machine during cleaning.
Check that your coffee maker is unplugged and completely cool. If you just brewed coffee, wait at least 10 minutes. Make sure the carafe is empty and the filter basket is empty of grounds and old filters.
The basic cleaning method for most coffee makers
Fill the water reservoir with one cup of water and stir in one-quarter cup of baking soda until it dissolves. The mixture should look like cloudy water with no visible powder. If you see grit at the bottom, stir longer or add a few more drops of water.
Place an empty carafe under the brew basket and turn the machine on. Let the full cycle run without stopping. The baking soda solution will flow through the heating element, spray head, and brew basket—the places where mineral buildup hides. This takes 5 to 10 minutes depending on your machine.
When the cycle finishes, empty the carafe and refill the reservoir with plain water only. Run a full brew cycle with plain water. Repeat this rinse cycle one more time. You are washing out the baking soda and any loosened mineral particles. If you smell baking soda after the second rinse, run a third cycle.
Deep cleaning for heavy mineral deposits
If your coffee maker brews slowly, sputters, or has not been cleaned in several months, the heating element likely has thick mineral buildup. For this situation, let the baking soda solution soak inside the machine before brewing.
Mix one-quarter cup of baking soda with one cup of water in the reservoir. Do not turn the machine on yet. Let it sit for 15 to 20 minutes. The baking soda will soften stubborn deposits. Then run a full brew cycle as described above, followed by two plain-water rinse cycles.
If the machine still brews slowly after this treatment, the buildup may be too heavy for baking soda alone. In that case, you can repeat the soak-and-brew method a second time, waiting a full day between treatments to avoid stressing the heating element.
Cleaning the carafe and brew basket
While the machine runs its cycles, clean the carafe and brew basket by hand. Fill the carafe halfway with warm water and add one tablespoon of baking soda. Swirl it around for 30 seconds to loosen stains and old coffee residue on the glass. Rinse with plain water.
For the brew basket, rinse it under warm running water and scrub the underside with a soft cloth or sponge dampened with baking soda paste. Make a paste by mixing one tablespoon of baking soda with just enough water to make a thick slurry. This removes the brown film that builds up where water sprays onto the grounds. Rinse thoroughly so no baking soda powder remains.
Common mistakes that damage the machine
Do not use vinegar and baking soda together in your coffee maker. When these two mix, they fizz and bubble violently. This reaction can force liquid into parts of the machine not designed to handle it, potentially damaging the heating element or electrical connections. If you want to use vinegar, do that in a separate cleaning session at least one week apart.
Do not use more than one-quarter cup of baking soda per cup of water. Too much baking soda can leave a white powder coating inside the machine that is hard to rinse out completely. Stick to the ratio given above.
Do not scrub the inside heating chamber or spray head with a brush or cloth. You cannot reach these parts safely without taking the machine apart, and brushing can scratch the metal. The baking soda solution does the cleaning—you do not need to scrub.
How often to clean and what to watch for
If you have hard water (water that leaves white spots on dishes), clean your coffee maker with baking soda once a month. If you have soft water, every two months is enough. You can tell it is time to clean when the machine brews noticeably slower than it did when new, or when fresh coffee tastes flat or bitter even with fresh grounds.
Between baking soda cleanings, rinse the carafe and brew basket after each use and empty the water reservoir if you will not use the machine for more than a day. This prevents stale water and old grounds from sitting inside, which speeds up buildup.
Frequently Asked Questions
Can I use baking soda in the water reservoir while making coffee to drink?
No. Baking soda is for cleaning only. Always run the baking soda solution through an empty machine with no coffee grounds, then rinse with plain water before you brew coffee to drink. Even a small amount of baking soda left in the machine will make your coffee taste salty and unpleasant.
What if my coffee maker has a built-in water filter?
Remove the filter before running the baking soda cycle. Baking soda can clog the filter or reduce how well it works. Rinse the filter under plain water and set it aside. After you finish the baking soda cleaning and plain-water rinses, put a fresh filter in before you brew coffee to drink.
Is baking soda safe for machines with plastic parts?
Yes. Baking soda is gentler on plastic than vinegar or commercial descaling products. It will not crack or discolor plastic water reservoirs or brew baskets. Just make sure the baking soda dissolves completely in water before it enters the machine—undissolved powder can scratch plastic surfaces.
How do I know if I rinsed enough?
Smell the carafe after the second plain-water rinse. If you detect a salty or alkaline smell, run one more plain-water cycle. You can also brew a small cup of water with no grounds—if it tastes salty, rinse again. Once the brewed water tastes neutral, you are done.
Can I clean a coffee maker that has not been used in months?
Yes, and you should. Old water left in the reservoir can grow mold or bacteria. Empty any old water, then run the baking soda cleaning method. Use the deep-cleaning soak method (15 to 20 minutes) because mineral and mold buildup will be heavy. After the baking soda cycle and rinses, brew one cup of plain water and discard it before making coffee to drink.