The Keurig B31/K10 Mini Plus Brewing System is a compact single cup coffee maker for home use. Choose between 6, 8 or 10 ounces of coffee per cup.
The Mini Plus uses the more expensive K-Cups instead of ground coffee, making it easy to set up, clean and produce consistently good coffee. However, you can brew your favorite ground coffee too by using the My K-Cup reusable coffee filter (not included).
To keep it looking and performing at its best, be sure to clean the outside and internal components regularly.
This machine is UL listed for Household Use Only. If you’re looking for a similar single cup coffee maker for the office, you may be interested in our review of its commercial counterpart, the B130 DeskPro.
Also, visit our comparisons of all commercial and household Keurigs, as well as our review of the new Keurig 2.0 (both links open new windows).
Do You Already Own a Mini Plus?
Keurig has recalled Mini Plus brewers (K10/B10/B31 ) produced prior to July 2014 due to a possible burn hazard from spraying hot water. Learn how to identify if your brewer is involved and how to receive a free repair kit. Meanwhile, Keurig recommends not brewing more than 2 cups in rapid succession and to maintain an arm’s length distance from the brewer during the brewing process.
In a Hurry?
Skip to our conclusions about the Mini Plus.
Description of the Mini Plus
Keurig has recently changed the name of its B31 Mini Plus to K10 Mini Plus, but the B31 and K10 are the exact same machines. A third machine, the B30 Mini, is an older model that was a little more difficult to operate. It is no longer being manufactured. This review is for the Keurig K10 (B31) Mini Plus.
The Keurig Mini Plus is a popular personal coffee maker that brews a cup of coffee in about two minutes. It accomplishes this by forcing hot pressurized water through pre-packaged K-Cups, extracting the flavors much more quickly than a drip brewer would. Since all of the brewing taking place within the disposable K-Cup, this brewing system is easy to set up and tidy, making for no-fuss cleanup. If you prefer to use your favorite brand of ground coffee, the My K-Cup reusable filter (sold separately) gives you the flexibility to do so.
The single-use water reservoir holds enough for one 6, 8 or 10-ounce cup of coffee or tea. It does not store hot water to make subsequent cups more quickly, so each time you want a cup of coffee you’ll need to add water and start over from scratch. Simply repeat the full brewing process for each cup of coffee.
This single serve coffee maker is easy to use, with LED lights to indicate what step of the setup and brew cycle the machine is on. There is a compartment on the back of the machine for storing the short power cord when not in use (you need to push it into place, as it’s not retractable). Its compact size and portability makes it ideal for small spaces like home offices, apartments, RVs, vacation homes and some dorms (check ahead for UL listing requirements). It is available in several gorgeous colors.
It’s important to clean your new Keurig Mini Plus brewer before making your first cup of coffee. Simply follow the instructions for brewing a cup of coffee but omit the K-Cup and discard the resulting cup of hot water.
To make a cup of coffee, make sure the coffee maker is plugged in and then press the “Power” button. Lift the lid for the water reservoir and pour in the desired amount of water and close the lid (pre-measured 6, 8 or 10 ounces – or pour until the water reaches the rim of your desired fill level). Lift the handle to expose the brew basket. Water will begin to drain into the brewer.
Meanwhile, place a cup or mug of the correct size on the drip tray (the drip tray is for catching spills but can be removed to accommodate a taller mug). Insert a K-Cup (do not remove or puncture the foil lid) and wait for the water to finish draining before you lower the handle (about 5 seconds).
Press the flashing “Brew” button, which will flash red while the water is heating (about 2 minutes) and will turn solid red once your coffee starts to dispense. Remove the used K-Cup and power the machine off once it has finished brewing. Or let it power itself off, which it will do automatically after 90 seconds of inactivity. Repeat the full process to brew subsequent cups. Empty the drip tray whenever the red overflow indicator pops up.
Type of Coffee Used
K-Cups. 200+ flavors of coffee and other beverages are available.
You can brew your favorite ground coffee using the My K-Cup reusable filter, which is sold separately.
Type of Coffee Produced
K-Cups are available in a wide assortment of roasts, flavors and blends.
For strong coffee, select an extra bold K-Cup (with up to 30% more ground coffee) and use a smaller amount of water. The less water you use, the stronger the coffee.
More Than Just Coffee
The Mini Keurig can produce hot water for tea and other uses, and K-Cups are available for many hot beverages besides coffee. Iced beverages can also be made with this machine.
No coffee or water filters are required for this machine, but the reusable My K-Cup filter for ground coffee can be purchased separately.
Filtered or bottled water is recommended, especially if your coffee tastes of undesirable substances like chlorine.
While K-Cups are more expensive than ground coffee, the mess-free convenience is worth it to many users. Ground coffee can also be brewed in this machine with the reusable My K-Cup filter.
Amount of Coffee Per Serving
The Keurig Mini Plus brewer gives you the choice of brewing 6, 8 or 10 ounces of coffee per serving. A minimum of 6 ounces of water is required for the brewer to work properly. Remove the drip tray to brew into a taller mug. However, keep in mind that without the drip tray to catch spills you need to be careful to not overfill the machine or to spill water when filling it. The machine accommodates a mug that is 4.5” tall or less with the drip tray, and up to 5.5” tall without the drip tray.
It takes about 2 minutes to brew each cup of coffee.
This machine operates via manual push-buttons. LED lights indicate which step of the set-up and brewing process the machine is on.
The Mini Keurig brewer will automatically shut off at any stage of the brewing process if it’s idle for more than 90 seconds, like if you wait too long to activate the brew cycle. Press the “Power” button to restart it. If the “Brew” button was flashing blue when the brewer shuts off, lift and lower the handle to restart it.
Keurig K10 Mini Plus Cleaning and Ongoing Maintenance
After you’re finished brewing, remove the K-Cup and wipe down the outside of the coffee machine with a soft damp non-abrasive cloth.
Water remaining in the water reservoir can be emptied by holding down the “Brew” button until all of the water has dispensed into a cup. Make sure the water reservoir lid is down before doing so.
Inspect the Drip Tray periodically and wipe it down with a damp soft non-abrasive cloth. When the Drip Tray Overfill Indicator appears, empty the drip tray and pour the contents into a sink. Carefully slide the tray toward you to remove it. Do not put the Drip Tray or Drip Tray Plate into the dishwasher.
The K-Cup Assembly (Funnel and K-Cup Holder with Exit Needle) can be removed and washed on a low temperature cycle in the top shelf of the dishwasher. The Exit Needle can be cleared of coffee grounds with a straightened paper clip.
Clean the water reservoir as needed by removing the Water Level Guide and wiping down the inside of the reservoir with a clean non-abrasive damp cloth. The Water Level Guide is not dishwasher safe.
Descale regularly (every 3 – 6 months, possibly more if using hard water) with Keurig Descaling Solution or white vinegar, following the included instructions.
If the Mini coffee maker is not producing full cups of coffee (not all of the water is flowing through), clean the exit needle (remove all coffee grounds), the K-Cup Assembly and follow with a descaling. If no water is coming out at all, or these steps still don’t produce full cups, clean the entrance needle also. Make sure all three holes in it are free of grounds (the following video only mentions two holes).
Store the coffee maker upright in a frost-free place, otherwise freezing condensation might damage the machine. Make sure the internal Hot Water Tank and Water Reservoir are empty. If it has been stored in a cool place, allow the machine to rest at room temperature for two hours before turning it on. After storage, run 3 cleansing brews without K-Cups before using the brewer.
This machine has a one-year warranty against defects under normal home use.
The manufacturer can be reached by phone 7 days a week and any time by email, although the seller handles refunds and replacements.
Replacement drip trays and K-Cup holders are available, but call the manufacturer’s help line first, as they may offer another solution. Keep in mind that the warranty will be voided if you open up the machine to try to diagnose a problem or fix it yourself.
Keurig K10 Mini Plus Features
- Single cup personal brewer
- Choice of 3 cup sizes – 6 oz., 8 oz. and 10 ounces
- 13 colors to choose from
- Single-use water reservoir
- Energy Savings Mode – shuts itself off automatically after 90 seconds of inactivity
- Removable drip tray with Overfill Indicator
- UL rated for Household Use Only
What’s in the Box
Coffee maker, Owner’s Manual, Quick-Start Guide and a small K-Cup variety pack.
Unit size: 10.8″H x 10.7″D x 6.9″W.
Overall height when the water tank lid is open is 12.5”.
Weighs 8.75 pounds.
Cord: 15.5” long (not counting the plug itself) with a three-pronged plug.
The Keurig Mini coffee maker accommodates a mug that is 4.5” tall with the drip tray in place, and one up to 5.5” tall without the drip tray.
UL Listed for Household Use Only. Not appropriate for office buildings and other commercial environments. Learn more about UL listings.
- 1,425 watts
- Voltage: 120VAC / 60 Hz
- The Mini Plus saves energy by automatically shutting off when it’s inactive for 90 seconds, whether that’s during the setup and brewing process or after it’s finished producing a cup of coffee.
- A solid, basic single serve coffee maker that’s easy to operate.
- Its small size makes it great for small kitchens, dorm rooms, RVs, home offices, and for taking on the road.
- K-Cups make it largely mess-free and easy to keep clean.
- Each cup of coffee can be a different flavor – just use a different K-Cup.
- Can be used to make coffee and tea in a variety of flavors, as well as other hot and iced beverages.
- The My K-Cup reusable coffee filter is available for brewing your favorite ground coffee.
- Choose between making 6, 8 or 10 ounces of coffee or tea.
- There’s no need to use special water, although filtered or bottled water is recommended, and hard, softened, distilled and reverse osmosis water is discouraged.
- No filters to deal with.
- Economizes on electricity usage.
- Produces hot coffee.
- The coffee has good flavor.
- Many colors to choose from.
- Produces a limited amount of coffee per cup – 6, 8 or 10 ounces.
- Does not have a reservoir with hot water, therefore the brewer must heat and brew each cup of coffee separately.
- Does not accommodate the height of standard travel mugs.
- The setup process requires an exact sequence, which may confuse some users until they get the hang of it.
- Needs regular cleaning of exterior and internal parts to perform well.
- No auto-start feature so you can’t schedule it to begin brewing at a certain time, like first thing in the morning.
- UL listed for Household use only – not intended for use at the office or in other commercial environments (a plus if you’re looking for a machine for home use).
Tips from Users
- Run a cup of white vinegar through the machine (without installing a K-Cup) to remove any lingering plastic taste and smell. Follow that up with several brews without a K-Cup to rinse out all of the vinegar.
- If you want more than 10 ounces of coffee, brew a 6 oz. cup. Refill the reservoir after the first brewing and run it again using the same K-Cup with another 6 ounces of water. Empty the first cup of coffee into a large mug (or travel mug) before using that cup again for the second brewing – then pour the second cup of coffee into the larger mug, as well.
- To avoid spilling water, some users recommend filling a measuring cup with a pour-lip with the correct amount of water and pouring that into the machine. Be especially careful not to spill water if you’re using the machine without the drip tray.
- An easy way to measure out the right amount of water is to fill the cup you’ll be brewing into and pour that into the reservoir.
- Avoid clogged needles by removing the K-Cup immediately after brewing.
- Be aware of the top needle. Its three holes need to be kept free of coffee grounds in order for the water to flow smoothly (not mentioned in the Users Manual cleaning instructions).
- Users report having good results using reusable filters from Cafe Cup, Solofill, Melitta Java Jig and EkoBrew instead of My K-Cup.
- You may need to experiment to achieve the brew you want when using ground coffee. Some user reviews say that their usual store-bought ground coffee produces weak coffee in the Keurig Mini brewer, while others say their favorite ground coffee is too strong. Adjust the amount of coffee used, the grind, and the amount of water to suit your tastes. Some say to use twice the amount of ground coffee as you would in a drip maker. Others suggest that grinding your own beans improves the flavor over store-bought grinds. You may need to experiment to find the right coarseness. Grinding your own coffee beans rather than using finely pre-ground coffee for drip brewers can also eliminate silt in the bottom of the cup.
Keurig K10 Mini Plus Brewer Consumer Reviews
The Keurig B31 (K10) Mini Plus single cup coffee maker is a bestseller on Amazon.com. At the time this is written it is highly rated with 706 reviews.
The majority of users report that this coffee maker produces excellent coffee, and they appreciate its ease of use, small size and all of the coffee, tea and other beverage choices available in K-Cups (200+ to choose from).
A few users report that their machine stopped working shortly after purchasing it. In some cases it’s unclear to us if this is due to user error or machine defects, but clogged needles seem to often be the cause. Keurig Support is attentive and dedicated to helping to solve any problems, and will quickly send a replacement machine if that is required. They stress that it’s important to keep the needles clean and the machine descaled.
A common complaint is that this coffee maker can begin to produce partial cups of coffee (not all of the water flows through). Cleaning the exit needle and/or descaling usually fixes this. If not, or if no water flows through at all, you may need to clean the entrance needle as well, removing all coffee particles from all three holes in it. Users also suggest gently pushing the K-Cup down onto the lower needle to release internal air pressure before closing the lid, as this prevents trapped air from puffing grounds up into the entrance needle.
Another complaint is that some users experience leakage from the bottom of the machine. This is often due to an overfull drip tray or clogged needles that prevent the water from draining the way it should. It may also be due to not waiting for the water in the reservoir to drain into the heating unit before closing the handle. Also, be sure to not use more than 10 ounces of water. Fill your mug with water first, and use that as the measurement. In rare cases the machine may be defective. Keurig will replace it as long as the warranty is in effect.
Some users report that the coffee this machine produces is not very hot (drinkable without having to wait for it to cool), while others say the coffee is too hot to drink right away. Some even recommend putting the cup of coffee in the microwave for a few seconds so it’s hot enough. The manufacturer says that the coffee is brewed at 192 degrees, so it comes out of the machine very hot. However, the temperature of the cup, as well as cold creamer can lower the coffee temperature. They recommend pre-warming the cup by filling it with hot water and letting it sit for a minute before emptying it and placing it on the drip tray for brewing (or rinse it under hot water for a minute or two). They also recommend placing the cream in the bottom of the cup before brewing, rather than pouring it into the hot coffee.
User reviews suggest that using chilled water can cause problems with the machine and recommend using room temperature water. The manufacturer agrees, saying that chilled water may not reach a high enough temperature to allow the machine to brew properly or the coffee may not be as hot as it could be.
Some users feel that this machine is not as sturdy as more expensive models and are disappointed by that, while others feel it’s quite sturdy for home use.
The K10 Mini Plus makes some noise while brewing, but users feel it’s not enough to wake a baby sleeping in the next room.
It’s reported that this machine does not emit excessive steam, and therefore can be used under an upper cabinet.
The user guide contains this alarming statement: “WARNING – this product contains chemicals, including lead, which is known to the State of California to cause cancer, birth defects or other reproductive harm.” Keurig Support assures us that all of their machines have been thoroughly tested and proven to be food-safe. All parts that come into contact with water, including K-Cups are BPA free and FDA approved for the temperatures they encounter. However, California Proposition 65 requires that manufacturers provide a warning if any of over 800 listed harmful chemicals are present in products sold in California.
Keurig K10 (B31) Mini Plus Price
We agree with the majority of users who feel that the Keurig K10 (B31) Mini Plus Brewing System is a good choice for home use, provided:
- you don’t mind having to wait for each cup of water to heat,
- you are happy with K-Cups (or don’t mind experimenting to produce good-tasting ground coffee with the My K-Cup reusable filter),
- and you feel that 10 ounces is enough coffee per cup (or are comfortable doing a second brewing to produce a larger amount)
Note that you may need to clean the needles often to keep it running smoothly, or adjust how you install the K-Cups.
We appreciate the Mini Plus’s small footprint, portability, ease of use, wide range of colors and the variety of available coffees and assorted beverages.