Comparison Review: B31 and B40

The Keurig coffee makers are a very reliable brand, and they will constantly give you a wonderful coffee any time of the day. If you have heard how good the Keurig B31 and the B40 are, you may wonder which one you should buy. Both of the models are great quality models, but in order to help you choose between the two, I have compared them so you can see how they perform, therefore helping you to buy the right one.

Brewing Options & Aspects

The Keurig B31 gives you the opportunity to brew three different sized cups of coffee, six, eight and ten ounces, giving you the perfect sized cup. This is great if you’re not one to drink a large cup all day. The Keurig B40 comes with just two different cup sizes: large and medium. This isn’t as much of a choice, but it’s perfect for those of you who simply don’t want a small cup of coffee, as only a medium or large will suffice.

Keurig B31 Mini Plus Coffee Brewing Machine

Keurig K10/B31 MINI Plus Brewing System, Black
Amazon Price: $99.99 $90.50 Buy Now
(price as of Dec 9, 2013)

Time to Brew

The great news is the B31 can brew your favorite coffee in two minutes, which isn’t much time at all. This means you can get up in the morning, switch the machine on and know that your first cup of the day is just a few moments away. The Keurig B40 takes a little longer to give you a cup of coffee, in fact, it’s twice as long. However, four minutes is not a huge length of time to wait, and in that time your coffee will taste just as good and as fresh as one brewed in the B31.

Keurig B40 Elite Brewing Coffee Machine

Keurig B40 Elite Brewing System
Amazon Price: $119.99 $113.95 Buy Now
(price as of Dec 9, 2013)

Size of Water Reservoir

The B31 comes with a single use reservoir; this means that it will only hold enough to give you one 10 ounce cup. If all you need is one cup of coffee at a time, you won’t be missing out on anything. If the coffee maker is used by a lot of people, they will have fresh-tasting coffee within a very short space of time, and that’s not a bad thing. The Keurig B40 is slightly different when it comes to the capacity of its water reservoir. This model is capable of holding 48 ounces of water at any one time. This means you can enjoy many cups of coffee through-out the day and you won’t have to keep refilling it. What’s more is it makes the B40 suitable for a lot of people to use as it’s capable of giving you approximately 6 medium sized cups before having to be refilled. 

Size (Dimensions)

It’s usually a good idea to work out how much space in your office or kitchen you have to house your new coffee maker. The last thing you want to do is buy one that’s too big, or purchase one that’s too small when a larger model would have been more suitable. Once you have worked out how much room you have, you can then decide which one is the right one for you. 

Keurig B31 Dimensions: 12.7 x 12.2 x 12.7 inches (H, W, D).
Keurig B40 Dimensions: 14.9 x 12.2 x 14.2 inches (H, W, D).

As you can see the B40 is a slightly bigger model, which is to be expected as it has a larger water reservoir, but it’s not overly big, which means it’s still ideal for use in your kitchen or small office. 


The B31 weight 10.2 pounds, which isn’t very heavy and is what you should expect from a single use coffee maker. If you would like to put it on a shelf, please make sure the shelf is strong enough to hold the model. The B40’s shipping weight is 14 pounds, which is a little more than the B31, but it’s still very good considering it’s just that bit bigger. 

Additional Features

The Keurig B31 comes with a removable drip tray, which makes it so much easier to maintain. This option also has the ability to make you a cup of tea or cocoa if you wish. 
The Keurig B40 also has a removable drip tray, as well as a descale indicator telling you exactly when it needs to be cleaned.

Conclusion - Which Keurig coffee machine will you buy the B31 or B40?

The Keurig B31 and B40 are two great coffee makers that will work well for you each and every time. The B31 is ideal if it’s not going to be used very often, but the B40 is great if a few of you want a freshly brewed cup of coffee through-out the day.

Have You Considered Upgrading to the B60?

Keurig B60 Special Edition Brewing System
Amazon Price: $299.00 $137.99 Buy Now
(price as of Dec 9, 2013)

Also, if you have any questions, comments or concerns regarding either the comparison overview guide - B31 Vs B40 - or about either coffee machine B31 or B40 specifically (e.g. if you are seeking advice or clarification over an aspect mentioned above) then please do not hesitate to make them in the comments section that you will find just below and we will be sure to get back to you.

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