For anyone that knows the story of Goldilocks and the Three Bears, the micro-ATX (mATX) form factor makes a lot of sense. Sometimes, your case and motherboard are just a bit too big, with so many extra features you’ll never need but will take up valuable space on your desk or in your room. And sometimes, your case and motherboard are just too small, making building a torture test and leaving no room for your components to breathe and cool off to attain maximum performance. But then, you find that magical size in-between and discover that it has everything you need and nothing you don’t, while giving you plenty of choices that range from absolutely tiny to almost ATX-size. Goldilocks might not have ended with the creation of the mATX form factor, but it might as well have given how perfectly it fits in.
Micro-ATX has managed to become the happy medium between the very very tiny ITX form factor and the quite large ATX form factor. But even with mATX, there is quite a bit of variety. And plenty of builders want to save as much space as possible, without entering all the way into mini-ITX territory. So for someone looking for the best, smallest mATX case available today, our recommendations below will guide you based on what YOU find most important. We are looking for a small size, but not at the expense of quality.
With those criteria in mind, here are our recommendations for best smallest mATX PC cases:
Smallest Micro-ATX Cases – Our Recommendations
| Award | Design | Model |
|---|---|---|
| Best Smallest Budget mATX Case |  | Antec Slim VSK2000-U3 |
| Best Silent Smallest mATX Case |  | CoolerMaster Silencio S400 |
| Best Versatile Value Smallest mATX Case |  | CoolerMaster MasterBox Q300L |
| Best Portable Value Small mATX Case |  | CoolerMaster MasterBox Q300P |
| Best Looking Smallest mATX Case |  | Corsair Crystal 280X |
| Alternative Aesthetic Small mATX Case |  | Corsair Carbide Air 240 |
Best Smallest Budget mATX Case
If you are looking to keep costs down and don’t mind a very slight increase in space to save a few bucks, Antec offers a similarly small case called the Antec Slim VSK2000-U3 for a very reasonable $50 (less than half of the Minuet 350). This case is actually even smaller at 12.3L, but offers only a 250W PSU, and sports a similar subtle design, making it perfect for the budget builder trying to keep the size footprint to an absolute minimum.
Best Silent Smallest mATX Case
While windowed cases are all the rage, some builders still prefer a more workman-like product that is very sober, but very functional. And amongst the prime features of a case of any size is its ability to dampen fan noise and keep things quiet. While all cases will help to a degree, some cases are bit for silence. CoolerMaster has offerings at the ATX size for this (Silencio 550) that are relatively well-known, so they decided to expand to the mATX form factor and build our recommendation for best silent smallest mATX case: the CoolerMaster Silencio S400.
The beauty of these cases is not only that they dampen sound, or that they are small. It’s that CoolerMaster has taken care to ensure that those are only some of the features. To allow for customization and increased ventilation, the S400 has the option to remove the top panel and remove the sound dampening aspect for slightly more noise, but also much more airflow. Similarly, the front mount is reversible, so that the front panel door can open on either side of the case based on which direction allows for better airflow. This type of detailed thought, combined with the typical CoolerMaster build quality and inclusion of the quiet FP120 fans to really double-down on the silence aspect, make this case exciting for anyone looking to maximize their zen-ness while building their rig. At $90, this case is a great buy for our quiet, tiny mATX builders.
Best Versatile Value Smallest mATX Case
While the Antec Slim VSK2000-U3 is extremely affordable, not everyone is interested in quite so small a case, or one that might be limiting in terms of GPU/cooling options. And while quiet is nice, not everyone needs the dead silence of the Silencio S400. So for anyone looking for a very affordable, very versatile case, we can look at a different offering from our well-respected manufacturer CoolerMaster. For our best versatile value smallest mATX case, we recommend the MasterBox Q300L.
In terms of value, it is very tough to beat the MasterBox Q300L. The typical price is right near $45, and even lower on sale. But for the price, this case is packed with features into its tiny package. A comprehensive front panel that can be moved to different placements, a beautiful big window, a nice cable management spot behind the motherboard, and magnetic dust filters to keep the inside clean. Other than having an acrylic instead of tempered glass window, it really is tough to complain with the quality for the price, hence the recommendation in our value category.
Best Portable Value Small mATX Case
And if all of that wasn’t enough, CoolerMaster took the same interior and added different choices for outer fittings to really be sure you get exactly what you need. If you are looking for a tiny portable PC that still uses the mATX form factor, the MasterBox Q300P adds some great removable handholds to help you bring your PC to where it needs to be. This one is a bit more expensive at $85, but includes two RGB fans and an RGB hub, so you still get great bang-for-your-buck for a versatile, small, portable mATX case.
Best Looking Smallest mATX Cases
This category is tough, because it is very subjective. But given that a couple of the options above are at-best subtle, and at-worst boring, we wanted to include a category that shows off some of the beautiful cases that manage to stay small while still using the mATX form factor. Both come from the same high-quality manufacturer, and one of them has been mentioned on this site before. Our two recommendations for best aesthetics in a small mATX case are the Corsair Crystal 280X, and the Corsair Carbide Air 240.
In terms of pure size, the Carbide Air 240 is the smaller of the two and is truly a marvel. The full-size acrylic window combined with the sleek form, asymmetric front meshing and front panel I/O, and well-thought out design come together to make a very attractive mATX case. The optimization for airflow and ability to hold a dual-fan GPU, while maintaining the small footprint, are great examples of finding the balance between smallness and function. Unless you really want to go as tiny as possible like with the Antec offerings or an ITX build, this case will give you plenty of performance and great looks, all for right around $150.
And on the slightly bigger side, the Crystal 280X is just a beautiful chassis. The dual-compartment layout and double glass paneling help keep cables clean while showing off the insides of your rig. It’s not the tiniest case available, and for some reason it seems to ‘present’ as larger than it actually is, but if you want a build that looks terrific, uses the mATX form factor, and does not take up your entire desk, the Crystal 280X has great build quality and will impress anyone you meet. It’s not cheap at $170 (including two fans and a hub), but you get what you pay for, which is a beautifully designed, well-built mATX case.
Conclusion
Whether you want the absolute tiniest mATX to rival even many ITX builds, or something that just uses the most of what mATX has to offer and really differentiates itself from ATX, this guide hopefully shed some light on what cases to consider. Depending on what is most important to you, mATX offers a diverse selection of small cases, many of which excel at specific attributes like silence or portability, and others that really take mATX to the extreme limits of compactness. Make sure you think about what exactly you are looking for before making your purchase, but once you’ve decided on your priority, this guide should help make the buying process a little bit easier.