10 Best Mini Split Units 2025 in the United States

The Pioneer Diamante Series ductless mini-split system offers a solid balance of efficiency and comfort for cooling and heating spaces up to about 450 square feet. With a 12,000 BTU capacity and a high SEER rating of 20, it’s energy-efficient, which means it can save on electricity bills compared to older or less efficient models. The HSPF rating of 10 indicates good heating performance during colder months. Noise level is fairly low at 40 dB, so it should run quietly without disturbing your daily activities. This is a single-zone system, ideal if you want to control the temperature in one room or area rather than multiple zones. The included 16-foot installation kit and accessories make setup easier, though proper installation might still require a professional to ensure everything runs smoothly and efficiently.

The unit runs on standard 115V power, and its compact design fits well in most spaces without being obtrusive. On the downside, it is a single-zone system, so it won’t be the best choice if you need to heat or cool multiple rooms independently. Also, while installation components are included, the complexity of setup means this isn't a simple DIY project for everyone. The 40 dB noise level is low but could be noticeable in very quiet environments for sensitive users.

This mini-split is a great option for homeowners or light commercial users looking for an energy-efficient, quiet, and reliable heating and cooling system in a medium-sized space.

The Della Vario 18000 BTU Mini Split AC is a solid choice if you need to cool or heat a medium-sized space up to about 1000 square feet. Its 1.5-ton capacity and 19 SEER2 rating mean it’s energy efficient and can save on power bills compared to older or less efficient units. It also operates quietly at 50 dB, so it won’t be disruptive in your home. The unit features modern conveniences like WiFi and Alexa compatibility, allowing easy control from your smartphone or voice commands. It’s equipped with a heat pump that works even in temperatures as low as -4°F, making it useful for mild heating in colder months.

The system includes smart airflow controls and multiple modes like sleep and energy-saving eco mode for comfort and efficiency. However, it supports only a single zone, so it’s limited to one room or open area rather than cooling multiple separate rooms. Installation is more involved than window units; it requires professional help because of line-set vacuuming and refrigerant adjustment, so DIY installation isn’t recommended. While the included installation kit is convenient, this adds to the overall cost.

If you want a reliable, energy-saving mini-split for a single room or space with quiet operation and smart features, the Della Vario is a good pick, but factor in professional installation and single-zone use before deciding.

The COSTWAY 12000BTU Mini Split Air Conditioner & Heater is a versatile unit designed to cool and heat rooms up to 750 sq. ft. It boasts a high Seasonal Energy Efficiency Ratio (SEER) of 20, indicating excellent energy efficiency, which can translate to lower energy bills. The unit also features an inverter compressor, which allows for more efficient and quieter operation by adjusting the power supply frequency. At 51 dB, it has a moderate noise level, which should be acceptable for most users in living rooms or bedrooms.

Its pre-charged R32 refrigerant is a more eco-friendly option compared to older refrigerants, supporting a greener choice for environmentally conscious consumers. With five operation modes (auto, cool, dry, heat, and fan) and various fan speeds, the unit offers flexibility and can cater to a range of comfort preferences throughout the year. The self-cleaning feature and auto-defrost function add convenience, ensuring the unit remains efficient and maintains clean air. Users will find the included remote control with a display screen helpful for managing the unit from a distance.

Maintenance is made easier with the washable filter and self-cleaning capabilities. However, installation must be performed by a licensed HVAC installer, which could add to the initial cost and complexity. Additionally, while the unit comes with a solid warranty (5 years for parts, 8 years for the compressor), those who prefer a quieter operation might find the 51 dB noise level slightly higher than some ultra-quiet models available on the market. Its robust feature set, energy efficiency, and year-round functionality make it a strong contender in the mini-split category, particularly for medium-sized rooms.