Comparison: Best 30 Inch Built In Microwave (Updated | Dec 8th)

Most 30‑inch models offer between 1.2 cu ft and 2.2 cu ft of interior space. If you often cook large dishes or multiple items at once, the 2.2 cu ft units from Frigidaire or Summit provide more flexibility. For smaller households, a 1.2 cu ft model like the COSMO Haven may be sufficient and can save a few inches of depth.

Higher wattage generally means faster cooking and more even heating; the Summit and Frigidaire models deliver 1200 W, while COSMO and some other units are rated at 1000 W. The 950 W dual‑function microwave‑convection combo from the 30‑inch convection line is slightly lower but compensates with its additional cooking modes. Choose based on whether speed or versatility is your priority.

A trim kit ensures a seamless fit in a 30‑inch cabinet opening and is essential for a professional look. Frigidaire’s GMBS3068BF and PMBS3080BF require the separate 30‑inch trim kit (PMTK3080AF). Summit’s 30‑inch microwaves ship with a full trim‑kit package, while many COSMO models do not list a kit, so you may need to purchase it separately.

Convection and air‑fry functions add browning, crisping, and roasting that a standard microwave cannot achieve. The KoolMore and KoolMore Reserve units combine microwave, convection, and air‑fry in one appliance, offering the most cooking flexibility. If you rarely need these extra modes, a plain microwave like the Frigidaire or Summit may provide better value.

COSMO models include four automatic presets (melt, soften, popcorn, beverage) plus smart defrost options. Summit microwaves provide a broader set of one‑touch programs such as potatoes, pizza, frozen dinners, and a +30‑seconds shortcut. Frigidaire relies on sensor cook technology rather than a long list of presets, focusing on automatic power and time adjustments.

Most of the listed models come with a one‑year limited warranty, including COSMO and KoolMore units, which also highlight U.S.-based customer support. Frigidaire typically offers a similar one‑year warranty but may provide extended coverage through optional service plans. Check the warranty terms for coverage of parts, labor, and any specific exclusions before purchasing.

While exact pricing isn’t provided, larger capacity models like the Frigidaire Gallery Series and Summit usually command a higher price due to greater cooking volume and higher wattage. The 1.2 cu ft COSMO Haven models are typically more budget‑friendly but lack the extra space and power of the larger units. Evaluate how often you need the extra capacity to decide if the price premium is justified.

Most 30‑inch units require a cutout width of about 24‑25 inches, with trim kits extending the visible width to 30 inches. If your cabinet opening is narrower than the required cutout, you’ll need to modify the cabinet or choose a smaller model. Summit’s 27‑inch version may fit tighter spaces while still offering a 2.2 cu ft interior.