The Bosch HMB30155UC is one of the most popular built-in microwaves on the market — and a model we are very familiar with when it comes to building custom trim kits. If you own one or you're about to buy one, here's a rundown of your trim kit options.
About the Bosch HMB30155UC
The Bosch HMB30155UC is a 24" built-in microwave from the Bosch 300 Series. The unit itself measures 13-5/8" H x 24-3/8" W x 19-11/16" D. It's designed to be compatible with a trim kit for built-in installation, though it can also be used as a countertop microwave.
When installed as a built-in, a trim kit centers the microwave in the opening and provides a decorative frame that covers the gap between the microwave and the surrounding cabinetry, giving it a clean, built-in look.
OEM Trim Kit Options from Bosch
Bosch makes two trim kits designed for the HMB30155UC:
HMT5055 — 30" Trim Kit The face frame measures approximately 29-3/4" wide x 20-7/16" tall. It calls for a cabinet cutout of 19-7/8" H x 28-7/16" W x 23" D. It runs about $299 at most retailers.
HMT5755 — 27" Trim Kit Same concept, narrower frame. It measures approximately 26-11/16" wide x 20-7/16" tall and calls for a cabinet cutout of 19-7/8" H x 25-7/16" W x 23" D. Also around $299.
Both are stainless steel and both include the mounting hardware needed for installation.
When the OEM Trim Kits Don't Work
We get a lot of emails about this microwave, and more often than not, the conversation starts because one of the OEM trim kits won't work for the customer's situation. In order for the Bosch OEM trim kit to work, a few things have to line up.
Your cutout has to match the Bosch specs exactly. The OEM trim kit includes a base that raises the microwave up and centers it in the opening. If your cutout doesn't match the specified height, the microwave won't sit centered — it'll be off vertically, and the frame won't line up the way it's supposed to.
Adjacent cabinetry can limit your options. The OEM trim kits are 20-7/16" tall, and a lot of kitchens have doors, drawers, or other components directly below the microwave opening that won't accommodate a frame that tall. The trim kit would physically interfere with whatever is above or below it. On the other side of that equation, some openings are taller than what the OEM frame was designed to cover — and the trim kit just won't fill the space.
You might be a non-standard width. Maybe it's 28" or 29" — too wide for the 27" kit, too narrow for the 30" kit. Neither OEM option will look right. Or maybe you're replacing a larger microwave and you need a kit that is 31", 33" or wider. The 30" trim kit won't cover that.
The bottom line is that the OEM kits work well when everything lines up perfectly. But kitchens aren't always that cooperative — especially when you're dealing with existing cabinetry, adjacent components, or a cutout that was originally built for a different microwave.
That's Where a Custom Trim Kit Comes In
We build custom microwave trim kits specifically for situations like these. The Bosch HMB30155UC is a model we are very familiar with.
Here's how our process works: you place your order, and we send you a detailed measurement form that walks you through taking measurements and specifying the size of your trim kit. Once we get those measurements back, we plan and fabricate your trim kit. If you have any questions along the way, we are happy to help.
A few things that set a custom trim kit apart from the OEM options:
It works with any cutout size. Whether your opening is 26" wide or 32" wide, we build to any size. Same with height.
It's made to fit around any limitations you might have with adjacent cabinetry or adjacent components. If you've got drawers below that limit the height, or an opening that's taller than the OEM frame can cover, we build around it.
Made from true stainless steel. Our trim kits are fabricated in our shop in Tulsa, Oklahoma.
Our kits feature custom risers that raise and center the microwave while providing a decorative face frame for a seamless built-in appearance. Ventilation slots on the top and bottom are included as standard on every kit.
We also offer finish options in matte black, matte white, and black stainless if your kitchen calls for it.
Our premium custom microwave trim kits are currently $349 with free shipping.
How to Decide
If your cabinet cutout matches one of the two Bosch OEM sizes (27" or 30" wide, ~19-7/8" tall) and you don't have any conflicts with adjacent cabinetry, go with the OEM kit. It's designed for the microwave and it'll work.
If your cutout is a different size, if adjacent components are limiting your options, or if you're replacing a larger microwave and the opening doesn't line up - we can help.
