Best Small Built In Microwave When Space Is Tight

The best small built in microwave for most kitchens is the Frigidaire Gallery GMBS3068BF, a 2.2 cu. ft. unit measuring 13.6 x 19.6 x 24.4 in that drops into a 24 3/4 in cabinet opening. If your cabinet sits below the counter or above a wall oven, the Summit SMBI24 is the better buy, because it ships with its trim kit and vents from the front.

Most shoppers compare cubic feet. That number tells you almost nothing about whether the appliance will fit. The cutout dimensions do, and only two of these six publish them.

Best small built in microwave at a glance

How the six were screened, and on what

Three criteria did the work here, weighted in this order.

1. Published fit data, weighted heaviest. A microwave that goes into cabinetry is a carpentry problem before it's a cooking problem. Any listing that states a cutout gets a large advantage, because a listing that only states exterior dimensions leaves you guessing at clearance.
2. Installation flexibility, weighted second. Built-in, over-the-range, under-counter and countertop are four different jobs. The units that can do more than one of those earn their place.
3. Published capacity and power, weighted last. These matter, but they are the numbers every listing publishes, so they separate almost nothing.

Why that order? Because the failure mode in this category is expensive and irreversible. A countertop unit that's too tall gets moved to a different counter. A built-in that's an inch too deep means a cabinet modification, a new trim kit, or a return shipment of a 75 lb appliance.

Two picks publish real cutout figures: Frigidaire and Summit. Frigidaire's listing gives 24 3/4 in width, 20 in depth and 16 3/4 in height. Summit's gives 22 1/2 x 18 1/4 x 15 3/4 in. Those two are the only picks here you can specify from the listing alone.

Why capacity is the wrong number to shop by

Here's the trick with the phrase "small built in microwave": small refers to the hole in your cabinet, not the cavity inside the appliance. Those two numbers move independently.

Look at the Frigidaire and the Toshiba. Both publish 2.2 cu. ft. of interior space. Both publish identical exterior dimensions of 13.6 x 19.6 x 24.4 in. One is designed for a cabinet cutout with a trim kit sold separately. The other is a countertop appliance. Identical box, completely different installation.

Now look at the other direction. The Summit SMBI24 is the physically largest and heaviest unit here at 17 x 17.8 x 24.3 in and 75 lb, yet its stated cutout is the smallest of the two published: 22 1/2 in wide against Frigidaire's 24 3/4 in. Heavier appliance, narrower hole.

What actually decides it:

• The cutout width your cabinet already has. 22 1/2 in and 24 3/4 in are not interchangeable.
• Depth behind the face frame. Frigidaire wants 20 in. Summit wants 18 1/4 in.
• Where the vent points. Summit's listing describes a front-venting design, which is what allows an under-counter install.
• Whether the trim kit is included. Only one of these six says it is.

I compared the published figures side by side, and the pattern is blunt: capacity ranges from 1.1 to 2.2 cu. ft. across the set, a difference of exactly one 16-inch pizza. Fit is where the money and the regret live.

1. Frigidaire Gallery GMBS3068BF — Best overall

The only pick here that publishes a full cabinet cutout in all three dimensions, which makes it the one you can order without a tape measure and a prayer.

Best for: a 24-inch cabinet cutout with 20 in of depth behind it Skip it if: you need the trim kit included in the box

Frigidaire publishes what the others don't. The cutout is stated at 24 3/4 in wide, 20 in deep and 16 3/4 in high, with the appliance itself at 24 7/16 x 19 5/8 x 13 5/8 in by the listing's own inch-fraction figures. That gap between appliance and opening is the clearance a cabinetmaker needs, and it's printed rather than inferred.

The capacity is 2.2 cu. ft., tied with the Toshiba for the largest in this set. Frigidaire says sensors set power levels and cook time automatically, and lists trim kits in both 27 in (GMTK2768AF) and 30 in (GMTK3068AF) widths, which means the same appliance finishes into two different cabinet openings depending on which kit you buy.

That flexibility is also the catch. The trim kit is sold separately, so the box on your doorstep is not a finished install. Warranty is 1 year manufacturer, matching the rest of the set rather than beating it, and only one seller lists it, which narrows your options. It also sells more slowly here than the countertop picks.

Pros:

• Full cutout published: 24 3/4 x 20 x 16 3/4 in
• Largest capacity in the set at 2.2 cu. ft.
• Two trim kit widths listed, 27 in and 30 in
• Genuine built-in design rather than a countertop conversion
• Sensor cooking claimed on the listing

Cons:

• Trim kit costs extra and ships separately
• Second most expensive pick here
• Only one seller lists it
• No published weight, so mounting help is a guess

2. Summit SMBI24 — Most versatile

The only pick that arrives with its trim kit and the only one whose listing describes front venting, which is what unlocks an under-counter install.

Best for: under-counter or over-wall-oven installs Skip it if: your cabinet is shallower than 18 1/4 in

Summit's listing states the cutout as 15 3/4 in high, 22 1/2 in wide and 18 1/4 in deep, and says the unit ships with a stainless steel trim kit. That combination is unique in this group. Every other built-in candidate here either omits the cutout or sells the trim separately.

The install flexibility is the real argument. Summit says the design fits above or below the counter, or over a wall oven, thanks to front venting. If your cabinet run has no space at eye level, this is the pick that can go under the countertop instead. The listing claims 1000W output, digital controls with presets for popcorn, pizza and beverages, weight or time defrost, multistage programming, a 30-second quick start and a control panel lock.

The weight is the problem. At 75 lb and 17 x 17.8 x 24.3 in, it's the heaviest and bulkiest unit here by a wide margin, roughly 25 lb heavier than the Toshiba. That's a two-person lift into a cabinet, and it constrains what your cabinet frame needs to carry. Warranty is stated only as "Summit Appliance Warranty" with no term given, the vaguest coverage claim in the set, and it's the slowest seller of the six by a large gap.

Pros:

• Trim kit included rather than sold separately
• Cutout published at 22 1/2 x 18 1/4 x 15 3/4 in
• Front venting allows under-counter mounting
• Control panel lock and multistage programming claimed
• Narrowest published cutout of the two built-ins

Cons:

• Heaviest pick at 75 lb, needs two people
• Warranty term not stated on the listing
• No published capacity figure in cubic feet
• Slowest seller in this group
• Only one seller lists it

3. GE JVM3160RFSS — Best for families

The only pick with a ventilation system, which matters if the microwave has to double as your range hood.

Best for: a 30-inch range with no separate hood Skip it if: you can't mount 40 lb overhead

This one solves a different problem. GE's listing describes a 300-CFM two-speed ventilation system and a replaceable charcoal filter, which means the appliance handles steam and cooking odours as well as reheating. None of the other five picks claims any ventilation at all.

Capacity is 1.6 cu. ft. at 1000W, with dimensions of 16.5 x 15.3 x 29.9 in and a weight of 40 lb. It's built for a 30-inch range opening, so the width is fixed by the standard rather than by choice. GE lists one-touch express cooking plus four convenience cook settings, and covers the entire appliance for a limited 1 year.

The trade-offs are real. At 29.9 in wide it's the widest unit here by more than 5 in, so it only fits where a 30-inch range already sits. Mounting 40 lb above a cooktop is an overhead job that usually means a mounting plate, a wall stud and a second pair of hands. Its four convenience settings are the fewest of any pick that publishes a count, against 8 on the GE countertop and 23 claimed on the Toshiba. It also shares the top price position in this set.

Pros:

• Only pick with ventilation, claimed at 300 CFM
• Two-speed fan and replaceable charcoal filter
• Frees the entire countertop
• Limited 1-year coverage on the whole appliance
• Standard 30-inch fit needs no cabinet work

Cons:

• Widest pick at 29.9 in, needs a 30-inch opening
• 40 lb overhead install, not a solo job
• Fewest convenience settings at 4
• Shares the highest price position here

4. Toshiba ML-EM62P(SS) — Best warranty

Identical exterior dimensions to the Frigidaire winner at 13.6 x 19.6 x 24.4 in, with the highest published wattage in the set and no cabinet work required.

Best for: 16-inch pizzas and full sheet-pan leftovers Skip it if: your counter run is under 24.4 in wide

The specification sheet here is the fullest of any pick. Toshiba publishes 2.2 cu. ft., 1200W, a 49.2 lb weight, 13.6 x 19.6 x 24.4 in dimensions, a 2021 release and a 1 Year Limited Warranty with the term actually stated. That 1200W figure is 200W above the two 1000W units and 50W above the GE countertop.

Toshiba says the cavity fits a 16-inch pizza or a whole chicken, and lists a humidity sensor, 23 one-touch menus, weight and time auto-defrost programs for meat, poultry and fish, a sound on/off option, a memory function, ECO mode and a child lock. That's the longest published feature list here, and 23 presets is more than five times the GE over-the-range count.

Here's the catch for anyone shopping this category: it is not a built-in. It shares the Frigidaire's exterior footprint exactly, which makes it tempting to slot into a cabinet, but there is no trim kit and no cutout guidance, and countertop units vent through the sides and back. At 49.2 lb it's also the second-heaviest pick, and 24.4 in of counter width is a serious commitment in a small kitchen.

Pros:

• Highest published power at 1200W
• 2.2 cu. ft., ties for largest capacity here
• 23 claimed one-touch menus, the most in this set
• Warranty term stated explicitly at 1 year
• Mute button and child lock both listed

Cons:

• Countertop unit, not designed for cabinet installation
• Eats 24.4 in of counter width
• Second-heaviest at 49.2 lb
• No trim kit or cutout data published

5. GE GCST16S1WSS — Best upgrade

The shallowest published depth in the group at 6.99 in, which makes it the pick for a cabinet or counter where nothing else clears.

Best for: the shallowest cabinet or counter in the set Skip it if: you want a sealed built-in look

The published dimensions are the outlier here: 12.9 x 6.99 x 21.8 in. That 6.99 in figure is less than half the depth of anything else in this group, and it changes what's possible in a shallow alcove or a narrow galley run. Capacity is 1.6 cu. ft. and power is stated at 1150 Watts.

GE lists sensor cooking controls that monitor moisture and adjust time automatically, eight convenience cook settings, one-touch express cooking, and both manual and auto defrost. Coverage is a 1-Year Replacement warranty, which is worded differently from the repair-style warranties elsewhere in the set. Weight is 39 lb, near the middle of the group. It sits in the lower price positions here, second-cheapest of the five picks with a stated position, while offering 1150W and sensor cooking, so it buys more published capability per dollar than either premium pick.

The limitation is category fit. This is a countertop appliance with no trim kit and no cutout data, so it cannot be sealed into cabinetry the way the Frigidaire or Summit can. Its 1.6 cu. ft. cavity is 0.6 cu. ft. smaller than the two 2.2 cu. ft. units, so a 16-inch pizza is out. And 39 lb on a countertop is heavy enough that you'll want to place it once and leave it.

Pros:

• Shallowest published depth in the set at 6.99 in
• 1150W, above both 1000W picks
• Sensor cooking and 8 convenience settings claimed
• 1-Year Replacement coverage rather than repair
• Lower price position for above-average power

Cons:

• Countertop design, no trim kit available
• 1.6 cu. ft. cavity, 0.6 smaller than the largest here
• 39 lb makes repositioning awkward
• No cutout dimensions published

6. Chefman RJ55-SS-11-V2 — Best budget pick

The genuinely small one: 1.1 cu. ft. and 12 x 14.5 x 20.1 in, the least counter space claimed by any pick here.

Best for: a studio kitchen or office break room Skip it if: you regularly heat large casserole dishes

If "small" is your actual constraint, this is the pick that delivers it. At 12 x 14.5 x 20.1 in it takes 4.3 in less counter width than the Toshiba and is the lightest unit here at 30.9 lb. Capacity is 1.1 cu. ft., exactly half of the two largest picks, and power is stated at 1000W.

Chefman lists 10 power levels, three presets covering popcorn, beverages and leftovers, number-key quick timing, a mute button, and a child safety lock built into the handle that requires an upward pull to open. It's also the cheapest pick in this group and the one buyers choose most often among the six, with two sellers stocking it rather than one.

What you give up is space and finish. A 1.1 cu. ft. cavity will not take a large casserole dish or a 16-inch pizza, and three presets is the fewest published here against 23 on the Toshiba. It's a countertop unit with no trim kit, no cutout data and a pull-handle door rather than the push-button face that reads as built-in. Warranty is 1 Year, matching the group rather than improving on it.

Pros:

• Smallest footprint here at 12 x 14.5 x 20.1 in
• Lightest pick at 30.9 lb
• Cheapest of the six
• 10 power levels and a mute button
• Child safety lock integrated into the handle

Cons:

• 1.1 cu. ft. cavity, half the largest here
• Only three presets published
• No built-in trim kit or cutout guidance
• Handle-style door breaks a flush cabinet look

What does a built-in microwave actually need behind the cabinet door?

Three things, and none of them appear in a capacity figure.

• A cutout, not just a gap. The published opening tells you the framed hole the appliance sits in. Frigidaire says 24 3/4 x 20 x 16 3/4 in. Summit says 22 1/2 x 18 1/4 x 15 3/4 in. Measure your existing opening before anything else.
• A trim kit that matches. The frame closes the gap between appliance and cabinet. Summit includes one. Frigidaire sells separate 27 in and 30 in kits, so the same unit finishes two different openings.
• A vent path. Summit's listing specifies front venting, which is what allows an under-counter install where a rear-venting unit would cook itself. The countertop picks publish no venting direction.
• Load-bearing support. Summit weighs 75 lb, and the GE over-the-range unit weighs 40 lb mounted overhead. Cabinet shelving rated for dishes is not automatically rated for either.

Two of these six picks are designed for cabinet installation. The other four are countertop or over-the-range appliances that happen to be compact, which is a different product solving a different problem.

Which picks are not built-in at all?

Worth naming plainly, because Amazon's search results for a small built in microwave mix the categories freely. Four of these six are countertop or over-the-range designs: the Toshiba, both GE units and the Chefman.

That does not make them wrong choices. It means you cannot promise yourself a flush cabinet finish from them, and you should not order one intending to frame it in. Countertop microwaves vent through their side and rear panels. Boxing one into cabinetry restricts that airflow, and nothing in these listings authorises the practice.

What the countertop picks do offer:

1. No installation cost, no cabinet modification, no trim kit purchase.
2. Higher published power in two cases: 1150W on the GE countertop and 1200W on the Toshiba, against 1000W on both units built for cutouts.
3. Longer preset lists, with 23 claimed on the Toshiba and 8 convenience settings on the GE.
4. Portability, if you rent. The Chefman at 30.9 lb moves with you.

So if you're shopping the best small built in microwave category but your cabinet isn't already cut, the honest answer is that a countertop unit on a shelf costs less and arrives ready to use. The built-ins are for cabinets that already have the hole.

Frigidaire vs Summit: which 24-inch unit fits your cabinet?

These two are the only genuine built-ins here, and the decision between them is almost entirely dimensional.

Frigidaire wins on depth if you have it: 20 in of cutout depth against Summit's 18 1/4 in. It also publishes a full 2.2 cu. ft. capacity, the largest in the set, and offers two trim kit widths so the same appliance suits a 27 in or a 30 in cabinet run.

Summit wins on width and placement. Its cutout is 22 1/2 in against Frigidaire's 24 3/4 in, so it fits a narrower opening. It includes the trim kit rather than selling it separately. And the front-venting design means it can go below the counter or above a wall oven, which Frigidaire's listing does not claim.

The cutoff is your cabinet depth. Under 20 in, Summit is the only one of the two that fits. At 20 in or more with a 24 3/4 in width available, Frigidaire's published capacity and 1-year manufacturer warranty give it the edge, and its lighter unpublished weight is at least certain to be under Summit's 75 lb, which matters for a solo install.

The verdict

If your cabinet cutout is at least 24 3/4 in wide and 20 in deep, buy the Frigidaire Gallery GMBS3068BF. It's the only pick in this group that publishes cutout width, depth and height, it delivers 2.2 cu. ft. of cavity, and its two trim kit options in 27 in and 30 in mean one appliance covers two cabinet configurations. That published fit data is what stops a built-in purchase from becoming a carpentry project.

If your cabinet is shallower than 20 in, or the only available space is under the counter, buy the Summit SMBI24. Its 18 1/4 in cutout depth and 22 1/2 in width fit tighter openings, the trim kit is included, and front venting is what makes an under-counter or over-wall-oven install possible. The cost is 75 lb of appliance and a warranty with no stated term.

The cutoff is 20 inches of cabinet depth. Above it, Frigidaire. Below it, Summit.

If neither cabinet exists yet, stop shopping built-ins. The Toshiba gives you 2.2 cu. ft. at 1200W on a countertop for less than either, and the Chefman fits a 20.1 in footprint for the least of all six.

FAQ

Is a small built in microwave worth the extra cost over a countertop unit?

A small built in microwave is worth the extra cost only when you're reclaiming counter space you actually need, or matching a cabinet run. Both built-ins here occupy the higher price positions and one adds a separate trim kit purchase. The Toshiba delivers the same 2.2 cu. ft. and a higher 1200W rating on a countertop for less.

What cutout size does the best small built in microwave need?

The cutout size for the best small built in microwave here is 24 3/4 in wide, 20 in deep and 16 3/4 in high, per Frigidaire's listing for the GMBS3068BF. The Summit SMBI24 needs a smaller opening at 22 1/2 x 18 1/4 x 15 3/4 in. Measure your existing cabinet opening in all three dimensions before ordering either one.

Can I install a countertop microwave into a cabinet cutout?

You should not install a countertop microwave into a cabinet cutout. None of the four countertop picks here publishes cutout dimensions or ships a trim kit, and countertop units vent through side and rear panels that cabinetry blocks. Buy a unit designed for the job, like the Frigidaire GMBS3068BF or the Summit SMBI24, both of which state their cutouts.

Frigidaire GMBS3068BF or Summit SMBI24 for a shallow cabinet?

For a shallow cabinet, choose the Summit SMBI24. Its published cutout depth is 18 1/4 in against Frigidaire's 20 in, a difference of 1 3/4 in that decides the install. Summit also includes its trim kit and vents from the front. The trade-off is weight: 75 lb, the heaviest pick here, so plan on two people.

What mistake do buyers make shopping compact microwaves?

The mistake buyers make is shopping by cubic feet instead of exterior fit. The Frigidaire and the Toshiba publish identical 13.6 x 19.6 x 24.4 in dimensions and identical 2.2 cu. ft. capacity, yet one installs into cabinetry and one sits on a counter. Capacity ranges from 1.1 to 2.2 cu. ft. here. Fit is what varies meaningfully.

Start with a tape measure, not a shopping cart. Write down the width, depth and height of the opening you intend to fill, then compare those three numbers against the two published cutouts in this guide. If the Frigidaire's 24 3/4 x 20 x 16 3/4 in requirement matches what you measured, order it and the matching trim kit together so the install finishes in one afternoon. That's the whole argument for the GMBS3068BF: it's the one pick here whose listing tells you in advance whether it will fit.

Last updated: September 14, 2026. Product availability re-checked.

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