SiaFDM21SI

Freestanding
Solo Microwave
Turntable

£55Typical price

Test score

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Sia’s FDM21SI freestanding solo microwave is at the cheaper end of microwaves we’ve tested, plus its two-year guarantee should provide some reassurance. However, it’s only a bargain if it’s quiet, user-friendly and great at cooking and defrosting – read our full review to see if it’s really a steal.

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cons

What's included?

What is it?
How well does it warm up food?
How well does it defrost food?
How easy is it to use and clean?
Is there anything else I should know?
Should I buy it?

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KEY TEST RESULTS
Single use
Manual Defrost
Ease of use

May 2025First reviewed by Which?
Jan 2025Released

The overall Which? test score is made up of the following star ratings, all determined by our rigorous lab tests.

Row of white microwaves on display in a store, with labels beneath each appliance and a blurred background.

How we test microwaves

14 Oct 2025

Single use

How we test single use

We test how quickly and evenly microwaves heat in microwave mode and we record how much water is lost from the food during cooking. This is the overall score for microwaves heating one dish, from cold, in microwave mode.

Speed of heating

How we test speed of heating

We test how quickly the microwaves can heat up when cooking in microwave mode.

Evenness of heating

How we test evenness of heating

We check for hot and cold spots in food to make sure it's evenly cooked.

Quality of food

How we test quality of food

We test how much water is lost from food when heating in microwave mode.

Continuous use

How we test continuous use

This is the overall score for microwave heating when the microwave has previously been in use and has warmed up. We test how quickly and evenly microwaves heat in microwave mode and we record how much water is lost from the food during cooking.

Manual Defrost

How we test manual defrost

How evenly the microwaves defrost minced meat on a manual setting.

Auto Defrost

How we test auto defrost

How well the microwave defrosts using its automatic defrost program.

Steaming

How we test steaming

How well the microwave steams a meal of fish, potatoes and veg.

Ease of use

How we test ease of use

This includes setting the clock, opening and closing the door, loading and unloading the oven, using the power and time controls, reading the display, cleaning, and the instructions and information provided by the manufacturer.

Cleaning

How we test cleaning

How easy it is to clean inside the microwave and the exterior casing.

Quietness

How we test quietness

We test how noisy each microwave is in microwave heating and defrosting mode.

Energy consumption single use

How we test energy consumption single use

How much energy is used by the microwave to heat food when it is only used once.

Energy consumption repeated use

How we test energy consumption repeated use

How much energy is used by the microwave to heat food when it is being used in quick succession.

General
Type	Solo Microwave
Freestanding or built-in	Freestanding
Turntable or flatbed	Turntable
Height	26.1cm
Width	45.8cm
Depth	35.3cm
Max plate size	27cm
Type of controls	Buttons, dial

Power
Stated Microwave Power (watts)	700
Number of power levels	5

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SiaFDM21SI