What is the difference between a chest freezer and an upright?

The orientation changes the physics, and that produces genuine differences in efficiency, capacity and usability.

Chest freezer. A horizontal box with a lid on top.

More energy efficient, and the reason is straightforward: cold air is denser than warm air and sinks. When you open a chest freezer, the cold air stays in the box. Opening an upright lets it pour out of the front and be replaced by warm room air, which must then be re-cooled.

Better temperature stability, which matters for long-term storage quality and means contents survive a power cut far longer — often a day or more if left closed.

More usable capacity for the same stated volume, since there are no shelves, drawers or door fittings taking space, and the insulation is distributed differently.

Usually cheaper to buy per litre.

Often manual defrost, which is more efficient but means periodic emptying and defrosting.

The disadvantages are practical rather than technical. Access is poor — reaching items at the bottom means removing what is above, and food genuinely gets lost for years at the bottom of a chest freezer. It also occupies a large footprint, which makes it a garage or utility appliance rather than a kitchen one.

Upright freezer. A vertical cabinet with a front door, shelves and drawers.

Far better organisation and access — you can see and reach everything, which in practice means less waste from forgotten food. That offsets some of the efficiency gap in real use.

Small footprint, and it fits kitchen layouts.

Usually frost-free, which removes defrosting entirely at the cost of somewhat higher energy use and a tendency to dry unwrapped food.

Less efficient and less stable, as above.

Which to choose: a chest for bulk long-term storage, a garage or outbuilding, and lowest running cost; an upright for everyday use, limited space and frequent access.

Garage placement needs a climate-class-rated model.