Should I freeze coffee beans?

Freezing is genuinely effective and almost always explained badly, which is why it has a mixed reputation.

What works

Whole beans, divided into portions of a few days each, in genuinely airtight containers, frozen once.

To use a portion: take it out and let it come fully to room temperature before opening it. Then use it within a few days as normal.

Done this way, freezing arrests staling almost completely. Beans frozen at two weeks old and thawed three months later taste close to how they did going in. There is also evidence that very cold beans grind slightly more uniformly, though that is a smaller effect.

What ruins it

Opening the same bag in the freezer repeatedly. Every time you take a cold bag out, moisture in the room condenses on the beans. Moisture is the fastest way to destroy coffee, and doing it daily is worse than not freezing at all.

Thawing before opening is the whole trick. Condensation forms on the outside of a sealed container instead of on the coffee.

Freezing ground coffee — pointless. The aromatics are already going and freezing does not bring them back.

The fridge, meanwhile

The fridge is the worst of both worlds: not cold enough to arrest staling meaningfully, humid, and full of smells that coffee readily absorbs. Do not use it.

When freezing is worth the bother

If you buy a lot at once, or buy an expensive competition lot you want to spread over months, or find a coffee you love and want to keep. For a 250 g bag you will finish in a fortnight, it is unnecessary — buy less, more often.