The internet can't agree on this one. Here's the actual science and the practical answer.
The Science
Fragrance degrades from three things: heat, light, and oxygen. A fridge eliminates heat and light, making it theoretically ideal for long-term storage. The cold temperature slows chemical reactions that break down fragrance molecules over time.
The Practical Reality
For most people, a cool dark drawer or closet is perfectly adequate. Fragrances stored this way last 3-5 years without noticeable degradation. The fridge is overkill unless you're storing vintage or expensive bottles for years.
When to Use the Fridge
If you live in a hot climate without air conditioning, fridge storage makes sense. If you're cellaring expensive niche fragrances for long-term collection, the fridge preserves them better. If you bought a backup bottle you won't open for a year+, fridge it.
When NOT to Use the Fridge
Don't fridge your daily driver. Pulling a cold bottle out of the fridge causes condensation, which can introduce water into the fragrance over time. Constantly cycling between cold and room temperature is worse than just storing at a stable room temperature. Pick one and commit.