Citronella oil lasts 1-2 years, maybe more.

About 1-2 years if stored properly.

Essential oils don’t really “go bad” in a spoilage sense, but they oxidize over time. Citronella is a citrus-based oil with citronellal and geraniol — those compounds break down when exposed to light, heat, and air. After a year or two, it’ll still smell like citronella, but it loses potency. That means it won’t repel bugs as well.

Keep it in a dark glass bottle, away from sunlight, and screw the cap on tight. Refrigeration can extend the life a bit, but not by much. If it smells like old paint or varnish, it’s oxidized past the point of being useful.

But if it smells off, toss it.