Don't burn citronella candles indoors.

No, they’re not safe to burn inside.

Citronella candles are designed for outdoor use. The active compounds (citronellal, geraniol) are meant to disperse in open air to repel mosquitoes. Indoors, those same compounds concentrate fast — they can irritate your lungs, trigger headaches, and leave a greasy soot on your walls. Most manufacturers flat-out warn against indoor use on the label.

Some people think “natural” means harmless, but concentrated essential oils in a small room aren’t the same as a breeze. Plus, the smoke from any candle adds to indoor air pollution. If you want bug repellent indoors, try a fan or a plug-in diffuser designed for the space.

Stick to regular beeswax or soy candles inside. Save the citronella for the patio.