What smell will keep mice away?

Mice have a very sensitive sense of smell and dislike certain strong, pungent odors, but it is important to understand that smell alone will not permanently keep mice away if food and shelter remain. The most commonly cited smell that deters mice is peppermint oil, with its strong menthol scent that overwhelms their noses, often applied to cotton balls placed near entry points, behind appliances, and in attics, though it evaporates quickly and needs frequent reapplication. Other smells mice dislike include cloves, cayenne pepper, eucalyptus oil, vinegar, ammonia which mimics predator urine, and the scent of predator urine itself like fox or cat urine available from garden stores. Some people use dryer sheets, but evidence for them is weak. While these smells may cause mice to avoid a specific small area for a day or two, hungry mice will often tolerate the smell if there is food nearby, and they quickly habituate. Pest control professionals consider scent repellents as a minor supplemental measure, not a primary control method. The only reliable way to keep mice away long term is to seal all holes larger than a quarter inch with steel wool and caulk, store all food in airtight glass or metal containers, fix leaks, remove clutter, and use traps or professional exclusion services.