There is reasonable anecdotal evidence that backs up the use of chemical and audio repellents, but also equally credible evidence of foxes ignoring them with little to no effort. It’s likely that a fox’s drive to sustain itself overrides its aversion to any strong smelling materials or irritating noises, but if you’re not getting the results you want, they don’t cost much money to install. Another device that has had varied success for deterring foxes is an automated sprinkler. These devices are activated when the sensors detect movement, spraying the fox with a jet of water to frighten it away.

Foxes are famously cunning, so short of completely fortifying your premises, you’re unlikely to guarantee a fox-free yard 100% of the time. However, taking away the points of attraction goes a long way, and if a fox sees nothing in your yard worth getting there’s less chance it will bother returning.