Onychomycosis, also known as tinea unguium, is a fungal infection of the nail bed or nail plate. It affects approximately 14% of the world's population and accounts for approximately 50% of all nail diseases. Dermatophytes, non-dermatophyte moulds, and yeast are the most common causative organism. It was initially thought to be a cosmetic issue but has recently gained attention due to its persistent nature and difficult treatment with relapses. Onychomycosis is typically treated with oral and topical medications. Although effective, oral antifungal agents are hepatotoxic and cause drug-drug interactions. Topical therapy is more patient-friendly because it does not have these side effects, but it has another disadvantage of improper nail penetration. Efforts have been made for decades to improve topical delivery for the effective treatment of onychomycosis. Mechanical, physical, and chemical methods were used. Despite all efforts, the nail delivery problem remains unresolved. For improved drug permeation and localized therapy, the emphasis has recently shifted to novel drug delivery systems such as nanoparticles, microemulsions, polymeric films, and nail lacquers. This review article discusses both conventional and novel formulation approaches for the treatment of onychomycosis.