Biologic drugs have revolutionized the treatment of psoriasis and other chronic inflammatory diseases. In recent years, many tumor necrosis factor-alpha 'biosimilar' agents have been developed. These biosimilars are similar in structure and function to their originator molecules, although they are not identical. Given that the safety and efficacy of the original biologic have already been proven, biosimilars are only required to show bioequivalence, or non-inferiority, to the reference biologic to be approved. Based on extrapolation of these non-inferiority data, biosimilars may be subsequently approved for all indications of the originator biologic, even without being directly studied in these various conditions. These biosimilar agents have been purported as a method to reduce the costs of biologic therapies, thereby increasing the accessibility of these medications and subsequently improving the treatment of psoriasis worldwide. The US Food and Drug Administration and/or the European Medicines Agency have approved biosimilars of adalimumab (Amjevita/Amgevita/Solymbic, Cyltezo, Imraldi/Hadlima, Hyrimoz/Hefiya/Halimatoz, Idacio, Hulio, Abrilada), etanercept (Erelzi, Benepali/Eticovo), and infliximab (Inflectra/Remsima, Renflexis/Flixabi, Ixifi/Zessly) for the treatment of psoriasis, and others are under review. There are many phase III data supporting the bioequivalence of these anti-tumor necrosis factor-alpha biosimilar agents in treating psoriasis and rheumatologic disease, which are discussed here. In general, these biosimilar agents have been shown to have equivalent efficacy, tolerability, and immunogenicity profiles compared to their originators in patients with rheumatologic disease, although studies in patients with psoriasis are fairly limited. Additional switching studies and post-marketing safety analyses are needed to assess the interchangeability of biosimilar agents with their reference products.