<p>This comprehensive review explores electroless cobalt deposition, an appealing surface modification technique that offers advantages such as uniform coverage on complex geometries and compatibility with diverse substrate materials without external power. The article systematically examines the critical impact of various bath constituents and operational variables on the characteristics of deposited films. It details the roles of the cobalt source, different reducing agents, complexing agents, pH regulators, and stabilizers. Additionally, the article scrutinizes the influence of deposition parameters like temperature, solution pH, agitation methods, and bath aging. The formation of numerous cobalt-based alloys and composite materials are also discussed. This review aims to guide the development of optimized electroless cobalt plating solutions, highlighting their wide-ranging utility in fields such as microelectronics, data storage, protective coatings, electrolytic green H₂ generation, metal matrix composites, and electromagnetic shielding, thereby fostering advancements in intricate material fabrication.</p>