Background: Universal adhesives revolutionized restorative dentistry by enabling clinicians to employ a single material in self-etch, etch-and-rinse, or selective enamel-etch modes. However, their efficacy is dependent on the stability of whole formulations that incorporate water, volatile organic solvents, acidic functional monomers, hydrophilic resins and photoinitiators. Storage temperature can affect viscosity, solvent evaporation, monomer mobility, phase stability, and polymerization, which may influence the quality and durability of the resin–dentin contact. Objective: This narrative review explored the influence of refrigerated storage, room-temperature storage, prolonged heat exposure, and short-term prewarming on the bonding performance of universal dental adhesives. Results: Available evidence indicates that temperature effects are strongly formulation dependent. Refrigeration may reduce chemical deterioration and preserve volatile components, although adhesives used immediately after removal from cold storage may exhibit increased viscosity, reduced dentin wetting, and slower solvent evaporation. Controlled prewarming may improve flow, monomer diffusion, and solvent removal in selected formulations, whereas prolonged exposure to elevated temperatures may accelerate solvent loss and destabilize reactive components. Artificial aging decreases bond strength and increases interfacial permeability. Differences among studies are attributable to variations in solvent systems, functional monomers, water content, storage duration, application protocols, and testing methods. Conclusion: No single storage temperature can be recommended for all universal adhesives. Clinicians should follow product specific instructions, avoid prolonged thermal exposure, allow refrigerated materials to reach the recommended working temperature, and ensure adequate active application, air thinning, and light curing.