An antimicrobial catheter assembly can include a hub, a catheter tube connected to the hub, at least one extension leg connected to the hub, and a non-eluting antimicrobial coating on an internal or external surface of the catheter assembly. The hub includes at least one hub lumen defining a corresponding hub portion of a fluid pathway through the catheter assembly. The catheter tube includes at least one catheter-tube lumen defining a corresponding catheter-tube portion of the fluid pathway through the catheter assembly. The extension leg can include an extension-leg lumen defining a corresponding extension-leg portion of the fluid pathway through the catheter assembly. The antimicrobial coating can include a copper-based layer between a corrosion-preventing layer and the internal or external surface of the catheter assembly, an adhesion-promoting layer between the copper-based layer and the internal or external surface of the catheter assembly, or a combination thereof.