According to some embodiments, a capillary tube may be utilized to facilitate bubble containment in liquid cooling systems. For example, a system may comprise a first volume to contain a liquid, a second volume to contain the liquid and a gas, a capillary tube configured to hydraulically couple the first and second volumes, an inlet coupled to the first volume to receive the liquid from an electronics cooling system, and an outlet coupled to the first volume to provide the liquid to the electronics cooling system.