Methods, systems, apparatus, and articles of manufacture to cool integrated circuit packages having glass substrates are disclosed. An example glass core of an integrated circuit (IC) package disclosed herein includes a fluid inlet to receive a cooling fluid, a fluid outlet, and a channel to fluidly couple the fluid inlet to the fluid outlet, the cooling fluid to flow through the channel from the fluid inlet to the fluid outlet, the channel fluidly isolated from one or more vias extending between a first surface and a second surface of the glass core.