We calculate new electron cooling rates due to electron vibrational excitation of CO2 and CO and rotational excitation of CO. Our results are expressed as closed form analytic expressions that are both convenient for numerical calculations and valid over a wide range of electron and neutral temperatures. We fine that our cooling rates and their temperature dependences differ significantly from other calculations. For CO2, these differences are related mainly to the assumptions about the approach to equilibrium and not to the actual cross-section choices. For electron temperatures below 1000¿K and gas temperatures near 300¿K (representative of conditions in the Venus atmosphere, where collisional cooling of the electrons dominates) our CO2 cooling rate is as much as an order of magnitude larger than previously considered in ionospheric models.