<p>The concept of residence time of energy in a planetary atmosphere τ<sub><i>R</i></sub>, recently introduced and computed for the Earth's atmosphere (Osácar et al., 2020), is here extended to the atmospheres of Venus, Mars and Titan. After a global thermal perturbation, τ<sub><i>R</i></sub> is the time scale the atmosphere needs to return to equilibrium. The residence times of energy in the atmospheres of Venus, Earth, Mars and Titan have been computed. In the cases of Venus, Mars and Titan, these are mere lower bounds due to a lack of some energy data.</p>