A mathematical model was developed to describe the radiative and convective thermal interactions between a newborn piglet and it’s surroundings. The model incorporates surface energy balances for each surface in the enclosure. The model was verified with results from a simulated creep area and from published calorimetric studies on newborn pigs. Mathematical results were all within 5.5% of the measured results from a simulated creep-area. Compared with published studies, the mathematical model over-predicts heat loss in high-demand environments and under predicts heat loss in low-demand environments.