Seasonal weights are implemented in Manitoba to minimize the pavement damage due to traffic loading in spring and to improve the productivity of the trucking industry during the winter. This paper presents the implication of early or late start and end of seasonal weights to the pavement’s service life. Several scenarios that could impact the life of the pavement during the implementation of seasonal weights were identified. The seasonal variation of pavement stiffness was determined from FWD data collected in different seasons from instrumented test sites. These stiffness values were used to estimate the critical strains in the pavement at different temperature conditions using mechanistic analysis assuming elastoplastic properties of the materials. The reduction in the life of the pavement when seasonal weights are not implemented on time was estimated using the Asphalt Institute, Miner’s Hypothesis and MEPDG models. The results indicate that significant reduction in the life of the asphalt pavement occur when spring restrictions are not implemented on time. The results of the study can be used to justify revision to the existing policy on SWR and WSW.