The answer to 'extermination season' is that there is no single 'extermination season' - pests can be active and require treatment year-round, depending on the specific pest and your location. However, there are typically busier seasons for pest control services.
Many common household pests like ants, cockroaches, and rodents tend to be more active and visible in the warmer spring and summer months as they seek food, water, and shelter. This can lead to an increase in pest control service calls during this time. Cooler fall and winter months may see a slowdown in some pest activity, but other pests like mice and rats may become more problematic as they look to move indoors to escape the cold.