The best time to book a vacation package to Paris is typically during the shoulder seasons, which are in the spring (April to June) and fall (September to November). During these times, the weather is generally pleasant, the crowds are smaller, and prices are lower for accommodations and flights. Avoid booking during the peak summer months and major holidays, as these times will not only be more expensive, but also more crowded and less enjoyable. Additionally, booking well in advance or taking advantage of last-minute deals can help you find the best prices for your vacation package. When booking a vacation package to Paris, consider the activities and events you want to experience. For example, if you want to attend fashion week in Paris, then booking during the corresponding months is crucial. In conclusion, the best time to book a vacation package to Paris is during the shoulder seasons, while avoiding peak tourist times and keeping an eye out for deals and discounts.