The best time of year to visit Belgium is in the summer when there is the best chance of nice weather.
Belgium has unpredictable weather all throughout the year, but generally follows a continental climate. Rain can be heavy throughout the year, so make sure to bring a jacket and umbrella whenever you visit.
Winter weather in Belgium is very cold, while spring and autumn are chilly but pleasant. Summers can be warm or hot, but again, rain is frequent.
If you don’t mind the cold or a bit more rain than usual, spring and autumn are good times to visit Belgium. There are fewer tourist crowds during these seasons, and prices can be lower outside of the peak summer holiday period.
You can take advantage of off-season deals on package tours to Belgium and hotels in Brussels, Bruges, and other Belgian cities if you travel during the late autumn, winter, or early spring. Winter hours for attractions can be short, though, so make sure to keep that in mind when deciding on when to visit Belgium.