When to go to Berlin for the best price
The cheapest months for a Paris-Berlin flight are November, January and February outside school holidays, with returns often under €70. Spring and autumn (May-June, September-October) give the best weather-to-price ratio.
Avoid December because of Christmas markets (hotel prices +30%) and late July to mid-August, as well as German long weekends when hotels sell out. Book your flight 4 to 7 weeks ahead for a city break; Tuesday and Wednesday departures are often 20% cheaper than Friday evening.