Most travellers find the cheapest return flights to Berlin when choosing a flight departing in January.
On average, from most locations, when planning your trip to Berlin, try to book your flight in the region of 60 days in advance for the cheapest prices.
From most locations, the cheapest flights to Berlin are found on a Monday. Booking a Saturday departure is usually the most expensive.
On average you can find the best deals on plane tickets to Berlin when looking for flights with midday departure times.