Question : Do travelers from Chicago typically stay in London for very long?
Answer : Of course you're not most people, but if you were, you'd stay roughly 12 days.
Question : If your plans are flexible, have you considered changing your departure day?
Answer : For the month of December, the cheapest day to fly is Sunday. Being flexible with your travel days garners you even more savings during your booking.
Question : Are prices changing frequently for this route?
Answer : Prices for this trip tend to fluctuate a lot more than others. However, the sooner you book, the better price you tend to get.