I am looking at prices for one way tickets from London to Los Angeles for this coming August. How far in advance should I purchase these tickets? The cheapest on Kayak right now is through Turkish Airlines around $750-$850, but it has a stop in Istanbul. No other airline really comes close to this price ($1000-plus). I was wondering if this a deal to jump on or if other airlines' prices will come down. When would be the best time to purchase these tickets? I suppose I could also fly out of Paris, but I'm guessing London would generally be the cheaper ticket.