Being a spontaneous soul is a fantastic way to see the world, but it isn't necessarily the wisest way to land a bargain airfare. Think about booking your Borispol Intl. Airport (KBP) to KGO trip ahead of time rather than waiting till the last minute. Based on flight pricing and demand studies in 2022, we have found that the best time to book domestic flights is between 28 – 35 days ahead of the departure date, and international flights three to four months in advance. Save all that spontaneity for when you arrive in KGO!