Fly & Buy Planner
Plan a flight · any two airports

When to fly, when to buy

Type where you're going and when. You get a buy-now-or-wait call, the cheapest times of day to fly, and searches on Google Flights and United set up for your dates.

Example trip filled in. Type your own airports (code or city) and dates.

Buy now or wait?

  1. On Google Flights, look under the results for the price rating. Low or typical means it's a fair time to book.
  2. Tap Date grid to see the same trip a few days earlier or later. Moving a day often saves more than any other trick.
  3. Tap Times and choose an early-morning departure to see if the first flight of the day is cheaper on your route.
  4. Turn on Track prices to get an email when the fare drops.
  5. Before paying, open the same flight on the airline's own site. On our Newark–St. Louis check, Google and United showed the same price 92% of the time.

Best times to fly

When fares are usually lowest

Days before departure when prices tend to bottom out, by where you're flying. Your trip's row is highlighted.

TripDays beforeSource

Where this advice comes from

Booking windows: Google Flights fare analysis (2022), Google Flights holiday and Europe trends (2023), and CheapAir's airfare study (2017) for regions Google didn't cover.

Days of the week and months: Expedia 2026 Air Hacks report and the Google Flights analysis above.

Time of day: a check of 60 Newark–St. Louis round trips on Google Flights and United.com on Oct 26, 2026. That's one route, so use the Times filter to confirm yours.

Bags: United baggage allowance summary. The studies are averages from U.S. travel. Your route can behave differently, and Google's price rating for your exact dates is the best single signal.