When to Book Flights: What Holds Up and What Doesn't
Published by FlyingWith3 min readSources checked
Airline and government rules change. Check your airline's current rules before you travel.
FlyingWith editorial team
How we check our sourcesQuick answer
No published rule makes a particular day cheaper to book. Book when a fare fits your budget and schedule. For eligible flights booked directly with an airline at least seven days ahead, check its U.S. 24-hour cancel-or-hold option.
Scope: General booking advice for any airline. FlyingWith doesn't track fares, so this guide gives no booking-window numbers. The only official rule quoted is the U.S. Department of Transportation 24-hour reservation requirement.
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Go straight to the part you need.
Popular advice says to book on a certain day or at a certain hour. Airlines set and change their fares themselves and don't publish a schedule you can time. What you can control is how flexible you are, how you watch prices, and whether you understand a ticket's rules before you pay.
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What changes by airline
- Whether the airline gives you a 24-hour free cancellation or a 24-hour hold (U.S. rules require one of the two)
- Change and cancellation terms on your fare
- Third-party booking terms: the U.S. 24-hour requirement does not apply to online travel agencies or other intermediaries
General advice: applies wherever you fly
The "best day to book" tip
There's no official or published rule that makes a particular day of the week, or time of day, cheaper for booking. Prices for the same flight can change, so treat any "best day" tip as unproven.
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General advice: applies wherever you fly
What you can control
If your dates or airports are flexible, compare a few options: prices on the same route can differ between days and between nearby airports. Many booking sites have a calendar or flexible-date view that makes this quicker.
Rather than searching over and over, set a price alert for the route you're watching, so you're notified when the price changes.
Official rules: United States (DOT)
The 24-hour rule
For tickets booked directly with an airline at least seven days before scheduled departure, U.S. Department of Transportation rules require either cancellation within 24 hours with a full refund and no penalty, or a hold at the quoted price for 24 hours without payment. Airlines do not have to offer both.
This requirement does not apply to online travel agencies or other third-party agents and does not require free changes, such as a different date or a corrected name. Read the airline policy or intermediary terms before paying.
General advice: applies wherever you fly
When to just book
If a fare fits your budget and the flight suits your schedule, booking is a reasonable choice; waiting for a lower price is a bet that may not pay off. Before you pay, read the fare rules: whether changes and cancellations are allowed, and what they cost.
General advice: applies wherever you fly
Mistake fares
Occasionally a fare is published at an obviously wrong price. It may not be honoured, so don't book non-refundable hotels or other plans around it until the ticket is issued and the airline has confirmed it.
Official sources
Rules and amounts change. Before you rely on anything marked as an official rule, check the source. These are the official pages we used.
- Refunds · U.S. Department of Transportation
- 14 CFR 259.5: Customer service plan (24-hour hold or cancellation) · Electronic Code of Federal Regulations (U.S.)
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