Maybe you're looking to book a flight over the long Thanksgiving weekend or during the winter holidays. Maybe you want to travel to Europe during shoulder season. Whatever your travel plans, as you look over flight schedules, you may be wondering: When are the best days to book a cheap flight? Is it cheaper to purchase far in advance or wait till you're closer to your travel dates?

Right on time, Google Flights just released its key insights on 2024 travel data and trends, including answers to those questions above. Flights and their related prices are constantly in flux, Google aggregated four years of airfare data and trends to provide US travelers an overarching guide to how to get the cheapest flights possible and the best times of the year to fly. 

Read more: Use Your iPhone to Easily Monitor Flight Delays and Cancellations

When is the cheapest day of the week to fly?

If you're planning to book a flight, especially around the busy holiday season, you are likely trying to find the most budget-friendly option. According to Google Flights, the cheapest flights are available when flying on Monday, Tuesday and Wednesday, with Tuesday being the cheapest day, according to the historical flight data. Flying early- to mid-week can save travelers 13 to 20% on airfare compared to flying on Friday, Saturday or Sunday, with Sunday as the most expensive day to fly. 

Do layovers really save money?

It may come as no surprise that flights with layovers are cheaper than nonstop flights, but you may not realize just how significant those savings can be. The Google Flight data shows that travelers can save 25% by booking a flight with a layover instead of a nonstop flight.

Is there a best day of the week to book flights?

While there are certainly cheaper days to fly, there aren't really cheaper days to book. "There's not much benefit to buying your tickets on a certain day of the week," according to the Google report.

Google Flights does state that Tuesdays are typically the cheapest day of the week to book, according to the data, but Tuesday bookings are only 1.3% cheaper than the most expensive day, Sunday.

Is it cheaper to book flights far in advance?

To wait or not to wait? According to Google, it's better to book your travel far in advance, especially if you need to fly on a specific day or time. However, there are some patterns you can analyze to decide whether it's better to wait for lower prices or book now based on specific scenarios, destinations and dates of travel. 

For domestic flights, the prices are generally at their lowest between 21 and 52 days before your trip -- with 38 days before departure being the cheapest day to book on average. 

For international flights, the prices are generally lowest between 50 and 101 days before your trip, but it's generally best practice to book as early as you can. According to Google, "average prices don't meaningfully drop anytime before departure, but they usually do start to rise within 50 days of the flight itself" when it comes to international travel from the US. 

When is the best time to book a flight in every season?

Here's what Google says about the best times to book holiday flights and vacation trips to certain popular destinations. 

Thanksgiving: The cheapest domestic flights over the Thanksgiving holiday are usually available between 26 to 59 days in advance, with 45 days out being the cheapest -- meaning it's best to book Thanksgiving flights in early October. 

Christmas: The cheapest domestic flights over the winter holidays are usually available between 36 to 72 days in advance, with 58 days out being the cheapest. It's best to book Christmas or holiday travel in the latter half of October. 

Summer break: The cheapest domestic flights in July and August are usually available 13 to 43 days in advance, with 21 days before departure being the cheapest day on average to book. 

Spring break: The cheapest domestic flights in March and April are available between 33 to 59 days in advance, with 44 days before departure being the cheapest time to book on average. 

When is the best time to book a flight to Europe?

International flights to Europe from the US are usually cheaper 50 or more days before departure, with 94 days out being the cheapest day to book on average. As with all international travel, it's generally best practice to book as early as you can.

When is the best time to book a flight to Mexico or the Caribbean?

International flights to Mexico and the Caribbean are the one exception to the broader international trend, according to Google. That's because flights are generally at their lowest between 26 and 68 days in advance, with 44 days out being the cheapest.

What are the top destinations for holiday travel?

Google also released insights on the top-searched destinations for each holiday. 

Thanksgiving: The top-searched destinations for trips departing between the dates of Nov. 24 through Dec. 1 include Orlando, Florida; Cancun, Mexico; New York; Tokyo; London and more.

Christmas and New Year's Eve: The top-searched destinations for trips departing between the dates of Dec. 22 through Jan. 5 include Tokyo; Orlando, Florida; Cancun, Mexico; Miami; New York and more. 

For more, check out CNET's picks for the best travel credit cards in 2024. You can also explore the 12 travel essentials you always need to pack and the worst airlines for flight delays and cancellations.