Airfare prices change constantly, fueling plenty of myths about the best time to book and how to find the lowest fares. Scott Keyes, founder of Going — a travel app formerly known as Scott’s Cheap Flights that sends out airfare deal alerts — has heard them all.

“You’ve heard the advice to book on Tuesday at 1 p.m., or Saturday at midnight, or exactly 63 days before,” Keyes said in an episode of NerdWallet’s Smart Travel podcast. “The fact that there are so many different rules about when you’re supposed to book should kind of be the tip-off that it’s a little bit of a myth.”

While there is no golden rule, Keyes does have six tips and takeaways from over a decade as a professional flight deal finder.

1. There is no ‘best day’ to book a flight

Keyes says the best time to book a flight isn’t so much tied to a specific time or day, but rather how many months in advance you make your purchase. He recommends booking within what he calls the “Goldilocks window.”

“It’s not too early, not too late, but just right in the middle,” he said, describing this ideal booking time.

Here’s the Goldilocks window for each type of flight:

• Domestic flights (off-peak): 1 to 3 months in advance.

• Domestic flights (peak seasons like summer or Christmas): 3 to 6 months in advance.

• International flights (off-peak): 2 to 8 months in advance.

• International flights (peak seasons): 4 to 10 months in advance.

2. Incognito mode won’t help you find cheaper flights

Some people believe that airlines are “watching” your computer usage by way of cookies, which track how you interact with websites, and using this data to charge higher fares to those who search repeatedly for flights.

Keyes says these theories don’t make sense though — especially given his line of work.

“If airfare prices changed based on repeated searches, we’d see it because we track millions of airfares every single day,” he said. “If somebody was going to see higher flight prices impacted by repeated searches, it would be us. Yet we don’t.”

3. Don’t count out budget airlines

Budget airlines like Frontier Airlines and Spirit Airlines are known for charging fees for carry-on bags and other services. But their ultra-low base fares could help some travelers spend less.

“If you’re traveling with just a backpack, budget airlines can absolutely save you money,” he said. “I’ve looked at flights from my home airport in Portland down to Las Vegas, and the Spirit flight cost $25 each way when the next-closest Alaska Airlines flight costs $130.”

And you might be surprised at the convenient routing options on budget airlines, too.

“Especially to destinations like Las Vegas and Orlando, budget airlines actually have the most nonstop flights,” Keyes said. “If you’re flying from say, Minneapolis or Des Moines, Iowa, you actually might be able to get a nonstop flight on a budget airline.”

Just be aware of the extra fees for things that are often included in other airlines, such as carry-on bags and even an in-flight beverage. Once you add up those costs, the total price can sometimes be more expensive than full-service airlines.

4. Know your back-up options

Avoiding layovers when possible (especially if it involves saving money) can reduce travel time and also mitigate the risk of snowballing delays.

If you book a flight with a layover, find out what your alternative flight options might be if a delay makes you miss your connecting flights. You should aim to fly with airlines that have multiple flights a day to your destination from the connecting airport.

“If you’ve got a flight on Spirit and that flight gets canceled, it might be a while until there’s the next available Spirit flight to your destination,” Keyes said. “They don’t have partnerships with other airlines to put you on a different carrier, so you could actually be waiting sometimes days to get a replacement flight. That’s something that usually doesn’t happen if you’re on Delta Air Lines or United Airlines.”

5. Don’t hesitate when you find a great fare

One thing Keyes has learned over the years: Airfare deals don’t stick around for long. It’s important to act fast, he notes, or they can slip away.

“I once found a deal to India for $212 round trip,” he said. “My heart skipped a beat. I had sweaty palms. I was so excited. But instead of booking it immediately, I spent a couple of hours figuring out my itinerary. When I went to book, I missed it by 30 seconds.”

The lesson?

“Book first, ask questions later,” he said.

In the U.S., federal regulations make it easier to get a refund if you change your mind after booking. Under the 24-hour rule, airlines are required to refund your money to the original form of payment if you cancel within 24 hours of purchasing that airfare.

6. Book to prioritize price

“Most people say they want cheap flights, but they go about finding them in the exact opposite way,” Keyes said. Rather than looking at prices first, he added, they look at destinations and dates first.

He suggests flipping the process:

• Start with price: Identify the cheapest flights available.

• Pick your destination: Choose from the available deals.

• Select your dates: Work within the cheapest available timeframes.

“What I tell folks is like, ‘Look, if cheap flights are a priority, make them the priority,’” he said. “By setting price as the last priority, we end up with some pretty expensive flights.”

Seasons of savings

Airlines are gearing up for their busy summer schedules, flying to new destinations and increasing frequencies to popular cities. They’re even starting to announce new fall routes.

For airfare deal hunters, that means new opportunities to travel somewhere for cheap. New flights are worth tracking, especially when airlines offer attractive deals to market their route announcements.

“This is really an opportunity where the airlines can make a grand entrance for a new route and really drum up excitement,” says Katy Nastro, a spokesperson for Going, a flight deals alert service.

Here’s how travelers can take advantage of new routes and the deals surrounding them.

Keep lookout for introductory fares

Summer schedules have been released for a while, and some carriers are already thinking ahead to fall. Delta has announced that it was launching flights from Atlanta to Marrakech, Morocco, in October 2025. (United Airlines started flying to Marrakech from Newark Liberty International Airport, its New York area hub, last year.)

Delta’s fall flights to Marrakech have been on sale for as low as $534 round trip. That’s well below the average price of about $950 for an itinerary that, up until now, has included connections, according to Going.

Keep an eye out as new flights or destinations are announced. If you are flexible about where to travel this year, you might be able to snag a cash or points discount as part of a new route promotion.

Budget carriers like Spirit Airlines and Frontier Airlines have also announced updates to their route networks. Earlier this month, Spirit announced it was adding service to Chattanooga, Tennessee, and Columbia, South Carolina — moves that could help bring down airfares for these markets.

However, introductory fares are not necessarily the best deals. Use travel search tools to find out what have historically been considered cheap prices for a specific route.

Consider the competition

Sometimes, airlines launch new routes where they’re competing with incumbent carriers. That happened last summer when Delta started flying from Seattle to Taipei, Taiwan, which was already serviced by EVA Air, a Taiwanese carrier. Within months, two other Taiwanese carriers — China Airlines and Starlux Airlines — also launched flights to Seattle from Taipei.

To put that in perspective, in July 2023, there were 10,602 airplane seats available on that route, according to Cirium, an aviation analytics company. This July, that number is expected to quadruple to a whopping 43,222 seats.

When so many seats flood the market like that, airlines often respond by dropping prices to undercut the competition. The price war for this summer has already begun, with Delta pricing round-trip flights in early July for as low as $740 in the last 60 days, according to Google Flights. Other airlines have been asking around $1,300 or more per person, nearly twice as much.

Taipei has also featured prominently in Delta’s award sales. Last month, points and miles travelers could book round-trip economy tickets to Taipei from Seattle and other West Coast cities for 40,000 Delta SkyMiles plus taxes and fees.

More competition can also lead to lower prices on domestic flights.

Take flights between Seattle-Tacoma International Airport and Ronald Reagan Washington National Airport, for instance. Alaska Airlines was the only one flying that route nonstop until this month, when Delta launched its own flights. Now, two carriers are competing for passengers. Watch this route for potential fare drops.

Sometimes, just wait it out

If you missed the introductory deals that came out months in advance, you still might get lucky.

New routes can also lead to lower prices when carriers overestimate the demand for a certain destination. “Airlines can only forecast so well,” Nastro says, so when anticipated demand doesn’t materialize, “later-in-the-game softening” might lead to good deals.

One airline to watch this year is United. This summer, the carrier is adding flights to far-flung locales like Ulaanbaatar, Mongolia, and Nuuk, Greenland — obscure destinations that surprised many when they were announced.

United is betting big that travelers are tiring of overcrowded tourist destinations and would rather visit places off the beaten track. How full those new flights get will determine how airfare pricing looks toward the end of the season on its new routes — and whether they return next year.

How to take advantage of new airline routes

Sign up for emails from your favorite airline. Airlines will typically send new flight route deals to their email lists. Typically, only a select number of seats go on sale, so it pays to be among the first to know.

Use tools like “Explore” on Google Flights. Those results will show you the cheapest flights to anywhere in the world for the dates you select, and you might find destinations that you didn’t even know you could get to from your home airport.

Use tools that track pricing history to help provide a benchmark for what is actually a good deal. Google Flights and Going both offer such features. Set up price alerts and book a fare that lets you rebook and get a flight credit if the price drops.