There's a saying in traveler communities that "you must buy plane tickets early to get a good deal."

I used to believe that too. Every time I went to Korea, I would book my tickets 3 to 4 months in advance and bragged, "I booked early and got a good price."

But one day, I asked a colleague who was on the same flight, and he had bought his ticket for $200 less than I did, just 3 weeks before departure.

Frustrated, I looked into it and found that nowadays, airfare prices fluctuate like stocks. They move in real-time based on supply and demand.

Many people think that about a month before departure is the sweet spot. That's incorrect.

Various airfare analysis data shows that the lowest price range for international flights is generally 90 days before departure or 18 to 29 days before.

This means that prices can be cheaper not just a month before but also around those times.

Why is that? Think from the airline's perspective.

90 days before departure, they lower prices to fill seats. Once a certain number of seats are filled, they raise the prices.

Then, 2 to 3 weeks before departure, they adjust prices again to sell the remaining seats.

The difference between those who know this pattern and those who don't can lead to hundreds of dollars in savings.

When demand increases, prices go up; when it decreases, prices go down. It's not a guess; it's determined by algorithms.

Data also shows that booking on Sundays is often the cheapest.

The reason is simple. Business travelers book during the week.

On weekends, especially Sundays, there is less demand in the airline systems, so prices drop.

What about the day of departure? It's said that Thursday departures are relatively cheaper, but I believe that Friday departures are the cheapest for international flights.

Monday is naturally expensive because business travelers and weekend vacationers are all booking then.

July and August, December and January. These are the peak times when Koreans fly the most.

Summer vacations, winter breaks, and the holiday season. During these times, airfare prices skyrocket.

What I've learned is that moving when others aren't is the best strategy.

In March, May, October, and early November, flying to Korea during these off-peak times can save you 30-50% compared to peak season prices.

And honestly, it's much better to have fewer people around when you're in Korea.

Airfare comparison sites track cookies and search history. If you repeatedly search for the same route, they may subtly raise the prices shown.

The solution is to search in Google Chrome's incognito mode (Ctrl+Shift+N). Since cookies aren't stored, you can see fresh prices each time.

Ultimately, the most realistic advice is to check prices regularly starting 3 to 5 months before departure.

If you turn on price tracking in Google Flights, you'll get alerts when prices drop. Apps like Hopper are also good.

And one more thing. For popular routes like LAX to Incheon, booking a year in advance may not yield significant savings.

In summary, aim for 90 days before departure or 18 to 29 days before.

Book on Sundays and depart on Thursdays. Take advantage of off-peak times. And start tracking prices 3 to 5 months in advance.

In the end, it seems that saving money is more about having information than just being diligent.