While debated, many travelers still prefer searching in private windows to ensure site cookies aren't triggering price hikes based on repeated searches.
To truly find the lowest fare, rely on tools rather than traditions:
While the day you buy matters less, the day you matters immensely. Mid-week departures (Tuesdays and Wednesdays) are consistently the cheapest because they avoid the rush of business travelers on Mondays and vacationers on Fridays and Sundays. Shifting your itinerary by just 24 hours can often save hundreds of dollars. Practical Strategies
In short, don't wait for a specific Tuesday to hit "purchase." Instead, monitor the price trends for your specific route and be ready to jump when the data shows a dip.
No matter what day you book, flying during "shoulder seasons" (like late April or September) will almost always beat prices found during peak summer or holiday periods.