For travel in 2026, the "sweet spot" for booking a flight from the US to Italy is typically 2 to 4 months in advance. For peak summer departures (June–August), you should aim for the earlier side of that window, booking between January and March. Booking too early (more than 10 months out) often results in paying "advance-purchase premiums" as airlines haven't yet released their most competitive fare buckets. Conversely, waiting until the last 30 days usually leads to significantly higher prices as you compete with business travelers and procrastinators. If you are looking for the absolute lowest fares, consider the "shoulder seasons" of May or September, where you can often find deals $300--$500 cheaper than mid-July. Always use tools like Google Flights to track prices and book as soon as you see a dip below the average "green" price for your specific route.