We do not have enough data on this route to provide a reliable graph showing how many days before departure it is the best to book.
However, usually the closer it is to the departure, the more expensive the tickets are.
The most popular airlines on the route Las Vegas McCarran - Boston Edward L. Logan: United Airlines (UA), American Airlines (AA), Spirit Airlines (NK).
Direct flights last about 4h 57min.
Direct flights available 2 days a week - Thursday, Friday.
Direct flights: Spirit Airlines (NK), American Airlines (AA), JetBlue (B6).
Las Vegas (NV) Boston (MA)