How long is a flight from Boston to Puerto Rico The duration of a flight from Boston to Puerto Rico typically ranges from approximately 4 to 5 hours. However, the exact flight time may vary based on factors such as the departure and arrival airports, layovers, and prevailing weather conditions. Non-stop flights tend to be on the shorter end of this range, while those with layovers can extend the journey. Passengers can expect a relatively convenient and efficient travel experience when flying between Boston and this beautiful Caribbean destination.