Travelers have found it’s best to book a flight 21 days in advance to save up to 13% compared to booking the same week of travel. As your travel date approaches, the cost of this flight route may potentially increase. While opting to book 21 days out may not be an option for all, there are still additional ways to secure a deal in the near future. You might find a flight from Islip to Pennsylvania 1-2 weeks in advance for as low as $213, or $252 for flights within the next 24 hours.
Flights from Islip to Pennsylvania lean towards being more expensive in December. Prices are generally better when you fly from Islip to Pennsylvania in February, with the cheapest ticket starting at $102.