That's the lowest price we could find for select fares on a comparable 4-star carrier by $55. Plus, if you need to alter your vacation plans, change fees are waived for travel through September 30. Buy Now at DealBase Tips On the DealBase landing page, click on "Aer Lingus" in the top line to see this sale. We found this price on flights departing on September 22 from Philadelphia, PA (PHL) to Dublin, Ireland (DUB), with return on September 29. Of note, if you're scheduled to fly before September 30, you can change the date of your trip with no change fee, although a fare difference may apply. All prices, dates, and booking details were valid at the time of publication. Book this travel deal by September 1 for flights from September 1 through October 31.