United Roundtrip Nonstop Flight: Washington, DC (IAD) to/from Las Vegas, NV (LAS) $157 (Travel July to Aug, 2025)

United Airlines and Expedia have round trip airfares travelling to and from Las Vegas (LAS) and Washington DC (IAD) for $157 nonstop. These are basic economy fares. On United, you may only have a personal item. There is no seat selection and no change. If you are travelling with children, you will be seated together as per each airline's policy. Travel Availability: Departs IAD: July 1-2, 7-9, 12-16, 19-23, 26-30; Aug 2-5 Departs LAS: July 1-2, 4, 8-12, 15-19, 22-26, 29-31; Aug 1-2, 5