American Airlines, United, jetBlue, and Delta have round-trip flights from Atlanta (ATL) to Philadelphia (PHL, IAH, DFW, MCO, ORD, EWR/LGA/JFK) for $138, NONSTOP. Most flights are between September to March, but New York is limited to September thru November. Extended weekends available. Origin/Destination reversible.
Carrier will depend on Destination, New York is via jetBlue or United, other destinations are via American or Delta.
A Carry-on bag and also a personal item is allowed for free on Delta and American. You can avoid paying for seat selection by accepting the randomly assigned seat at the gate.
Click for more details and booking links Nonstop Flights: Atlanta to/from Philadelphia, Houston, Dallas, Orlando, Chicago, or New York $138 r/t [September-March] – American Airlines / Delta / United / jetBlue