Originally Posted by
mersk862
September 11 fee is $2.50 per segment up to 4 segments on the itinerary (so if you have a BOS-ATL-SLC-HNL-SLC-ATL-BOS trip, it's only $10).
When I've SDC'd, it's gone either way. Sometimes if I were to transit MEM, I'd get a small voucher back since their PFCs are pretty low.
MEM has no PFC at all. Most airports have a $4.50 PFC, with a few such as CVG having a $3.00 one, and then there is MEM with none. In addition to the PFC and the TSA fees mentioned above there is a US Segment tax of $3.80 per segment. So the total for adding a segment to a non-stop routing is generally 4.50 + 2.50 + 3.80 = $10.80
The PFC and TSA fees max out at 2 segments in each direction. So if you already have connection on your itin, adding another segment won't add these fees. It's the non-stop to one-stop changes that take the big hit.