A segment is one flight including any stopovers 4 hours or less is a segment. SFO-DFW-CDG is Segment 1
CDG-LAX-SFO is Segment 2

So you must be at your last destination as your final stop.

You could do 8 segments on one itinerary just linking them together to form a round trip . A stopover is anything over 4 hours unless the airlines forces you to take a 13 hour+ layover. Try looking for flights with an overnight stay so you can sleep at a hotel inbetween arriving at 10:00PM departing at 10:00AM the next morning.

Not for the purpose of elite status, which is the OPs concern. SFO-DFW-CDG would yield two segments toward status on AA, and CDG-LAX-SFO would also earn two (provided one gets segment credit for what must be the Air Tahiti flight).

Again, to reinforce: one-stop flights which have the same through flight number are counted as one segment. For example, flying SEA-JFK-FCO on AA236 will result in one segment's worth of credit and mileage credit commensurate with a SEA-FCO non-stop (despite the change of equipment and gates at JFK). That's two takeoffs, two landings, one segment.

On the other hand, if one were to do a same-day turn on AA215 ORD-MCI-ORD then it would count as two segments. That's because ORD-MCI-ORD is not a through flight number; AA do not operate a one-stop ORD-ORD flight. So that would be two takeoffs, two landings, two segments.

I flew MSY-MIA-TPA. Had a two hour layover in Miami, changed gates/aircraft. The two flights were the same flight number and I ended up getting credit for one segment. This was two years ago, not sure if anything has changed. Since then I pay close attention to flight numbers, as the four times I flew that route I had the same results of 1 segment.

Except when you have more than on takeoff landing with the same flight number

SFO-DFW-CDG would only be one segment if they shared the same flight number. Additionally stops under 24 hours on an international itinerary are not stopovers. I just used an award from LAS-LAX-RDU-LHR-AMM-TLV. I stopped at LAX for 22 hours. That would not have been permitted if a non-stopover connection on an international trip was limited to 4 hours. The international gateway was RDU, so I did a stopover of over 24 hours there.
I didn't really want to go to AMM, but BA had no award seats for LHR-TLV nonstop. And, I really wanted to check out that great RJ club at AMM..........NOT.... I did not spend the $15 for the shower

Is this definition of segment documented anywhere on AA.com or some other official source? I saw in the elite status rules how one-stop flights will earn nonstop mileage (rather than the actual mileage for each leg) but nothing about how that counts as only one segment.

Just to be clear, I'm not disputing the assertion, just wondering what AA says if anything.

I have no idea if it's defined anywhere, but I can assure you that this is how it works in reality.

It is an industry standard.

Definition of Flight Segment



The International Air Transport Association (IATA), the international trade body for airlines around the world, defines a flight segment as the operation of a flight with a single flight designator between the point where passengers first board an aircraft and the passengers' final destination. A flight designator includes an airline code, which has two letters or a number and a letter in combination, and a flight number of up to four digits. A flight segment can include any number of stops where passengers board and deplane the same aircraft operated by a single airline.


Comparison of Flights and Legs



A flight is defined by the IATA as the operation of one or more flight legs with the same flight designator. Unlike a flight segment, a flight may involve one or more aircraft. The IATA defines a leg as the operation of an aircraft from one scheduled departure station to its next scheduled arrival station. A flight segment can include one or more legs operated by a single aircraft with the same flight designator.

Thanks! Good to know that there's a standard definition.

I am booking my year end segment run and planning 4 or 5 trips ORD-MSP-ORD trips and hoping for two segments on each trip. Howveer they operate on same flight number outbound and retrun. Two segments guaranteed?

But unfortunately, it does not. You can have a single flight number with change of gates and change of gauge - DFW-ORD-LHR, same flight number, MD-80 and 772, and it counted as ONE segment when they did not operate a DFW-LHR nonstop (but that's the mileage and segment credit you got regardless).

But if it's outbound and return, it will then count as two segments.

So, AAA-BBB-CCC same flight number, one segment, regardless of IATA or anyone else - AAdvantage is different.

AAA-BBB-AAA same flight number, two segments.

Yes, although you would be well served to watch you flight postings carefully - as the double #'d flights do cause some strange processing issues.

Some of us are sufficiently obsessive-compulsive / mileage-retentive we'd check anyway - or maybe even keep a spreadsheet and check - just because, well, we're FTers.

This was my experience, I got credit for all segments. Thanks for the help.