N.B. Different than "standby"; see link.

NOTE CHANGED POLICY: June 2018 - E class availability is not (or no longer) definitive on whether SDFC may happen. "Other" aspects may be taken in to consideration. Seems few other changes but it is now clear that passengers in domestic premium cabins can SDFC at no charge. More here: Guide: New SDFC / Same Day Flight Change Restrictions 8 Jun 2018


NOTE CHANGED POLICY: As of 15 January 2016 the SDFC option will be limited to alternate flights only if they follow the same origin, destination, and also SAME CONNECTION POINT. Other rules seem to be unchanged as far as available 24-hours before, no charge to CK, EXP or up to three companions on the same PNR, no co-terminals allowed, and slight overlap to calendar date limitation for late night may be possible. Domestic segments that are part of a domestic and international itinerary are generally not eligible.

NOTE 1 re upgrades: To effectively use SDFC you must call to downgrade first. If you SDFC successfully then, you may request an upgrade on your new flight.

NOTE 2 re Upgrades. On SDFC, for e500 or EXP UDU the original upgrade request time stamp remains on the upgrade request; with SWU, you will get a new time of request time stamp. (It's useful not to check in for ~10 minutes after you SDFC or you may find yourself in a pickle with upgrade requests.)

NOTE 3 re PreCheck / KTN: For an unknown reason, going on to SDFC May delete or eliminate your Known Traveler number for the record, so your PreCheck will likely not be granted. You'll have to call or have the ticket counter restore your KTN. (According to reports in May 2018, this does not seem to be a pervasive issue any longer).

N.B. This thread relates to AA "domestic" changes only, for international same day changes see this thread.


Link to American Airlines' current policy on Same Day Flight Change and detailed Terms and Conditions

Link AA FAQ - Same Day Flight Change

Link to archived posts made before the recent changes

The price to confirm same day flight change is now $75* (free for EXPs and others as shown in "Complimentary..." below as of 1 Jan 2015):
http://www.aa.com/aa/pubcontent/en_U...eDayTravel.jsp Same-Day Flight Changes

Did you know you can change your domestic flight† and get a confirmed seat for a $75 (non-refundable) charge? The option is available on all fares in the Main Cabin. For $75 you can confirm a seat on a different flight as long as the alternate flight:

1. Has the same origin AND destination
2. Is the same calendar day of departure
3. Has eligible seats available ("E" fare inventory for all fares)

We continue to offer the same-day stand by option for an earlier or later domestic flight for select customers at no charge. See above link for list of select customers.

We now have four convenient options to make same-day flight changes:

1. Online: Beginning 24 hours prior to departure, you can request a same-day flight change on aa.com through the check-in window. Just select each passenger who is requesting a flight change and pay the non-refundable $75 per passenger charge.

2. Over the Phone: Beginning 24 hours prior to departure, you can call Reservations and our agents will provide information for available flights departing on the same day as your original flight. The non-refundable $75 charge can be paid over the phone via credit card.

Once you arrive at the airport, you can check in for your new flight at Curbside Check-In, Self-Service Check-In, or our ticket counter.

3. At a Check-In Kiosk: Beginning 12 hours prior to departure, the Self-Service Check-In machines will provide a list of available flights for the same day as your original flight. Just choose the flight, pay the non-refundable $75 charge, and complete the check-in process. You will receive a boarding pass for your newly confirmed flight and a receipt for the charge.

4. At the Ticket Counter: Beginning 24 hours prior to departure, our agents can provide a list of available flights for the same day as your original flight. Just choose the flight and pay the non-refundable $75 charge. You will receive a boarding pass for your newly confirmed flight and a receipt for the charge.

Same-day flight changes are subject to Terms and Conditions.

†Available for flights in the U.S., Puerto Rico, U.S. Virgin Islands, Canada and the Caribbean on American Airlines, American Eagle® and AmericanConnection®.

*Note: 1.Passengers traveling on unrestricted Y fares and AAdvantage AAnytime travel awards have the flexibility to change flight arrangements at no charge. Passengers traveling on AAdvantage MileSAAver awards continue to have the flexibility to change the date/time of their flights at no charge, provided award seats are available on the desired flight. If award seats are not available on the desired flight, you may obtain a confirmed seat on the same day by paying the $75 charge.



Complimentary confirmed flight change (Link)

Get a complimentary same-day confirmed flight change with:

Tips

Passengers traveling on unrestricted Y fares and AAdvantage AAnytime travel awards have the flexibility to change flight arrangements at no charge. Passengers traveling on AAdvantage MileSAAver awards continue to have the flexibility to change the date/time of their flights at no charge, provided award seats are available on the desired flight. If award seats are not available on the desired flight, you may obtain a confirmed seat on the same day by paying the $75 charge.

Customers who purchased a Choice Plus fare have the flexibility to change one flight at no charge, provided seats are available on the desired flight.
Looking for more information? Please see our Frequently Asked Questions.

†Available for flights in the U.S., Puerto Rico, U.S. Virgin Islands, Canada and the Caribbean on American Airlines, American Eagle and American Connection®.

* Same-day flight change charges are non-refundable. Same-day standby charges are automatically refunded if you are not accommodated on the standby flight.

. . . N.B. Inventory must be available in "E" bucket for Confirmed Flight Change to be offered; even then it still may not be available due to "Other" considerations.

Link to AA Same Day Confirmed Flight a Change Terms and Conditions

Link to aa.com Same Day Flight Change policy

Link to aa.com Same Day Travel Changes / SDFC and Standby FAQ

Archive of previous terms and conditions: http://web.archive.org/web/201405221...mers/sd-tc.jsp


Nuances and Loose Rules

Now for the hard part: figuring out where the flexibility is in the rules. This list is compiled from the responses to people saying "Can I do X?" where X is something that is not clearly permitted by the rules. One's likelihood of success here depends a bit on the method used for the SDC. (Note: this is a work in progress and your contributions/corrections are appreciated!)

For each item, the following codes apply:
Y = possible using any method
A = possible using an agent (phone/counter), perhaps having to HUACA
A* = mixed reports of success with an agent (phone/counter)
N* = possible only if you find a very accommodating agent
N = little or no reported success.
Link to archive thread of older posts.

ARCHIVE of AA FAQ and previous detail of SDFC:
Wayback Machine, 5 captures, 22 Jan 14 - 10 Apr 15
Link

Same-Day Flight Change Terms and Conditions

• Same-Day Flight Change is only available on flights operated and marketed by American Airlines, or marketed by American Airlines and operated by American Eagle or American Connection® carriers
  
• Same-Day Flight Change will be offered to eligible passengers beginning 24 hours prior to departure through the check-in window. Eligibility shall be determined based on, but not limited to, the following factors: AAdvantage or oneworld® elite status membership, purchased fare class, ticketing status and purchase history
  
• Same-Day Flight Change is subject to availability of eligible inventory
  
• Same-Day Flight Change is non-transferable
  
• Passengers who purchase Same-Day Flight Change and are unable to use it due to an involuntary routing change, flight cancellation, or missed connection due to a late incoming flight are eligible for a refund. The refund will be automatically initiated by American Airlines on the passenger's behalf.
  
• Passengers who are late for a flight for reasons other than those listed above are not eligible for a refund of the Same-Day Flight Change
  
• Passengers that have purchased a Same-Day Flight Change will not receive a refund if the price decreases, nor incur a charge if the price increases
  
• Any refund request will be fully refunded, or denied. There will be no partial refunds of a Same-Day Flight Change.
  
• Refunds of Same-Day Flight Change will be made to the original form of payment
  
• Purchases made in cash will be refunded via check
  
• Refund requests must be received within 365 days of the original Same-Day Flight Change purchase
  
• Same-Day Flight Change reservations are subject to cancellation unless passengers have checked in and obtained a boarding pass within the check-in window. Passengers must be present at the departure gate and ready to board at least 15 minutes prior to scheduled departure time to retain their reservations.
  
• American Airlines expressly reserves the right in its absolute discretion to discontinue Same-Day Flight Change at any time. American Airlines will not be liable for any loss or damage suffered by a purchaser resulting from such refusal, cancellation or denial
  
• American Airlines reserves the right to remove any passenger for inappropriate behavior, including, but not limited to, conduct that is disruptive, abusive or violent. Such passengers will not be entitled to a refund.
  
• American Airlines reserves the right to move any passenger from any seat for operational or security reasons. This includes passengers who do not meet exit row eligibility requirements. If a passenger is involuntarily moved to a different flight for such reasons, the passenger may request a refund of the Same-Day Flight Change at aa.com/refunds

Same-Day Standby Terms and Conditions

• Same-Day Standby is only available on flights operated and marketed by American Airlines, or marketed by American Airlines and operated by American Eagle or American Connection® carriers
  
• AAdvantage regular members and non-members may only use Same-Day Standby if Same-Day Flight Change is not available
  
• Same-Day Standby will be offered to eligible passengers beginning 24 hours prior to departure through the check-in window. Eligibility shall be determined based on, but not limited to, the following factors: AAdvantage or oneworld® elite status membership, purchased fare class, ticketing status, origin and destination, and purchase history
  
• AAdvantage regular members and non-members using Same-Day Standby may only stand by for an earlier flight with the same routing on the day of travel
  
• Same-Day Standby is subject to availability of eligible inventory
  
• Same-Day Standby is non-transferable
  
• Passengers who purchase Same-Day Standby and are unable to use it due to lack of available inventory, cancellation of standby flight, or involuntary routing change are eligible for a refund. The refund will be automatically initiated by American Airlines on the passenger's behalf once the passenger completes travel on their ticketed itinerary.
  
• Passengers that have purchased a Same-Day Standby will not receive a refund if the price decreases, nor incur a charge if the price increases
  
• Any refund request will be fully refunded, or denied. There will be no partial refunds of a Same-Day Standby.
  
• Refunds of Same-Day Standby will be made to the original form of payment
  
• Purchases made in cash will be refunded via check
  
• Refund requests must be received within 365 days of the original Same-Day Standby purchase
  
• Same-Day Standby requests are subject to cancellation unless passengers have checked in and obtained a boarding pass within the check-in window. Passengers must be present at the departure gate and ready to board at least 15 minutes prior to scheduled departure time to retain their reservations.
  
• American Airlines expressly reserves the right in its absolute discretion to discontinue Same-Day Standby at any time. American Airlines will not be liable for any loss or damage suffered by a purchaser resulting from such refusal, cancellation or denial
  
• American Airlines reserves the right to remove any passenger for inappropriate behavior, including, but not limited to, conduct that is disruptive, abusive or violent. Such passengers will not be entitled to a refund.
  
• American Airlines reserves the right to move any passenger from any seat for operational or security reasons. This includes passengers who do not meet exit row eligibility requirements. If a passenger is involuntarily moved to a different flight for such reasons, the passenger may request a refund of the Same-Day Standby at aa.com/refunds