Please feel free to add to or correct the information herein.
NOTE: For involuntary award changes (caused by the operating carriers), see Involuntary Award Changes / What To Do (merged threads).

Ordinarily, one must call to request or make changes to award tickets.

Award changes, ordinary

NOTE: More extensive listing of terms and conditions are listed in oneworld and other all partner awards rules, Information 2015 on

Award carrier, connection, date or routing changes: As long as origin and destination (but read on for exceptions such as first / last segment) remain the same, change / award redeposit fees are usually waived for awards under certain circumstances when date, connection, routing or carrier changes are made But:Airline / carrier changes incur no change or redeposit fees as long as you do not try to change between all AA oneworld airlines and non-oneworld airlines or vice versa.

E.g. an AA award such as SEA-HNL-SYD using AS can not be changed to use JL without requiring award redeposit. An award using AA LAX-HKG can be changed to JL via NRT or CX Without redeposit ing miles.

If Maximum Permitted Miles (usually 125% of the most direct available routing) for an award is exceeded, two awards may be charged

or

MSC fare requirements: The most significant or prevailing carrier, usually the one with the transoceanic sector, must offer an unconstructed fare between desired origin and destination; if a fare would require "married segments", two awards may be required.
Award validity: Awards must be used within one year of original booking. For travel beyond that, the award miles will have to be redeposited and new awards secured.

Award cancellations can be by phone or online, but online cancellation requires separate action to reinstate the miles. Canceling online does not request or result in miles redeposit.

Award miles reinstatement: Redeposit fees are waived for Executive Platinum members. See here for more information on award miles reinstatement.

"Upgrading" class of service by using miles requires redepositing the original award and issuing a new one for the higher class if service. AA will waive the deposit fee on the redeposited award, and will not charge for this. (However, taxes may differ, such as going from the discounted U.K. Air Passenger Duty to the full APD if upgrading from Y / PE to J; if there are higher taxes and fees imposed by the new fare, the passenger is charged for those.)

Co-terminals: For award purposes, there are no co-terminals; changing co-terminal airports (MIA and FLL, PBI; JFK, LGA, EWR etc.) will incur a $150 change fee. See this thread for detail on award miles redeposit.

An award using AS, FJ, HA or TN to South Pacific (e.g. AKL, SYD) can not be changed to AA or QF without requiring award redeposit (or vice versa).

Dropping segments: Awards made on AA or / and "all partner" carriers will allow changes mentioned above without requiring redeposit fees. Instances of dropping an origin segment can be allowed, or a final segment - as long as doing so does not change the destination zone (or sub-zone, in the case of intra-North America awards); changing the mileage (miles required) of the award claimed or the number of awards claimed.

Segments can be dropped as long as doing so does not change the destination zone (or sub-zone, in the case of intra-North America awards). If you are refused, refer agents to the in-house memo/advisory dated 02/03/11 entitled "Dropping OWFA segments." (guv1976)

As JonNYC posted:

This document was current as of December 2014:
For permitted changes and fees, see this post in the airline partner award thread.

If the award is AA and oneworld, changes may be made as long as the main / governing /Most Significant Carrier makes an unconstructed fare on the award routing and the governing fare's carrier is not changed to one not offering such a fare.

Close-in booking fee: Changes made to bring travel to under 21 days from award issue will incur close-in booking fees of $75.

Schedule changes: On international awards, schedule changes of two hours or longer, or those breaking connections by bringing them below MCT / minimum connection times, flight cancellations, generally may be cancelled and redeposited without fees, or engender greater flexibility in changes. With AA awards, it is possible award seating may be opened when there is none; with partners, AA can appeal to the Liaison to the partner to open seating in these cases (the partner airline may or may not grant the exception requested). Equipment change constitutes a schedule change and you will be able to get the fee waived pre this thread: http://www.flyertalk.com/forum/ameri...solidated.html

Partner changes: If the award includes non-oneworld partners such as AS, EY, FJ or TN, or a oneworld carrier award is changed to include a non-oneworld carrier, or vice versa, significant fees will be incurred ($150).

"Upgrading" class of service by using miles requires redepositing the original award and issuing a new one for the higher class if service. AA will waive the deposit fee on the redeposited award, and will not charge for this. (However, taxes may differ, such as going from the discounted U.K. Air Passenger Duty to the full APD if upgrading from Y / PE to J; if there are higher taxes abd fees imposed by the new fare, the passenger is charged for those.)

Changes that require different award type -

Changes to the itinerary which involve different AAdvantage award(s) than originally ticketed require a reinstatement of the original award ticket, payment of the applicable award reinstatement charge (see below), and a new award ticket issued (waived for AAdvantage Executive Platinum members using miles from their account). However, SAAver awards canceled for AAnytime awards, or changing to a higher class of service, will not incur redeposit fees.

Changes to your outbound travel date, resulting in a departure within 21 days -

Close-in booking fee: A $75 USD award processing charge will apply for a confirmed change to the date on an AAdvantage MileSAAver and AAnytime award ticket if the change results in a new outbound travel date that is within 21 days of the original booking date (waived for AAdvantage elite members using miles from their account).

Contact AAdvantage Reservations to change your itinerary, pay the applicable charge and have your ticket reissued prior to travel.

Canceling Awards / Reinstating Award Tickets
(Waived for AAdvantage Executive Platinum members using miles from their account)

AAdvantage® mileage will be reinstated for unused and unexpired awards upon payment of a processing fee. For tickets booked on or after November 1, 2018, AAdvantage®mileage will be reinstated upon payment of a processing fee for unused and unexpired awards canceled prior to departure. For each additional award reinstatement from the same account at the same time, an additional charge will be collected. These charges are payable by credit card.

Award class changes: MileSAAver to AAnytime changes generally incur no fees; conversely, AAnytime to MileSAAver awards generally will.

Award cabin class "upgrades" (e.g. Y to J): If the change made is an increase of miles to another cabin class, fees are not normally charged (but some government required fees such as UK Air Passenger Duty, airport passenger facility fees, etc. may change).

Redepositing awards incurs a fee of $150 other than for Executive Platinum members redepositing to their accounts. If two or more awards are being redeposited to the same account at the same time, the fees are $150 for the first award, $25 for every award thereafter. Note the awards do not have to share the same PNR, though some less knowledgeable agents will insist so.

Note: given a 120 hr / 5 day hold is offered, there is no right to “Free” cancellation (without redeposit) within 24 hours of securing the award. OTOH, mere date changes to a year from Booking are free of charge in most instances.

Please see: State of the award reinstatement fee (Nov 2015 - clarifying)
FAQ: Cancel award ticket / cancellation (time frame, taxes, etc.) (merged threads)
Link to ARCHIVE 2017: Award Change for date, time, routing, co-terminal, cost, all changes.
Link to ARCHIVE 2015-2016: Award Change for date, time, routing, co-terminal, cost, all changes.
Link to ARCHIVE 2012-14: Award Change for date, time, routing, co-terminal, cost, all changes.