Note that you can't tell whether a fare is refundable or not just from fare class. While AS J class fares are generally refundable, there are C, D, and I fares that are not. You can look in Penalties section under Cancellations to determine whether or not a fare is refundable. Non-refundable fares will say " TICKET IS NON-REFUNDABLE IN CASE OF CANCEL/NO-SHOW." , while refundable fares will say "CANCELLATIONS PERMITTED.". This is pretty much universal among airlines. AS fares will also have an R as last letter of fare basis code for refundable fares and an N for non-refundable fares which is simpler than having go through fare rules.