This topic comes up a lot, so I thought I'd post something I just wrote for the United forum.

I hope this helps you get those savings you are entitled to.

Type A and Type B are standard industry terms for marketing or customer service forms. Type A is a discount certificate, which reduces a fare. Type B is a voucher, which has value and is exchanged for a ticket.

On United, in my experience, CS25 and CS50 PMO/Dollar PMO/Friends are all Type A - Discount Certificate. The Denied Boarding Compensation vouchers I have seen are Type B - Voucher. Other customer service dollar certificates could be either type. The certificate or its detailed rule should tell which.

If you want to see the procedures for ticketing, check

http://www.arccorp.com/forms/pp/iah6_0_2.pdf

http://www.arccorp.com/forms/iar/iarbook.pdf

Regrettably, I have yet to find a definitive source that makes it clear that one can apply a Type A and a Type B to the same ticket, although the logic seems clear. The Type A form reduces the fare you are paying and then the Type B form is exchanged as full or partial payment for the reduced fare.

If anyone can get a reference from a carrier or the ARC that spells this out, it would be very useful.

It's possible for a single form to be treated as either a Type A or a Type B if the airline wants it that way as these references explain.

Charles