Which fare-class does allow stopovers?
 

I am currently looking at an amazing airfare from AMS to ANC (roundtrip for 733 euro), and it is in the K fare class. The routing would be AMS-IAH-ANC-IAH-AMS. (From IAH to ANC and back the plane will make a stop in SEA), and it s bookable on www.unitedairlines.nl

However I have to attend a wedding in Texas so I would like to add a stopover in IAH on the way back to AMS (the actually wedding is in Austin), however the K fare does not allow any stopovers. So which upper fare class would allow stopovers? L? T? S? W?

If I booked a ticket with a stopover in IAH it would cost 881 euro, whole way in K class however the ANC-IAH segments would be in L class
If I booked a ticket with a stopover in AUS it would cost 918euro, allw ay in K class however ANC-AUS is in T class

any of you guys could help me to find the cheapest possible way to fly to ANC and include a stopover in either IAH/AUS, let me know!!

thanks!!

There is no way to know just by the booking code if stopovers are allowed. There are K fares that do allow stopovers (usually for an extra charge) and higher fares that don't. Doing the search the way you've been doing and asking for the lowest fare is the best way to check. It sounds like your date is fixed because of the wedding so what you see is what you get.

The fact that you have a different booking code for ANC-TX and TX-AMS indicates that a stopover fare is not the cheapest option for your travel. Rather, what it's doing is charging you 1/2 RT for each sector travelled (AMS-ANC, ANC-TX, TX-AMS), aka a circle trip. If this is what the computer is doing, it's likely the cheapest way to do it.

You should call the 1K desk and tell them what you want to do. They should be able to find the best booking. The other poster is right that the fare rules vary by city pair and booking code. You're a 1K so I think they waive the phone fee. I wouldn't rely on the website to determine the best fare. Alternatively you could contact a travel agent, they have the same access as a UA agent to the fare information.

Stopover is not determined by fare class, but fare rules.

Use ITA Software for a multi-city fare search and look at the fare construction details. They'll figure out if it's cheaper to do a stopover or circle trip or whatever.

Then see if UA.com produces the same lowest cost option; if not, call to book.