Be careful Rudi, you're wandering into the realm of 'back-to-back' ticketing... perhaps your 'friend' does this?

What I don't understand is when a one-way ticket costs more than a return... who, going one-way, would be willing to pay more money for half the miles?? I'm inclined to fly the first half of the ticket, & throw away the return portion. Is there some rule against this?

There are rules against everything that we do on a regular basis. You can get around some of this, e.g. back to back ticketing using two unrelated airlines etc.. See the website www.rulesoftheair.com for explanation of some of the most common rules for US Airlines. Canada's airlines don't seem to be (so far) as anal about this. After all, would they rather have someone back to back ticketing on one (their airline) or only getting one of the fares so you can stay legal? A sample of AA's throwaway rule from that site:

American Airlines - Tickets: Throwaway
Domestic General Rules Tariff DGR-1
--------------------------------------------------------------------------------

You need a one way ticket from Chicago to Seattle …

American Airlines’ lowest one way fare is $891.
American Airlines’ lowest round trip fare is $518.
Why not buy a round trip ticket and travel only one way?

Seems logical, right?

American Airlines surely doesn’t have a rule against this do they? Yes they do.

Purchasing a round trip excursion fare ticket and traveling only one way is called "throwaway" ticketing and American Airlines prohibits "throwaway" ticketing.

If American Airlines determines that you have purchased a "throwaway" ticket, they can:

Cancel any remaining portion of your itinerary,
Confiscate any of your unused flight coupons,
Refuse to board you or check your baggage, or
Charge you the difference between the fare you paid for the round trip ticket and the fare you would have paid for a one way ticket.
How will they know? After all, by the time American Airlines realizes that you did not use the return portion of your ticket you are already at your destination. Are they going to hunt you down and forcibly put you on a return flight? Of course not. What they can do, however, is go after your travel agent.

The business agreement between your travel agent and American Airlines requires your travel agent to abide by all American Airlines ticketing rules. Writing "throwaway" tickets is a violation of such rules and if American Airlines determines that your travel agent is continually engaging in such ticketing practices, they can debit the travel agent for the fare difference - the difference between the round trip fare you paid and the one way fare you should have paid.

You can also see a news story (1997) on back to back ticketing on CNN at http://cnn.com/TRAVEL/NEWS/9709/29/backtoback.ticketing/

OH DEAR--looks like we have wandered way off topic. I guess we should start a new thread if people want to continue this.

yes baobab (thank you) - for "sure", with I would I meant "my friend explains to me he would".

And he (my friend) adds:

unfortunately I later found out, that I could not use the return ticket due to circumstances out of my control, and heeven had to change his return-airport (for example instead of back to San Francisco he had to fly back to Oakland or San Jose, instead of LGA it was JFW, instead of Denver it was Colorado Springs).

(Regarding Denver/Colorado Springs: last year, my supplementary end-of-year-flight to pass the 100K-limit was SFO - Denver - Colorado Springs and than back the same day. SFO-DEN would have given me enough miles - but the supplementary leg to/from COS made the UA ticket 150$ cheaper ... this spared money was then better invested in a long lunch/drinks at the Broadmoor).

BlondeBomber: in fact I practically never use a travel-agent.

And I haven't really used this "back-to-back"-policy myself in the USA, as normally I do the high-priced segments in the US with "visit-the-USA-coupons" which cost me in average 60$ per flight-number on UA (limits are: out of 8 flights only 2 are allowed coast-to-coast, stopovers = more than 24 hours only twice at the same airport, and I can use them for 60 days after the first segment, and have to start using them 30 days after my transatlantic arrival). Those tickets are eligible for upgrade (as Premier).

I feel sooooooooo discriminated against. Rudi: guess those make up for all the other things you don't get from here.

Well, I am one of those "lawyers bill their clients," but that means I must frequently take trips without a Saturday overnight, and frequently change plans when things get cancelled for one reason or another, often only a couple of hours before the flight. Thus, I am frequently relegated to the "Y" fare. I would certainly use other fares if necessary.
In fact, I just returned today from a quick overnight to Atlanta to take two depositions, so of course I booked on Delta, given the future $99 companion ticket offer that they were running if purchased by December 6. Flew down Monday morning and back on Tuesday.
Tried to get upgraded, but couldn't.

djlawman - I think that the world is divided into two types of ffs - those whose employers insist that they stay a Saturday night in order to minimize costs, and those whose employers insist that they drop everything and rearrange their plans at the last minute in order to get something done. The former know their itinerary well in advance and fly on cheap restricted tickets, the latter have little control over their own lives, but fly on full fare tickets.

Time is money - it just depends on the 'exchange rate'.

Gee, Baobab, you sure know how to make a guy feel worthless ;o)

I must be dumb... I still don't understand this back to back ticketing thing (or it could be I'm tired from 10.5 hours of work!)

Still I rather fly the round trip and if I have to change... and forced to pay a small fee then swallow and move on. CATMAN

Catman:

I'll give it a shot as to what my understanding of it is. Y'all correct me if I'm wrong, OK?

Say you've got to make 2 round trips from Atlanta to Philly; Leave one Monday (day 1), return Friday (day 5), then leave again the next Monday (day 8), then return Friday again (day 12).

If you buy your first ticket to leave on day 1, then return on day 12, that ticket spans a Saturday and is eligible for a lower fare. If you buy your SECOND ticket as a round trip FROM Philly TO ATL on day 5, returning TO Philly on day 8, you have spanned the SAME Saturday with both tickets, getting the lower rate both times.

The airlines, they no like this.

I get around it by initially buying a one way ATL to PHL, then round trips PHL-ATL, spanning the weekend. On my last trip, I get a one way PHL-ATL. Or, get the first ticket as a round trip on one airline, then the others on a second, or...etc.

This was how our corporate travel agent explained it to me. I hope I'm right and wasn't too confusing in my explanation.

-Harry

Thanks Harry. You cleared up my confusion
mostly, but I don't think I want to try to scam the airlines. I would be one to be banned from all Frequent Flyer and guest program and would have to put propellers on the cats to get anywhere! CATMAN

see my previous post and read about all these things under http://www.rulesoftheair.com/

I don't think it is "scamming" or illegal when you do back to back ticketing on two unrelated airlines. It only violates the internal rules of an airline if you do both tickets on the same airline. As someone said, antitrust legislation could come in if two airlines conspired against you. What I don't understand is why the airlines don't simplify their fares so that a discount fare is half a full fare (this might mean lowering full fares and raising discount and sticking to a 14 day advance purchase rule). That would discourage back to back ticketing as there would be no real financial advantage to doing it. The airlines actually allow back to back ticketing through their own on-line sales---they don't seem to police it all that well. I can't understand why they would go after travel agents who they have knocked the commissions down on anyway.
Last point: I don't think this is a huge problem that has hurt them horribly--just look at the record profits some of them are making!

or "my friend" takes the second ticket with the same airline, but on another ff-account (f.e. for UA flights: 1st ticket on his UA-mileage plus, 2nd LH-miles&more).