Is it me? Is it Delta?

It's both of you. :)

You're not trying to fly open jaw. Open jaw would be AMS-SEA, then return PDX-AMS. That's open jaw.

What you're actually trying to do is a "multi-city" flight: A to B, then B to C, then C to A.

On the Delta website, try clicking the "Multi-city" tab. You will be booking 3 flights.

Prepare for some sticker shock. And beware "basic economy" flights.

I'd probably try doing an open jaw on Delta: fly AMS-SEA and then DTW-AMS on one ticket - see how that prices out.

And do one-way flights between Seattle, South Bend, and Detroit.

I'd probably try doing an open jaw on Delta: fly AMS-SEA and then DTW-AMS on one ticket...

Yeah, a good chance that would be less expensive, so worth checking.

Still, for an open jaw flight (as suggested there), use the Multi-city tab.

I just did a dummy booking for random dates in July using the Multi-City tab that you find right on the Delta homepage.
I spaced them out like you described in your posting and had no difficulties finding flights. FYI total fare. AMS-SEA-South Bend-AMS (via DTW) was $1668

Picked random dates in June ( "multi city')

Found AMS-SEA ( via YVR) //then SEA-SBN 3 days later and then SBN-AMS 5 days later at 1550 euro for the entire trip

EDIT-- Was able to get all those flights to show up as a single booking/ticket

I just got off the phone with Delta. There was no hold time. You might call them and ask for assistance booking the flight. Tell them it is complicated and they MAY help you by booking it themselves. Make it clear you do not care to pay a reservation fee. I usually have decent luck over the phone with Delta and they have been even more helpful of late.

Or call. If you can't get the website to work, they should waive the fee for the booking--but verify first.

the advice to book the Seattle South/Bend/DTW on another airline will not save you any money on this particular arrangement. Keep your life, and your ticket, as straight forward as possible by sticking with Delta.

Carol, my suggestion was based on an assumption that the legs to South Bend were the problem. I did not see that others had already found the route on Delta as requested. And just now I found the same thing, good flights for €1569. I will note that initially only the Delta One flight showed up, for something like €11,000. But I waited for more to load, and the regular Economy flights showed up.

I often use ITA Matrix to check on flights. Google Flights is faster, however.

United Airlines flies to SEATAC from Amsterdam and she could fly to South Bend thru Chicago ODD on a connecting flight. South Bend is just 95 miles from.Chicago where Detroit is 220 miles from South Bend.

If I were doing a 5 day layover in South Bend, I'd look at booking the ticket as multi-city with AMS-SEA then DTW-AMS with a separate flight for SEA-SBN.

But I do understand what you are saying. If you've tried the multi-city approach and still have the same results, I'd take a screen shot of what I'm seeing for both the frustrating screen and then the straight RT to SEA with its prices. Then call Delta and explain what you're trying to do.

Do either you or your daughter have any frequent flyer status with Delta? If not, go ahead and sign up for your daughter who is doing the flying. Miles gained on this trip will go toward future flyer status, and sometimes that helps if there is a last minute issue at the gate.

Aquamarinesteph, joe and I and others were able to a dummy booking on Delta with the exact itinerary requested by the OP, with a 3-day stopover in Seattle and 5 days in South Bend. All on one ticket using the multi-city function on the website. I saw the total as around €1550 ( priced in euros due to the flight origination in Europe). So no need to break it into separate segments.

Lola -

I know it's doable, but I must have missed the dates we're looking at here. I just know from my own experiences that sometimes smaller airports (like South Bend) often raise the overall ticket price based on factors beyond anyone's control.

Thanks to all for your input. And the explanation of open-jaw vrs multi city flights.
At least I know it's not just me. It used to be that you could select your flights, select your seats, and upgrade each seat individually if you chose to do so. Easy-peasy.

PS. I did use the multi city tab.

I would do as Andrew H. advised. That's what I usually do when I travel home to the States. Buy my Europe/US entry and departure tix, and then go to Southwest (or Alaska or whoever serves your area) for the internal flights. It's worth at least looking at.

What dates is she looking to fly? I do not understand the trouble younare having, as two of us have found the multi-city trip specified right on the Delta website, putting in the date and destination separately for each leg of the trip (3 legs in all). It is all on one ticket for €1550 or less (I just saw €1467).

If you cannot find the same, it may be the dates (too close?) or perhaps your browser. I am using Safari on an iPad. Don't know what Joe up in Edmonds uses.

It's either the dates or user error. :)

Yesterday I also tried doing it all on Delta as a multi-city ticket. AMS-SEA, SEA-SBN, SBN-AMS.
I too was getting an all-in price of around 1500 Euro, plugging in random dates in September. That's probably a normal price for this routing, and doesn't sound too terribly out of line with what I'd expect.

I don't think Detroit is in the mix, leave that out, it just complicates things. Let Delta's booking engine worry about where the connecting airports are.

Back in the day, before airlines like Delta worked hard to find new ways to shake down customers for every penny they could possibly squeeze from you, it used to be possible to select where your stops on an itinerary were, play creative games with "stopovers" and such. Much of that flexibility is now gone. They've gamed the system so it spits out what it thinks is the right option for you, and you typically can't change the routing, or choosing a routing you prefer will cost you more (maybe lots more!). So if they want to route your Seattle to South Bend flight with connections in Phoenix and Atlanta, that's what they're going to do - unless you're willing to buy your way out of that nonsense.

Sometimes it works OK for the consumer (the routing I saw with dummy dates was perfectly reasonable), and sometimes it sucks, requiring you to choose from a miserable routing with multiple long stops or spending double to get a rational routing.

That's what you get when airlines gobble each other up to reduce competition, and 99% of the traveling public only shop for flights with a single criteria (the absolute cheapest price).