Are you saying that if I have two tickets: ATL-HND on DL, and a second ticket HND-BKK on JAL that DL is going to insist I meet the requirements for entry into Japan?

Im pretty sure this is incorrect. As long as you have the paperwork to prove you have onward travel that is compliant with the Tiamatic transit rules you are cleared. Being on one ticket isn’t a requirement for any of the places I have experiences with.

Some carriers would require entry paperwork. DL however views it as a transit as long as any checked bags can be checked through.

Can you elaborate how it works in case of misconnect?

Option 1. DL takes responsibility for rebooking. Highly unlikely, because DL has no control of partner ticket.

Option 2. Partner takes responsibility for rebooking per agreement with DL. It’s possible, but then it should also work for situations without checked bags?

Option 3. It’s passenger responsibility to rebook. Possible, but what if rebooking needs to be done on 3rd airline, how bag will be transferred? What if 3rd airline does not have check in / transfer staff in the transit zone (seen plenty of such cases in smaller or non-hub airports) and online check in available? What if there are no reasonably priced rebooking options within transit zone time limit / passenger unable to rebook, will DL get fined for bringing pax without visa and required to take pax back to the origin?

Transit is separate from responsibility to rebook. However with DL as long as both tickets are ST issued, they can take control and reissue other ticket. DL (all ST carriers) have access to a tool that allows them to take control of another ST ticket. (Not all ST carriers despite access are willing to take control, but they can have their ticket taken control of)
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Now if not ST (Other ticket) then you'll generally be on your own to rebook.

DL will treat you as transit as long as have shown 1)have confirmed reservation/ ticket (such that would be a connection if on one ticket, so no over 24hr stops) and 2)any checked bags can be checked through. Might this bite DL, sure. However most countries have no issue with separate tickets (as long as bags are being checked through anyway). It's more the airlines using it as an excuse to sell more expensive tickets. Airline always must bear cost to return passenger, even if they did no wrong. Fines OTOH, it depends on if they verified everything they could. Again, most country rules don't specify must be on one ticket to be "transit."

Everything flyerCO says and:
We keep saying DL, and I accept “some” airlines require you to be able to enter the country on a separate ticket connection. I’ve done this maybe 5-6 times in the past 5 years on multiple airlines and have never had an issues connecting in multiple countries. I don’t check luggage and cannot comment on the interline nuance. As long as I show my onward ticket, I pass the Tiamatic check.

I’ve never experienced a misconnect in these circumstances and can’t comment from personal experience. What I’ve read is that many counties have exceptions to allow people in who experience severe flight disruptions for minimum amount of time.

I can’t promise this is every situation, but the baggage transfers aren’t necessarily human to human. Airports have designated places where transferred luggage goes for each airline and airline 1 drops through luggage off at the designated pickup spot for airline 2.

Some airports with automated luggage systems “know” that the bags go to airline 2 and will put it in the central queue/storage and then release it to the receiving airline… perhaps someone knows the specifics on this.

I still do not understand what happens if:

- There is misconnection
- Customer is unable or unwilling to pay for new flight within “reasonable” timeframe, because it’s too expensive or they do not have money or credit cards not working etc etc.

Will DELTA be responsible for bringing customer back to the point origin?

Will DELTA pay fine, because they brought customer, who does not meet entry requirements?

I don't know... I can imagine other possibilities if someone refuses to pay for the change/buy an onward ticket. One such possibility would be local prosecution for violating immigration law/overstaying a visa. Why do you care about the last question?

Yes DL will have to fly passenger back to point of origin. Airline is required to fly passenger back if passenger is denied entry, regardless of the denial reason. A fine is only levied is airline broke rules.

Example - you've used your maximum 90 days in six months. Airline will have to fly you back, but wouldn't be fined as they have no way of knowing/verifying that.

Any recent experiences with A3? Traveling on DL to ATH and then have a separate A3 flight. I am not counting on having my luggage checked though, but if agents at DCA can do it, it will help us a lot.

"Technically" they are not supposed to do it. Will they, depends upon the check in agent. You won't know for sure until you try. I have even had DL check in agents refuse to check bags (all on DL) over two tickets/PNR's. Have had to ask for a supervisor to make it happen.

I am glad I found this thread. I just asked an agent through chat, as well as a phone agent, if I can check to see if I can connect through to Berlin on a KLM ticket out of AMS. They both said they don't know and that I would need to ask at the airport. I asked if they truly did not know the policy, and both rudely said "no." SMH.

As noted, yes KLM is one of the exception carriers for which DL will, by policy, through check bags across separate tickets. I always recommend bringing a printed copy of the second ticket and a copy of the DL policy page on this in case you get pushback at the airport from an agent who isn’t familiar with the policy. Also, verify the luggage tag shows ALL segments before the agent places the tag on the bag. I say this one from experience, catching it before the bag was tagged and sent off thankfully and the bag was properly retagged before being sent off.
https://pro.delta.com/content/agency/us/en/products-and-services/baggage/delta-s-through-check-baggage-policy-.html

If I have a ticket LAX - SEA on DL in Economy but an onward SEA - CDG separate ticket in Business class with AF -- I know delta will interline luggage all the way through to CDG but what about baggage fees? Will DL charge me baggage fees at LAX even thought SEA - CDG is in business class?

Reporting back: No problem at all out of MSP. The agent out of BER looked at me like I had two heads. I asked to speak to a supervisor, at which point she picked up her cell phone and called someone. I don't speak German but I would put money on it that she called a friend, given the amount of laughing and smiling she was doing.

Does anyone have any experience having bags transferred from DL to Turkish air if on 2 separate tickets. I want to fly DL TPA-JFK, then Turkish business class to IST. Can’t find answer but haven’t called DL.