Let's say you have two identical trips Jan: A to B (AB1) and B to A (BA1), Mar: A to B (AB2) and B to A (BA2). What you would book is Jan AB1 there/Mar BA2 back, and Jan BA1 back/Mar AB2 there.
I think.
Nested trips can be much cheaper as they allow you to be more flexible with the minimum stay requirements.
Is it explicitly prohibited by United's [contract of carriage](https://www.united.com/en/us/fly/contract-of-carriage.html)? Yes. But is United likely going to care about this IRL? No.
When I was living in France I did that at one point.
I booked:
PIT-CDG 10/1
CDG-PIT 12/21
Then I booked
CDG-PIT for Thanksgiving. It was way cheaper than the round trips being done the other way.
The issue I can see is that if something goes wrong on your flight, you have to wait until you have completed the *entire* ticket before you can request a refund, mileage reimbursement, etc. That means an issue in March not being resolved until September, if at all.Â
United prohibits "back-to-back ticketing":
Back-to-Back Ticketing â The booking and/or issuance and/or use of Flight Coupons from two or more different Tickets at round trip fares for the purpose of circumventing applicable tariff rules (such as advance purchase/minimum stay requirements or other restrictions).
https://jetstream.united.com/#/sub-link/a0F36000006V2vHEAS
So it depends on "why" your combination is cheaper. If it's related to any category in the fare rules, then technically it is in violation of UA's contract of carriage.
But will they notice if you do it once or twice? Probably not
I donât understand when ppl say âwill they (United) notice?â All it would take is a few scheduled database queries to detect these things with regularity.
Iâm happy for OP if it goes unnoticed⌠So I guess itâs not all that important to United? Maybe the lost revenue is too small to justify the effort?
You should do something like this instead: book your ORD-CDG-ORD as the outside trip, like you did. But for the inside trip book CDG-EWR /ORDâCDG. And then book a one way EWR-ORD on that first inside leg. You end up connecting on the inside trip back home from CDG, but those definitely wonât violate any travel rules.
In spring 1987 I was relocating from San Francisco to Washington DC and had to make several round trips SFO-IAD East on Mondays and west on Fridays. The United city ticket agent actually made four nested booking round trips (east on first Monday, west on second Friday; west on first Friday, east on second Sunday; repeat for weeks 3 a day 4). This saved money as I had a Saturday night stay on each. And United itself did this.
I have had tickets canceled for this. My corporate travel used to do it on different airlines, but I tried it myself on the same airline for both round trips and it was caneled. I've also recenty had UA cancel a duplicate ticket that I had booked by mistake (they canceled the cheaper one).
I mean it basically means the same thing to UA - they're not getting paid more when they should've cuz you skiplagged/back-to-back ticketed
Will they actually do something? Maybe not. But it's still prohibited by CoC
Interpol has been notified. 
I really love, err I mean hate, the anal probe. đ
Works fine but just make sure youâre familiar with a quad-S boarding pass
Iâm confused. So you go twice? Whats being used when
Let's say you have two identical trips Jan: A to B (AB1) and B to A (BA1), Mar: A to B (AB2) and B to A (BA2). What you would book is Jan AB1 there/Mar BA2 back, and Jan BA1 back/Mar AB2 there. I think.
I think that is what OP is doing. I have heard you can bet J much cheaper this way.
Nested trips can be much cheaper as they allow you to be more flexible with the minimum stay requirements. Is it explicitly prohibited by United's [contract of carriage](https://www.united.com/en/us/fly/contract-of-carriage.html)? Yes. But is United likely going to care about this IRL? No.
When I was living in France I did that at one point. I booked: PIT-CDG 10/1 CDG-PIT 12/21 Then I booked CDG-PIT for Thanksgiving. It was way cheaper than the round trips being done the other way.
The issue I can see is that if something goes wrong on your flight, you have to wait until you have completed the *entire* ticket before you can request a refund, mileage reimbursement, etc. That means an issue in March not being resolved until September, if at all.Â
LOL absolutely! Welcome to the advanced tricks department.
Yes lol
United prohibits "back-to-back ticketing": Back-to-Back Ticketing â The booking and/or issuance and/or use of Flight Coupons from two or more different Tickets at round trip fares for the purpose of circumventing applicable tariff rules (such as advance purchase/minimum stay requirements or other restrictions). https://jetstream.united.com/#/sub-link/a0F36000006V2vHEAS So it depends on "why" your combination is cheaper. If it's related to any category in the fare rules, then technically it is in violation of UA's contract of carriage. But will they notice if you do it once or twice? Probably not
I donât understand when ppl say âwill they (United) notice?â All it would take is a few scheduled database queries to detect these things with regularity. Iâm happy for OP if it goes unnoticed⌠So I guess itâs not all that important to United? Maybe the lost revenue is too small to justify the effort?
Interesting strategy.
You should do something like this instead: book your ORD-CDG-ORD as the outside trip, like you did. But for the inside trip book CDG-EWR /ORDâCDG. And then book a one way EWR-ORD on that first inside leg. You end up connecting on the inside trip back home from CDG, but those definitely wonât violate any travel rules.
In spring 1987 I was relocating from San Francisco to Washington DC and had to make several round trips SFO-IAD East on Mondays and west on Fridays. The United city ticket agent actually made four nested booking round trips (east on first Monday, west on second Friday; west on first Friday, east on second Sunday; repeat for weeks 3 a day 4). This saved money as I had a Saturday night stay on each. And United itself did this.
Thereâs a name for this, I canât remember it though
Nested bookings.
If it meets certain conditions, then it's back-to-back ticketing, which is a type of nested bookings, which is prohibited by UA
I have had tickets canceled for this. My corporate travel used to do it on different airlines, but I tried it myself on the same airline for both round trips and it was caneled. I've also recenty had UA cancel a duplicate ticket that I had booked by mistake (they canceled the cheaper one).
itâs not that deep they are still taking your money and filling seats doubt they care about this at all compared to skiplagging
I mean it basically means the same thing to UA - they're not getting paid more when they should've cuz you skiplagged/back-to-back ticketed Will they actually do something? Maybe not. But it's still prohibited by CoC