Not necessarily the case all the time... it depends on your ticket and alliance rules.

I had a SQ-SK overnight connection at LHR which my bags were checked straight through and 'kept' till SK flight the next day. I was on one ticket. Yet on seperate tickets, this was not permitted with similar routing before.

Some years ago, when SQ were flying AMS-ORD, I once had ORD-AMS (SQ) connecting to AMS-ARN-TMP (SK) on a separate ticket, with something like 22 hours in Amsterdam. Nevertheless, at ORD I was able to check my bag all the way through.

(Of course, in practice it didn't actually work. When I got off my last flight at our little Tampere airport, they were waiting for me in the baggage hall with news that my suitcase was in Singapore. Fortunately, I got it a day later.)

cheers,

Henry

AA's rule for thru checking bags on an overnight connection is that the connection must be less than 12 hours. If you have 12 hours or more for a connection, then bags must be reclaimed and then re-checked the next day (4 hours or less prior to departure).

Thanks for the clarificationIIRC there's an exclusion for elites allowing for check-in at any time during the day...but forget (a) what minimum level it applies and (b) whether it applies to all oneworld elites or just AA's own.

I have had lots of baggage checked in for my interline trips with an overnight sub-12 hour connection at LHR where I did not have to claim the bags at LHR. It has ordinarily done me well.

Outside of the US it is pretty normal. I've checked through overnight at SYD, BKK, SIN and ZRH.