Originally Posted by
IluvSQ
JL and SQ do have an interline agreement ( I don't know why you would think not).
and there should be no issue checking your bags right through.
The existence of an interline agreement does not obligate a carrier to check through on separate tickets. No personal experience with JL, but I do agree there's a decent chance they will as a courtesy check through on separate tix.
Originally Posted by
IluvSQ
Further, in the unlikely event they do not, when you check in for the SQ flight at the transit desk, they will be able to arrange for the transfer of your bags. No need to clear immigration.
Yes, SQ goes above and beyond on this score. Very few carriers offer this level of service.