Codeshare agreements let airlines sell seats on each other's flights under their own flight number, which is why you might book with one airline but see a different carrier's name and aircraft when you check in. It's a standard practice, especially common on international routes operated through global alliances.
Baggage allowances, seat selection rules, and check-in policies can follow the operating airline's rules rather than the airline you booked with, which occasionally surprises travelers expecting their usual airline's benefits. Always check the fare rules for which airline's policy actually applies to your specific booking.
Loyalty program earning is another area to double-check: miles earned on a codeshare flight usually depend on the fare class booked and the specific partnership terms between the two airlines, not automatically matching what you'd earn on that airline's own operated flights.
