Originally Posted by
marcelduchamp
My journey doesn't begin with UA in the USA but the majority of my flights are issued by UA.
It doesn’t matter who issued the tickets; what matters is the policy for the airline where you’re first checking in. This is a question for the SQ forum.
There is no functional difference between getting your bags checked through on two tickets or three tickets. The steps are the same; the agent will just have to repeat them.