The LAX flyaway runs 48 buses daily, every 30 minutes (or less during rush hour) between LAX to Union Station.
LAX Flyaway shuttle bus
Check out the website
LAX Flyaway
Information booth will answer all your question. Veru helpful
They have a bus that I think is called Skybus (check the LAX website) that takes you nonstop to the station. You can buy tickets online.
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