Originally Posted by
Pickles
Be careful there, this is not guaranteed. I've been in flights from the US where we had to re-clear security, and flights were we didn't. The difference between having time for a shower at the lounge and not having time.
No transit security was there for a long while in Narita as a trial, then suddenly it was suspended for a brief while and then came back in both Narita and Haneda. There is a caveat which is if you get a bus gate, then transit security will be the name of the game.