Originally Posted by
CPH-Flyer
Normally yes, but you would need your arriving boarding pass.
A few caveats, it has to be the same airport (NRT/NRT or HND/HND), international to international, and same day by the lounge opening and closing flow. If you can be more specific on the route you are considering, a more specific answer is possible.
Thanks,
CPH-Flyer. That's all I needed to know. It would be a same day, same-airport (either HND or NRT, haven't decided on the routing yet), international-international connection (U.S.-TYO-SEL).
-FlyerBeek