Pension
Japan pension refund (脱退一時金): who qualifies, how much and how to claim
Japan pension refund (脱退一時金) for foreigners: claim within 2 years of leaving, up to 60 months count. How to apply and get the 20.42% tax back.
Pension
The national pension (国民年金), employee pension (厚生年金) and the lump-sum withdrawal payment (脱退一時金) when you leave Japan.