change your address after you claim for pension refund
What to do if you moved to a new place after you claimed for your pension refund? You are supposed to receive a notice of remmitance of Lumpsum-Withdrawal Payment from Japan Pension Service when you received your pension refund. With that letter (a notice of remmitance of Lumpsum-Withdrawal Payment), you can claim for your tax refund which was deducted from your pension refund amount.
The tax is 20% of the total amount of the pension refund. It is not a little money if it is 20%. Isn'it?
If you moved to a new place and if there is no way that Japan Pension Service can reach you, then you will miss receiving a notice of remmitance of Lumpsum-Withdrawal Payment and you can't claim for your tax back.
However, you do not have to worry because there is a way. You just have to wirite a letter to Japan Pension Service with required information and let them notify that your address is going to be changed!