"Postal Code / Digital Address for Biz" can be used after registering your Yu ID and registering a business account on the website.
For frequently asked questions or inquiries about "Postal Code / Digital Address for Biz," please refer to the "Q&A for Corporate Customers."
<Postal code / Digital Address for Biz(JPN ver only) >
https://guide-biz.da.pf.japanpost.jp
<Q&A for Corporate Customers(JPN ver only) >
https://www.post.japanpost.jp/question/business/index.html