AFAICT/R, JP Post banking used to be really barebones, even for late 2010s Japan. No credit cards/debit cards, not a lot of financial products, etc. In recent years it seems like they have added a credit card and a debit card and online banking as well.

On the flipside, they are one of the most ubiquitous ATMs in Japan and your local post office will double as a branch for JP Post Bank (which are everywhere).

Oh and it's nation wide too! Which is kind of important for a country where some banks restrict activities and branches to their direct locality.

Man. I wish patio11 would talk about Japanese banking more because to most American audiences that system is also just, completely something else.