> My first thought was to work remotely and use the 90 days permitted by the tourist visa. Yet working in Japan on this visa is a gray zone at best and a practice I would stay away from. In fact, the US Embassy in Japan strictly advises against this:
> Persons found working illegally are subject to arrest and deportation.
> Persons believed to be entering Japan without a working visa but who intend to work here can be denied entry into Japan. This means that you will not exit the airport and will be required to return directly to the U.S.
Because you are working in a country, consuming its services, but not paying the local income tax. A work permit either officially ops you out of this or allows you to properly file/pay taxes.
And fyi to Americans reading this: you still owe taxes to the IRS for work done overseas. There are all sorts of deductions and such, but only if you actually file. Not filing in either country could see you owe a huge amount to both, even if that means paying more than 100% tax. Don't risk it.
A lot of countries have laws against working remotely without a visa, although apart from the US few actively enforce them.
Otherwise, opening a work laptop and answering some work emails for your foreign employer would be risky.
This has nothing to do with you working for your own foreign employer while on vacation.