Mixup with kakuteishinkoku when moving
Perhaps someone has posted about this before, but maybe a heads up is warranted given increased scrutiny of residents paying taxes.
I moved to another prefecture at the end of January this year and did all my registration changes promptly. Filed my taxes by e-tax as usual by end of February. Got the kokumin kenko hoken slips from my new city in June and thought 'oh wow the basic payment is a lot more here' but just payed it anyway. You see, I have PR and I'm basically in training, been starting a new career with modest self-employment income at the moment, so usually I would be at the lowest level of residence and health insurance payments.
Anyway, this week i received letters from both my old and new city asking for my income from last year to calculate resident tax and insurance, saying i hadn't submitted a tax return. That led to calling both shiyakusho and getting into kind of annoying conversations where they basically said i must have messed up and not properly filed even though i was 100% certain i had, as i received a tax rebate from the NTA. Finally my old city agreed to look into it and got a call back today.
Basically, your tax return goes to the NTA office in the area you were living on the 1st of the year, and they're supposed to share the info with your old city, who then shares with your new city. But in this case, the NTA office in my old area forwarded the info to my new area without sharing, so neither of the city offices got it. Now i hope this doesn't get into my record somehow as being late in filing or paying taxes!
TL;DR Be aware that there may be mixups when you file taxes in a year in which you moved. If you get notices from your old or new municipalities saying you haven't filed a tax return, don't sit on it and look into it right away!