US tax and question about address

Hello, I had a couple of questions I was hoping a few of you might be able to answer. I will be working in Japan again this spring (I worked there for 2 years previously), and am in the process of obtaining my visa.

My first question is for US citizens working in Japan. My previous employer in Japan had me apply for and get a 6166 form (Certification of U.S. Tax Residency). I will check with my new employer, but do I need to file for this form again?

I am also planning to live together with my boyfriend (Japanese) and commute to work from there. I visited him last fall (as a temporary visitor) and wrote down his name and address of the disembarkation card, and since I plan to live with him this time I will do so again. My question is, do I need any kind of documentation to say that I plan to live with him/ does immigration need anything like that? My impression is that it's not necessary, but I'm not sure.

Thank you for your time.

peachtea said:

Hello, I had a couple of questions I was hoping a few of you might be able to answer. I will be working in Japan again this spring (I worked there for 2 years previously), and am in the process of obtaining my visa.

My first question is for US citizens working in Japan. My previous employer in Japan had me apply for and get a 6166 form (Certification of U.S. Tax Residency). I will check with my new employer, but do I need to file for this form again?

I am also planning to live together with my boyfriend
...
Thank you for your time.

Click to expand...

Certification of U.S. Residency for Tax Treaty Purposes

I'm puzzling over why someone who would be (or is) working in Japan would want or need to claim US tax residency.

(Total speculation, but your previous employer might have used this to avoid taking taxes/pension/health contributions out of your salary--effectively making your take-home pay higher.)