Changing my surname in Japan after 4 years of marriage — questions about Family Court and city hall

Hi everyone,

I’m Japanese and married to a foreign husband. I didn’t change my last name when we got married, but now, 4 years later, we’re expecting a baby in December. I want us all to have the same last name, so I’m planning to change my surname.

I have a couple of questions:

1. How long does it usually take to change a surname through Family Court in Japan? I understand that since it’s been more than 6 months after marriage, I’ll need court permission.

2. When my sister changed her surname to her foreign husband’s, the city hall included his middle name in the official record. So her surname became middle name + last name, while her husband’s is just last name. That means their surnames technically don’t match. I feel like it would be pointless (意味ない) if that happened to me too. Is it possible to register only my husband’s last name without the middle name?

Thanks in advance for any advice or experiences you can share!