Changing surname as a Japanese citizen

Hello! I am a Japanese citizen but I did not grow up in Japan. Therefore, my Japanese is not perfect and I am unaware of many procedural protocols.

I would like to change my surname to my mother's surname (Japanese) rather than keep my father's due to family issues and identity. I use this new name in a casual sense already, and use my real name as more of an 'official' name for bills and forms.

How can I, and how difficult is it to change my surname under these circumstances in Japan and is it possible to do this from overseas?

Thank you so much for your responses <3

your explanation is uncertain.
your mother is a Japanese and your father is not a Japanese.
you are currently residing in a foreign country.
if so, generally speaking, your real surname in Japan is your mother's one.
the exception is the case when your mother changed her surname from Japanese name to a foreign one.

In any case, if you're in Japan, you can start by asking at your local koseki-ka which is usually a part of your local kuyakusho. If you're overseas, perhaps you can start by asking your local Japanese embassy or consulate.

And I'm pretty sure they'd be asking you what you mean by "mother's surname". Are you saying that your mother and father have different official surnames? Perhaps your father is non-Japanese, then, although you're not. Or perhaps you meant "mother's maiden name". Anyway, good luck to you.

Thank you for your responses so far. My father is non-Japanese and my mother changed her surname to his after marriage. Therefore mu Koseki Tohon is registered with my father's surname. I wish to change my surname to my mother's maiden name.

hire a lawyer who knows Japanese law. he/she will explain you how easy or how difficult.
you need to show the reasons to family court in Japan. probably, "I want to" will not be accepted.

Yes, a family court / Katei Saibansho. As long as I google Ž‚̕ύX, its site is hit and it seems to be explaining what you want to know, it was in Japanese though.

Oh sorry I made a mistake, it was a site of Saiko Saibansho which was saying that you need a permission of Katei Saibansho. A Katei Saibansho is involved in anyway.

Thank you for the clarification. Then, another common option is to be adopted by your mother's parents.

Since your mother changed her surname to your dadfs and you were born to her, changing to her maiden name means for you adopting a completely new name.
Unless she get divorced and she regains her maiden name, and move back with you to Japan or something I donft think that is possible gas a consequence of change in marital/family statush (except for sonething like Zico-san suggested in her last post). Also the rule is one surname per one gkoseki,h so it might be difficult under the current condition.

For gchanging your surname because you wish to (without family/status-related reason),h you have to have a pressing reason, which you need to present to family court. For that, at least you would need to be living in Japan and something like gdifficult to get by with this non-Japanese nameh or some such background needs to be there. Simply wishing to have it changed for identity reason would not convince the court, as far as I know.

A page about Ž‚̕ύX‹–‰Â on 'COURTS IN JAPAN' site says, those who don't reside in Japan can apply the change, if I have read correctly. But yes, I, too think doing it living in Japan is practical and you need a reason which is not like 'I want to change'.

Yes, I have further reasoning to do so, which are slightly unusual and personal circumstances. However, the name attached to me highly affects employment prospects due to associations. I'm sorry that I'm being so vague!

All of your comments have been especially helpful so far - I have contacted an attorney in Japan that I have used previously, and the website mentioned is also very helpful to read.