How much do I have to reveal to new employers regarding pension.

[Self]

I was wondering if it would be an option to tell the employer that you need to do a kakutei shinkoku and just tell them to skip the nenmatsu chosei.

Sure, that is an option. There might be a whole load of reasons why one might have to do a Kakutei Shinkoku.

The Employer still needs the Basic Pension Number for paying the pension contributions next year.

I wonder if Self has Residents' Taxes for 2023, and whether he is paying those by himself, or through his new employer?
The employer will see the 2024 Income when they receive, or have to inform their Insurer for, the Health Insurance Bill in May 2025 and the Residents' Tax Bill in June 2025.

I pay residents' tax on my own, but my previous employer used to pay that for me. My current one does not.

[Tkydon]

Thank you. They told me earlier I would have to file my tax by myself. Just wondering if I have to provide them with paperwork regarding the unemployment benefits I received.

Yeah, You have already missed the deadline for them to do the Nenmatsu Chousei this year.

I pay residents' tax on my own, but my previous employer used to pay that for me. My current one does not.

If you tell your current employer they will be able to pay it directly from payroll, or you can keep paying it yourself.

[Self]

Thank you.

I just gave them a copy of the paper they asked for. It didn't have as much info on it as I expected, so that's good.