Finding deceased person's NI number

I contacted HMRC to attempt to find out the NI number of my late mother in August however I haven't received a response. I sent the letter with all of the information that the call centre agent told me to send. How long should I expect to wait to hear from them?

Hi Andrea,
The Team that will be able to help you are currently dealing with queries received in February 2024 so, unfortunately, there will be a delay before you receive a reply.  
Sorry for any inconvenience.
Thank you.

Hi Andrea Who did you contact? I am an executor of a will and need a deceased's NI. The person died over 10 years ago. I seem to be going round in circles and getting no-where trying to find a contact number or email to ask for help. Do you have any idea where I can start?

I contacted the NI helpline and they advised me to send a letter with all of the deceased person's information in - full name, date of birth, date of death, address. I also enclosed a copy of the death certificate and my own ID. I haven't heard anything back yet but as you can see above there seems to be quite a backlog. Hope you get sorted soon!

I am trying to find my deceased father NI number, whom passed away in 2008. As I require it for company that owes him outstanding payments . If anyone can point me in the right direction whom to get the NI number from

Hi
Please see the previous post on this thread, the details for contact are National Insurance: general enquiries

I can not get an answer when phoning the N.I. helpline. Twice I've tried and I gave up after 25 minutes. I am trying to get my late father's N.I. number. In the past I tried to fill a form in but the questions were relating to myself. Is there another form relating to deceased relatives

I am trying to find my deceased brother's NI number. This thread was very useful, I did some digging, the address I have sent my request to is PT Operations North East England, HM Revenue & Customs, BX9 1AN, United Kingdom. Now I guess I wait 8 months for a reply.

Hi Irene Caird,
Sorry for the problems in trying to contact us by phone.
The quickest way would be to call our National Insurance Helpline but you can write to us to ask for the details that you require.
If you could give us as much details about your late father as possible (full name, date of birth, date of death, last address) we’ll be able to try to trace his National Insurance Number.
Our postal address is HM Revenue & Customs, PT Operations North East England, BX9 1AN.
Thank you.

My father died in 2018, i only found his grave recently when visiting my grandparents graves. This was a shock. We have tried to ask family but will not provide us with nothing. As far as we know my fathers sister had taken control of his pension, but we have no idea how much he had before or after death , was she entitled to what would have been in her bank account from my fathers pension. Would this be something i need to talk to NI helpline with. Although people appear to be on a long waiting list for there fathers NI number, it looks like i will have to do the same and write as it seems calling the help line gets one no where.