The U1 application form CA3916 can be found in the following link - Get a statement of your National Insurance contributions (CA3916)
You can submit your completed application online, or you can print it and post it to HMRC.
Please see the ‘How to Apply’ section.
If you have already completed the application form, and you have not received a U1 certificate, I can confirm the following timescales for your application are –
Postal applications – 30 weeks – applications received on 30/09/2022 are currently being processed
Online applications – 3 weeks – applications received on 11/04/2023 are currently being processed
I am sorry to hear that you have been unable to speak to an advisor, our lines are extremely busy at present.
If you have submitted/posted your application, and you sent it before the above timescales, please contact us on +44 19 1203 7010, and we can check if we have received your application. Lines are open from 8am to 6pm Monday to Friday, it may be easier to get through to an advisor when the lines open at 8am.